Chinertown
Chinese Carbon MTB => 29er => Topic started by: sclyde2 on April 10, 2018, 06:00:47 AM
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Build just completed today.
I was looking for a dedicated XC race bike. I felt my old FS 26er (a 2011 Titus X carbon, ~10kg) just doesn't cut the mustard anymore. I tried my 29er hardtail (FM057) in a few events last year, and preferred its handling (over the 26er), but found the ride a bit too rough, so I began a search for something similar to my FM057, but with rear suspension.
For a while there, I was tempted by the M06, but then came across that thread on the French light bikes forum (by Tom in here).
After changing focus to the FM058, I was initially looking for the FM058SL, but the long lead time scared me off. I ended up ordering the "normal" FM058 from Hong fu. Even though they said it was in stock, I ended up waiting about 5 or 6 weeks before they shipped it. I received the frame a few weeks ago.
I also built up a new set of wheels.
I have moved quite a few parts off my other bikes.
This is the current build:
(*old parts scavenged off my other bikes)
Frame/shock
FM-058 17.5" UD gloss (incl all bolts) - 1960g
Manitou mcleod shock 165x38 - 252g as shipped (with bush), 242g with bush removed
RWC needle bearing kits - 21.85 + 22.2 - shock weight with hardware installed - 276g
Actual total frame + shock weight = 2.24kg
Wheels
*240s 15x100 SP CL - 122g
*240s 12x142 SP CL xd freehub 54t ratchet - 217g
28 X 302mm black cx-ray SP - 139g
28 X 302mm black super cx-ray SP - 119g
28 X 2.0/12mm brass nipples - 27g
28 X 1.8/12mm brass nipples - 27g
Xmcarbonspeed 30mm (ext) T800 assymetric rims - 303g/307g
Actual total wheel weight - 582 +682 = 1264g
With stans 27mm yellow tape - 591/691. Tape was 9g/rim
*Racing Ralph 2.35 speed f - 580g
Racing Ralph 2.25 speed snakeskin addix speed r - 660g
Tubes - schwalbe SV 19A - 148/149g
Drivetrain
*M9000 xtr pedals - 308g
*M980 xtr cranks 170mm with all bolts (all except ring and BB) = 540g
*32t RaceFace narrow wide chainring 35g
Hope screw together pf41 BB - 116g
Xx1 11 speed chain - not weighed
*Xx1 11 speed cassette - 274g
*Xx1 11 speed shifter no bracket = 98g incl bolt
*Xx1 11 speed der - 245g
Brakes
*Xtr M9000 front incl all bolts - 198g (caliper bolts are about 6g)
*Xtr M9000 rear - not weighed
*Rt99 rotors 160/160 - 101g/101g
*Front CL lockring - not weighed
*Rear CL lockring - 8g
Cockpit
*3T carbon post doric ltd 400mm cut to 380mm + old selle italia slr xc saddle = 361g.
*Cheap QR seat clamp - 42g.
70mm uno 7 stem - 94g (with steel bolts). took about 9g off this by subbing in some ti bolts
*easton Ec70xc 685mm riser + esi chunky grips + end caps + SRAM shifter bracket = 222g
Other
Rear axle (supplied with frame) - 87g
*Fox 2013 f32 100 ctd factory with remote, cable, axle, starnut & crownrace - 1710g
Cane creek 110 is52 lower, bearing only - 28g
Cane creek carbon 40 is42 upper - 30g
*k-edge Garmin mount - 22g
*Garmin cadence sensor - 11g
*King ti bottle cage 30g + Ti bolts 3g
framewrap on chainstay - about 30g
stuff not weighed: cables, rear brake, front CL lockring, chain, headset spacers/topcap/bolt
Total bike weight: 10.29kg. That's ready to race, bar a water bottle, number plate and garmin.
Future changes
9g tune seatclamp ordered. Will save 33g when it replaces the QR clamp
setback seatpost. Not sure which model yet. Need about 20mm setback, with good rail support. Like the clamp on trhe syntace p6, but it might not have enough setback. I also like the clamp on my old easton ec90 zero post, so maybe the setback version could be good. i saw a decent looking one on the xmcarbonspeed website too.
*SLR kit carbonio saddle - will put this on when i get the appropriate seatpost
go tubeless - once i have had a few rides and checked the spoke tensions in the wheels.
Pretty happy with how everything went together. Haven't quite got the saddle position correct, as it is still about 10-15mm too far forward, so am looking at setback seatposts.
The main issue i have with it is internal cable rattle. Anyone got any ideas how to stop this? I have tried pulling the cables tight, and attempting to hold them there (at the exits) with zipties, but i think they slip.
Other than a few test rides around the streets around my house, it hasn't yet been ridden. Rear shock seems amazingly plush, and i have it at 150psi (for my current ~77kg) with very little sag, but it is still plush and seemingly bob-free. Did all the setup with the platform wide open though - will probably use one of the harder settings when i race it.
First proper ride is this weekend. I think it'll be in a race situation, at one of the local club's events on sunday.
it is looking very promising. I hope i like the "modern" geometry, which is one step beyond my hardtail (FM057), but whole different world to my FS 26er.
I will post some ride impressions here later.
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more photos
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Awesome build bro. Really nice.
About the rattle: push one or two kitchen sponges into your frame where the cables make noise. Before doing so don't forget to attach a cord to the sponges. So you can easy pull them back. Light weight solution.
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Thanks for the suggestion, I'll look into it.
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Super awesome build, super light too. I might pick up an FM058 frame this month...
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Nice build! Good luck with it this weekend. Give us a report about what you think of the ride.
For what it's worth: I have a M06 and there is no issue with the rear triangle support hitting the seat tube. With the shock fully bottomed out it's not even remotely close to hitting. I have read the thread from the French forum too and have no idea what was happening there. Maybe a design change was made before i received mine??? I purchased my frame last summer so new frames definitely will not have a clearance issue.
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That build is awesome! Thanks for sharing.
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Super awesome build, super light too. I might pick up an FM058 frame this month...
Please post it when you do.
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Super awesome build, super light too. I might pick up an FM058 frame this month...
Please post it when you do.
Will do....
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Nice build,
from 26" to 29" straight to a race without a few pre rides ? wish you well ;)
The main issue i have with it is internal cable rattle. Anyone got any ideas how to stop this? I have tried pulling the cables tight, and attempting to hold them there (at the exits) with zipties, but i think they slip.
here is something efficient you can do : http://www.light-bikes.fr/phpBB/viewtopic.php?f=45&t=928&start=50#p26274
(http://images.empreintesduweb.com/originale/1467148604.jpg) (http://images.empreintesduweb.com/1467148604.jpg.html)
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here is something efficient you can do : http://www.light-bikes.fr/phpBB/viewtopic.php?f=45&t=928&start=50#p26274
That's a really cool trick ... for new builds or when you're replacing your cables. I'll do this on a new build for sure.
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Nice build! Good luck with it this weekend. Give us a report about what you think of the ride.
For what it's worth: I have a M06 and there is no issue with the rear triangle support hitting the seat tube. With the shock fully bottomed out it's not even remotely close to hitting. I have read the thread from the French forum too and have no idea what was happening there. Maybe a design change was made before i received mine??? I purchased my frame last summer so new frames definitely will not have a clearance issue.
I didn't have any doubts that they fixed that issue on the M06. I just liked the idea of the FM058, with all the force centred on the bottom bracket, and Tom's build was quite inspiring. I did read something about the M06 having a bit of play in the rear end, which worried me. Having said that, I am little worried about some play developing on my FM058, as the hole in rocker where the top shock bolt passes through might enlarge, causing some play. Gonna ask Hong fu if I can get some spare rocker links.
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Nice build,
from 26" to 29" straight to a race without a few pre rides ? wish you well ;)
here is something efficient you can do :
It probably isn't ideal that I don't do a proper ride before I race it, but this weekend's club race is the last race i can do before I do a longer more important event (about 3hrs) next month, and need some race experience on my new bike before I do that.
I am not so worried about acclimatisation to the new bike, as i have thoroughly used all the bike's contact points (saddle, pedals, bars grips), drivetrain, brakes and even the fork. Yeah, going from an old school geo 26er to a modern geo 29er will be the biggest change, but my 29er hardtail has similar geo to the new bike, and I adapted quite well to that when I raced it last year - though I haven't ever ridden a xc bike with a reach this long, or a stem that short. I am probably more worried about something being not quite right with my build, such as a slipping handlebar or something like that.
I will do a 20-30min pre ride of the course prior to the race though, so hopefully any possible build issues crop up then.
As for the zip tie trick, my friend mentioned that his bike shop did that on his bike. I think they attached the zip ties like that, fed the cable in, then twisted/spun the cable, so that the zip ties spiralled inside the frame and suspended the cable in the middle of the frame tube. I was hoping for something a little easier (i.e. externally pull cables tight), but I think I'll have to some something internally to fix it. I have read of other suggestions, where they put something soft around the cables, like some kind of rubber or Velcro.
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I did the zip tie trick to stop the internal cable rattle. I won't know for sure until I take it for a proper ride, but it appears to have worked.
It certainly would've been a lot easier to do if I did it before I originally routed the cables, connected up the brake hose or installed the bottom bracket. I also wasn't equipped to remove the bottom bracket, so access was pretty tough. It took a while, but I managed to get zip ties on the gear cable along the full length of the downtube. I didn't quite get zip ties along the (downtube) length of the brake hose, but got most of it (mainly the bottom half, only a couple up at the head tube end). Hopefully I have done enough.
I have managed to find some time to go for a ride tomorrow at a local trail - a xc-ish loop, with a few rougher bits, a few challenging features.
So official new bike day is tomorrow. Feels like Xmas Eve again.
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... I have read of other suggestions, where they put something soft around the cables, like some kind of rubber or Velcro.
Capgo provides a foam shell to wrap the hoses: http://capgo.de/en/capgo-ol--noise-protection--2m_1111.html ( and quite a few other good products ).
r2-bikes sells them too: https://r2-bike.com/CAPGO-OL-Noise-Protection-for-Brakehose-Braking-Outer-Shell-2m
However I don't see clearly how to put either the foam shell or zip ties inside the frames.
But will certainly try next time too.
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i took the bike for its first ride. did 2 laps of a local loop, about an hour total.
the anti-cable-rattle-solution i attempted was not 100% effective. occasionally i could hear a faint rattle, but it was rare. for the moment, i will leave it as is, as it isn't very bad at all, and the trails i rode on were particularly rough and rocky so i probably won't hear it in a race. (I might look into that capgo stuff though)
anyway, the minor cable rattle is completely utterly outweighed by the way the bike rode. it blew me away. even though i've had a few ellsworths, a few titus bikes, it surprised me just how great this bike is. it isn't my first 29er but i suppose it is my first 29er full suspension, so maybe that partly explains it. it was just effortless at ploughing through the rough stuff, maintaining momentum. when looking at sizing (i'm usually between small and medium), i was a little concerned that it might be a touch too long for me, that i might struggle to get enough weight onto the front tyre for cornering, but I found no such compromised cornering. given the wheelbase on this thing (longer than my other bikes), i was very surprised how well it pivoted around corners - there's gotta be something in that short 435mm chainstay length.
everything felt flatter - the techy climbs were easy, with no signs of reaching the traction limits, and the down steppy techy droppy bits seemed so easy. the shorter stem, slacker headangle (compared to my old FS 26ers 90mm and 71 degrees) and bigger wheels certainly eliminated those front-tippy feelings that i had through certain downhill obstacle sections on my old bike. i certainly feel more "in" the bike, rather than "on" it, so reckon i will have a bit more confidence to push it a bit harder through the fast and techy stuff.
there was no noticeable bobbing under power. the high main pivot should give it a bit of anti-squat, and that's how it seems to ride - though i havent yet done any smooth long climbs to really test that out. i ran the rear shock with the platform wide open while i tinkered with the air pressures. started the ride at 140psi in the rear shock, dropped it to 130, then hit a decent sized jump, and launched it - even though i didn't feel it, i measured the full 38mm of travel being used on the rear shock, so bumped it up to 135 and will leave it there for the next few rides/races. i then put in on the 2nd platform setting (of 4) and will leave it there for the race on sunday. i usually tend to notice bobbing in the fork more when stomping anyway, and have a remote lockout for that. having said that, i will probably get the new rockshox twistloc when it comes out - a 10mm cable pull on my fork and rear shock will suit me well. i left the fork at 85psi, and managed to use about 95mm travel.
i did not notice the slightly forward position of the saddle (about 10-15mm forward of where i usually have it). given how well it went, i am a bit hesitant to change anything, but i will still get a setback post, mainly so i can put the middle of the saddle rails on the clamp, so i can use my carbon railled saddle. one of my calves is prone to tensing up and cramping, so i recently started experimenting with slightly further rearward cleat position, which necessitates a slightly forward saddle position - so maybe my new "norm" saddle position will be close to where it is currently on my new bike. we'll see how this experiment goes.
other than previously mentioned changes (lighter seatpost clamp, sealant instead of tubes), i can't see myself changing anything. i have been looking at newer 51mm offset forks, but my old fork, which got serviced recently, went so well, i see no real need to upgrade it (yet). i was considering converting it to tubeless before sunday's event, but i think i'll be patient and stick with tubes until after i finish the event.
i am pretty sure this new bike will make me faster. i won't know for sure until i have my next race at my club, at the usual race track, against the usual competitors. that isn't until next month though. i am still very much looking forward to this sunday's club event (at another track i havent ridden in years).
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The new bike's maiden event on Sunday went very well. It was on a course that I hadn't ridden for over 6 years. I tried to get in some practice before the start, but ran out of time - and got a bit lost trying to shortcut back to the startline, and nearly missed the start!
The track upgrades since I last rode it were phenomenal. It is one twisty track, through lush rain forest, with hardly anywhere to easily overtake, and not many opportunities to grab a sip from the water bottle. It sure was gonna be tough to ride fast with so little track familiarity. As expected, on the first few laps, I stuggled to keep with the front runners through the super twisty bits, getting gapped - not because of my bike, but because I didn't know what was around the next corner. I was having major issues knowing when to push harder and when not to. For the first half an hour I was able to close the gaps on the straighter pedally bits, but was struggling so much with flow, that it was getting tiring and had to back off a bit in the middle part of the race, and find my rhythm. The last 15 minutes were a different story - in the 4th (last) lap I felt a lot more comfortable, and was linking the corners together much better. Started catching others quite quickly, but ran out of track. Ended up about 2 minutes behind the winner (~80minute event).
One thing I learnt is that I could stomp through the rougher short climbs in a much higher gear, and maintain momentum at a much higher speed than I am used to on my other bikes, all the while expending a surprisingly low amount of energy. This was somewhat of a revelation, which I will explore further in future events. I found that this technique was a massive gap closer (or opener).
I was surprised how well the bike cornered with the long reach/short stem combo. As I rode it, I was initially thinking that there was no downside. But I then i noticed that I was a bit slow with the uphill switchbacks - not sure if I can overcome this will more practice / improved technique.
Everywhere else the bike felt like a zero compromise ride. Super plush but no noticeable bob, felt perfectly sized, and went up the really steep stuff so well that I would've preferred more super techy pinch climbs, as I felt I had an advantage on those around me when the track turned skywards.
All in all, very happy with the bike.
No events for 3 weeks. Plan to wash it, check the spoke tensions, and convert it to tubeless. The seat post clamp is still on the way. I won't be changing anything else for a while - the air pressures (tyres and suspension) are gonna be left exactly as is.
After I do the longer event, I am gonna revisit last weekend's track for the next club event. It was such a fun track.
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...Ended up about 2 minutes behind the winner (~80minute event)...
Congrats!
Especially if they knew the course, and you didn't.
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I did read something about the M06 having a bit of play in the rear end, which worried me. Having said that, I am little worried about some play developing on my FM058, as the hole in rocker where the top shock bolt passes through might enlarge, causing some play. Gonna ask Hong fu if I can get some spare rocker links.
The play you are referring to is not from wear. It's that way from the build. I have that "play" in my bike (M06) same as what you described, the top shock mounting hole on the rocker is just a little too big for the bolt. You can barely notice it. Only when you're off the bike and pick it up by hand you can hear a little click. I would not be concerned about yours getting worse. I've been riding mine for about a year and it has not gotten worse.
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I converted it to tubeless. Now 10.17kg. ~120g lighter than before.
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Build looks great sclyde2. I just bought the FM078. What tune does your rear shock have? I plan to use a Float RP2 that has M rebound, L velocity and 350 boost valve tune (I don't understand this all to well). Any opinion? thx
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Build looks great sclyde2. I just bought the FM078. What tune does your rear shock have? I plan to use a Float RP2 that has M rebound, L velocity and 350 boost valve tune (I don't understand this all to well). Any opinion? thx
I just googled the FM078. It appears to be a hardtail. Given that you have some questions about a rear shock, did you mean FM058?
I have a manitou McLeod shock. I believe that there is only one factory tune for each size McLeod shock.
As for fox shocks, I do have some experience with those. I assume the "velocity" that you refer to is the compression damping tune. Fox's L compression damping is suited more to frames with lower leverage ratios (around 2:1). The FM058's leverage ratio is not low, around 2.6 - if I were getting a fox shock for the FM058, I'd be looking at the M compression tune shocks.
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078 is the boost version of the 058. (I will be extremely disappointed if a hardtail arrives!)
http://www.hongfu-bikes.com/html_Products/Mountain_Frame/650B_29ER_Plus_Frame/2017/0322/481.html
Does the leverage ratio on your 058 seam pretty constant? No "platform"? I was thinking if the RP2's tune was not compatible I'd try x-fusions "micro-lite". I see no tune options for this shock (micro-lite).
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078 is the boost version of the 058. (I will be extremely disappointed if a hardtail arrives!)
http://www.hongfu-bikes.com/html_Products/Mountain_Frame/650B_29ER_Plus_Frame/2017/0322/481.html
Does the leverage ratio on your 058 seam pretty constant? No "platform"? I was thinking if the RP2's tune was not compatible I'd try x-fusions "micro-lite". I see no tune options for this shock (micro-lite).
It sure is a bit confusing when they recycle the model designations.
As for leverage ratio curve, I don't know - I am no expert on that stuff. But the standard air can (rather than high volume) seems to suit it. As for platform, I notice no bobbing or wallow, but I don't think my shock is broken in yet (I read somewhere that it takes 10 or 20 hours). Looking at the bike, with its main pivot above the chain (with a 32T chainring), has gotta give it some anti squat.
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The 11g seatpost clamp arrived. Bike now at 10.13kg. That's very close to my 26er (10.11). That's where it'll stay for a while. Gonna put off the seatpost purchase, as I am not yet convinced that I need a setback post. The carbon railled saddle can stay on the old bike for a while longer.
I got a little prep to do for a longer event (~3-3.5hrs) in 9 days' time. I got some of those kcnc clamps so I can run a bottle cage on the seatpost - going to try a no-stop strategy with no hydration backpack
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The 11g seatpost clamp arrived. Bike now at 10.13kg. That's very close to my 26er (10.11). That's where it'll stay for a while. Gonna put off the seatpost purchase, as I am not yet convinced that I need a setback post. The carbon railled saddle can stay on the old bike for a while longer.
I got a little prep to do for a longer event (~3-3.5hrs) in 9 days' time. I got some of those kcnc clamps so I can run a bottle cage on the seatpost - going to try a no-stop strategy with no hydration backpack
Is it going to be a flat terrain ? Carrying the extra weight uphill might be a bigger challenge when comparing to a quick refill stop or bottle exchange.
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Is it going to be a flat terrain ? Carrying the extra weight uphill might be a bigger challenge when comparing to a quick refill stop or bottle exchange.
Yeah, thought about that.
I take all my carbs in liquid form (gels seem to usually be a cramp risk), so there's no "quick refill" for me.
Have done enough 100km+ races (not this weekend's) to know how long it takes me to stop. I.e. gloves off, half fill the bottle with water, pull out the bag of powder (sustained energy or perpetum), carefully tear it and get it into the bottle, lid back on, shake it, fill the rest, gloves back on and get going again. Can't rush it or the powder goes everywhere. If it is one of those longer events, then there's a hydration pack to fill too (in the 100k+ events). Always takes longer than expected.
Not flat terrain - after about 10 mins of flatness, the next half hour is spent going mainly up. Some ~15% stints. Yeah, carrying an extra 700-800g up that is felt. But I still reckon the additional energy (and time) required to carry it until the halfway feed station is not as bad as the alternative (stopping and mucking around with powder and a bottle, which is also quite disruptive).
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...Have done enough 100km+ races (not this weekend's) to know how long it takes me to stop...
I'm just starting to do some, and there are so much things to learn about yourself, manage your effort, it is overwhelming.
I tried to find some resources on the web, to help but didn't find them really.
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the longer event yesterday went well. even though i am about the same weight as last year (still over 3kg above where i get to later in the year), about the same fitness, and the course was a bit tougher (exact same route, but the long last downhill was particularly eroded, and the dirt road at the end seemed to be more corrugated), i managed to slice more than 8 mins off last year (~0.8km/h faster). yeah, i did break a chain last year which accounted for nearly 4 mins of that though. was one place off getting into the top 5% of finishers, which is pretty good for me.
strava tells me i was a bit faster just about everywhere. climbs, most downhills. last year on my hardtail, i was a tiny bit faster on the flat road bits (including two sections of sealed road) and on the last downhill (which, as mentioned above, was quite treacherous this year). the FM-058 totally destroyed the hardtail when it came to the rough stuff in the middle of the event. especially a section with relentless rock step ups. i quickly realised that this bike is amazing at going up that stuff. when encountering slower traffic through these step ups, i could make my own lines around them and get up the biggest steps, probably the biggest i have ever done. all losing minimal momentum. i certainly could easily get used to this.
in other news, the night before the event, i noticed that there was some knocking in the rear end, when lifting and dropping the bike. i realised that a few of the pivot bolts had come slightly loose. i'd only ridden the bike 3 times before that. i probably should've checked them on delivery. i suppose that is something to look out for when buying these chinese frames. gonna keep a close eye on those, maybe looking into putting some locktite on them.
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How is the margin between the frame and chainring. I have little problems here with same frame. I can not use any bigger than 32T
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Only when you're off the bike and pick it up by hand you can hear a little click. I would not be concerned about yours getting worse. I've been riding mine for about a year and it has not gotten worse.
That's encouraging to hear, I was concerned with that click for a while and thought it was caused by lack of tension at rear shock binding post.
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How is the margin between the frame and chainring. I have little problems here with same frame. I can not use any bigger than 32T
I don't have the bike in front of me (to measure the gap between the chainring to the frame), but I had plenty enough clearance, such that I have no concern that flex could cause contact. I even put a 34t on, and there was still plenty of clearance.
I saw that you linked your cranks on the other thread. CRC's SRAM stuff is geoblocked for my country, so I am not sure exactly what crank and ring that you are using. I am not that familiar with sram 1x cranks with direct mount rings. I did look up sram cranks and I didn't really find anything that definitive on their chainline anyway. I could not find another image of the 11s direct mount chainrings with "blackbox" written on it like yours, so don't know what chain ring you have.
Overall, I dunno what is going on with your crank-chainring-bottombracket setup, but you are the only one I have heard of that had an issue with chainring clearance on this frame (including all the equivalents from hongfu and other suppliers). AFAIK, these frames all come out of the same mold (for each size), so I can't see how your frame would be different from everyone elses.
It seems to me that your issue is more likely the chainline of your crank/ring. AFAIK, just about every 3x shimano hollowtech mtb crank has a chainline of 50mm for the middle ring position. I would suggest that you grab one of these Shimano cranks (most people I know have an old one of these either on one of their backup bikes, or sitting in a parts bin, and they usually have a 32t) and put it on to check clearance. You might need to remove a spacer or get a different bearing to get the (gxp) 22mm side up to 24mm, so the Shimano axle fits.
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Ok, i will try shimano M8000 and see if it works.
Now i used this:
http://www.chainreactioncycles.com/se/en/sram-pressfit-gxp-alloy-bottom-bracket/rp-prod75586
http://www.chainreactioncycles.com/se/en/sram-x01-11-speed-chainset/rp-prod122747
32T SRAM Chainring. 6mm offset for 11 speed setup. - https://www.sram.com/sram/mountain/products/sram-x-sync-direct-mount-chainrings
Should be 49mm chainline when use this setup.
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Ok, i will try shimano M8000 and see if it works.
Now i used this:
http://www.chainreactioncycles.com/se/en/sram-pressfit-gxp-alloy-bottom-bracket/rp-prod75586
http://www.chainreactioncycles.com/se/en/sram-x01-11-speed-chainset/rp-prod122747
32T SRAM Chainring. 6mm offset for 11 speed setup. - https://www.sram.com/sram/mountain/products/sram-x-sync-direct-mount-chainrings
Should be 49mm chainline when use this setup.
I washed my bike yesterday, and had a closer look at the chainring clearance. It isn't as much as I thought. If the chain line was about 2mm less, it would be close to touching the chain stay. How did you go with the Shimano crank?
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1 year Update:
My bike turned one this week. In total, I'm guessing I've done about 15 events on it - mostly ~70-80 minute xc events at local clubs, about four or five longer events (mostly 3-4hrs) and one 35 minute short track event.
With 2 young kids (2 and 3), I don't have much time for riding. I get my fitness from commuting to work (around 200 of my 240hrs in 2018 were on my fm057 hardtail commuter), go in the above mentioned races, and do minimal other off road riding. I have only ridden the fm058 in the above mentioned events, and less than 10 non race rides (such as reccy missions to pre ride race courses). My long travel 26er has barely been ridden since I built up my fm058 - the old bike geometry feels weird now.
Log of changes since initial build:
April (2018) - Converted to tubeless. Bike lost 108g with that conversion.
April - tune seatpost clamp. About 30g savings
May - got same saddle and seatpost that sissypants has (well, at least back then). The seatpost was a bit heavier than claimed, but saddle was pretty light. The saddle is the comfiest I've ridden. Seatpost and saddle totalled the same weight as the previous setup (within 10g).
August - Removed the zip ties on the internal cables and put in capgo noise protection. It works. Get it.
August - Got a light rear axle. Robert project. 42g (saved 45g)
August - 2.25 thunder burt rear tyre. 575g (85g lighter than old tyre)
October - Got a 2nd hand fork - fox 32 factory SC non boost 46mm offset remote lockout. Used the remote lockout off my old fork (80g including cable). took 230-240g off the bike.
February - Changed front tyre - 2.25 racing Ralph speed grip snakeskin (thicker sidewall than old tyre, 639g, 59g heavier than old tyre)
February - New crank with oval chainring - rotor rex 3.1 with 32t oval chainring. Overall, 10g heavier than old crank/chainring setup.
As pictured, bike now weighs 9.81kg (ready to race, just attach number plate and Garmin and go).
Next changes:
Different coloured decals for fork. thinking red
New front tyre - 2.25 racing ray
32t oval chainring absolute black - a bit lighter and slightly narrower chainline
The bike has been a joy to ride in races, and I have been steadily improving on it. Other than one exception (where I had dehydration issues, that I blame on excessive pre-race coffee), I have had steady improvement in the results I am getting on this bike. Have had a few 3rds, seconds, and finally started getting some wins starting near the end of last year. Before all this, I never got better than 4th in these kind of races. I can now expect to keep up with the front runners, up, down, just about everywhere. Climbing is great, descending is great, and I seem to get a little better at cornering every time i ride it.
For a while there, the only downside of this bike for me was I was struggling a bit on the tighter uphill switchbacks. This is probably because the reach on this bike is longer than I'd normally run, and I have a very short stem on it, making it harder to weight the front tyre in certain situations. Lately though, it seems I am shifting my weight better and getting around them faster, and not losing ground.
I haven't touched the rear shock (think it is still around 135psi) and always run it with the compression setting fully open. I notice no Bob, even when stomping. Must be the high main pivot with the 32t chainring (anti squat has been discussed elsewhere on here).
While I considered that the chainring clearance was pretty good when I initially set it up with a 32t round chainring on my m980 xtr crank (50mm chainline), I ran into problems when I attempted to put an oval chainring on it. I was determined to put a 32t oval chainring on. The chainline for a 32t oval on my xtr crank is 48.5mm and I bought one of those chainrings, and it didn't fit (chainring hit chainstay). After much research I ended up with a rotor 3.1 crank, the one with the 24mm axle so I didn't need to mess with the bottom bracket. The rotor oval ring on that had a chainline of nearly 51mm, so has plenty on clearance. The chainline is not ideal for non boost, and is a bit grindy in the big cog, so I have ordered an absolute black chainring for it, which apparently are quieter and are a mm or two further in. Would've had much more options if I got a boost frame.
The Chinese seat post I am using has barely enough setback, especially when combined with the Chinese saddle I am using (the rails on the saddle don't allow much rearward movement). With the setback in the post, plus with the saddle almost all the way back, and I am barely as far back as where I have been riding my commuter for the last few years. I am ecstatic with comfort of the ~$25 saddle on longer events, so much so that I have 2 spares, and recently put one on my commuter too. There is one downside of the saddle : my shorts get stuck on it when I get behind the saddle. I'll have to work around it.
Soon after I initially put the bike together I noticed a tiny bit of play in the rear end, when picking up the bike by the saddle. It is very very minor, so minor that I cannot be sure where it originates. Others have mentioned these kind of frames have play in the shock bolts. When I initially built the bike, the top shock bolt bottomed out before it got tight, so I put a washer in there. My measurements came up with 21.8 for the top shock mount. Maybe I should've used a 22.2 and spread it a tiny bit. After recently confirming that I could get 22.2 to fit, I ordered another 22.2 RWS needle bearing kit and put it on this week. It seems to have worked, but we'll see if the play comes back after a ride.
This is my first frame with a press fit BB. I was paranoid about creaking, so put one of those (heavy) screw together hope BBs on it. WIthin the first month, I did detect some minor creaking, but did some research, and realised that I was putting to much pressure on the bearings, so I loosened the cranks a bit, and have pretty much forgotten about it (so it is silent).
I do have some concerns about the durability of the frame overall. Maybe I am about paranoid, but I the play in the rear end has got my worried it had weakness in the pivots. I have also had the headset loosen, and noticed that my headset now requires a spacer to avoid bottoming the top headset cap on the frame, suggesting something has moved - either something compressed in the top headset, or the frame's top headset cup has been pushed down.
Despite these concerns, I have no regrets getting this bike. I am continuing to beat previous pbs on Strava segments throughout the local racetracks, and am now beating people I have never before. Not bad for someone in their 40s.
The bike is almost too good at pedaling, which I put down to the high pivot and the inherent anti squat. I am used to very active Horst link bikes, so I would maybe prefer a slightly more active setup. If I was to do it again, I suppose I'd run a bigger 34t chainring (less anti squat), but then I'd probably need boost spacing to get the clearance, and probably a bigger-than-42t rear cog to get the low gear. But I am happy with what I have, with no need to bother with a rear lockout.
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nice bike,
I have the old fm036 the play you refer too in the back end might be what I had this was down to the mounting holes for the shock being slightly larger than needed on the linkage. I eventually cured this by using a new ti nut and bolt, whereby via complete accident the nut was drawn into the linkage recess and wedged there firmly enough to act like the hole was re-bored. Play now cured.!!!
best regards
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Since the last post, i have put a racing ray tyre on the front - only 2 rides in, so far so good. I also purchased an absolute black chainring, which promised a slightly narrow chainline, and a bit less weight - well, it turns out it was lighter, but the chainline was identical to the other rotor chainring, and the oval shape was identical, but slightly different teeth shape (a tiny bit less grindy on the bigger cogs). The chainline on this non-boost bike is probably the worst thing about it. good thing i very rarely use the big cog these days.
The play in the rear end got slightly better with some new hardware for the mcleod shock (back in april), where i got another slightly wider (22.2) RWS bearing kit. but then it got worse again. After noticing that the hardware was looser than expected (i didn't even need to press it, it just went in easily with a finger), I have been doing some research on the mcleod shock, and have discovered a few issues - 1. the hardware can be loose (can be solved by some custom-sized hardware), 2. there can be some knocking internal to the shock (which is easily fixed by someone who knows what they are doing). either issue could result in the play i've been getting, but i'd have to send the shock away to get it fixed, and i cant be without by bike at the moment. so, i bit the bullet, and purchased another mcleod shock, and this time went with standard bushing hardware. received the shock & hardware last week, raced it on the weekend, and the bike is totally perfect now. i'll look into getting the old shock fixed, but i am in no hurry. So, in conclusion, the play was not the bike, it was the shock.
over the last few months, i have continued to improve my results in XCO-format club races and longer 3hour events. it has been a while since i got worse than 3rd. I have been having the best time racing ever, with a few absolutely glorious finishes, often picking up some places in the closing stages of events of all kinds. i cannot imagine a better bike for these events. i have reached a crossroads recently, where my long-time goal, which was to get a top 3 B-grade overall series result at my local club, a goal which has more recently been upgraded to winning the series outright, is now looking like it will be realised - with 2 races to go, i'd pretty much have to DNF to lose the series now. So, feeling a little goal-less at the moment, the motivation not so good. need to find another goal. Naturally, going to A grade is the next step, but it is a big one. I'll do that next year, but A grade at my local seems to almost always feature guys who frequent world championships etc, so i certainly wouldn't be going for the win in those races. There are a lot of other races which have age-based cats, so maybe that's a better bet. In any case, i still have probably 5kg i could lose off me (without getting crazy thin), so there's a bit of speed to gain there. I certainly am not motivated to upgrade anything else on the bike, as I don't think there are any changes to do that would make me any faster.
i am so much faster now than people who beat me easily last year. I am trying to think of the reason why. i am barely 2kg lighter than i was about a year ago (note: i am still 1kg over the healthy weight range per BMI), the bike is maybe 400g lighter (mainly due to the Fox32SC fork). My power figures lately are pretty close to what they were this time last year - if they are higher, it wouldn't be more than 5%. I have been riding maybe 5% more hours than last year, a lot of the extra hours are races. I certainly feel more comfortable on the bike with the handling, and i spent a fair bit of time fine tuning the tyre pressures and suspension settings. i did move my cleats back a few mm which has reduced the tightness in my calves, and more recently i moved the saddle forward about 8mm. since about January or february, i have gone all in on oval chainrings (on all bikes), and i am starting to believe some of the claims (better endurance, lower HR etc), especially given how strong i have been finishing races. I suppose all the marginal gains add up. the bike certainly helps. super super stoked with it.
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Nice read. Thank you for posting !
I will build a full suspension in the coming months, I like the new Carbonda for the moment.
Maybe you improved your technique or confidence or both.
A friend goes much faster than me, not because of power, I get him as soon as it climbs a little.
But when it gets curvy or rough, I see him go. My guess is handling and confidence.
I improved dramatically last year after a racing week, but still lot of work to do.
At least for me, this is a non-marginal gain to get ;)
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yeah, i think the bike handling improvements have probably contributed more than i realise - after a year on this bike, i think i'm going into and through corners more smoothly, and exiting with more speed. i also certainly am pivoting around the sharper corners (e.g. switchbacks) better than when i first started riding this bike.
i think i also underestimated my fitness improvements. i reviewed my 2018 vs 2019 power curves, and it looks like my power is up around 7% (roughly on average, across the curve), which is more than i expected.
in a week's time i am gonna do a threshold-type fitness test, which involves a ~30min interval up a steady fire trail climb. i did it at the exact same time of year last year, and i do it on my powertap-equipped hardtail (my commuter reconfigured with lower gears and off road tyres), so, unless the surface is significantly different, it should be a good like-for-like comparison, to gauge if i have really improved fitness, and by how much.
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...i reviewed my 2018 vs 2019 power curves, and it looks like my power is up around 7%...
Congrats... this is no small feat.
When I compare them, 2019 looks better than 2018, but never 7%
This is about going 4' faster every hour.
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the numbers are in - the improvements were much more in the engine than originally thought. the fitness test today went much better than expected. over the exact same course (a gradual long climb), on pretty much the same bike (my hardtail commuter, converted to offroad, with a slightly different 1xoval transmission, and faster rolling rear tyre), with a very similar year of riding (maybe 10 extra hours so far this year, a few more races), i got power numbers that were a consistent 9-11% higher than last year over the targeted 5-30 minute part of the curve. the key ~35minute segment was done over 3 minutes faster too. was definitely attacking the steeper sections more. though it wasnt as painful as last year, i did average 2bpm higher.
well this explains the recent results a lot. dunno where this improvement came from. maybe my kids getting heavier has helped - more resistance towing them up climbs, when i do the twice-a-month trailer rides. or maybe there's more gains in that oval chainring (for me, at least). it is not like i have done much different, no structured 'training', just riding to work like i have been doing for years.
i still think my FM058 has helped though.
I am more motivated to do some more events after this. will do some more mid-length 3-4 hour endurance events. am more motivated to lose some weight too, as i am getting close to matching the really fast guys, and need to close the gap before taking the big step up.