Fast 1x11 gearing on carbon frame - YFY-BM-01 or WCB-M-062 or other?

[Jerryno]

Which frame has been more proven and which would be better to get?

• YFY-BM-01: http://www.yfy-carbon.com/en/pro_detail.php?id=20

       

• WCB-M-062: http://www.workswellbikes.com/web/view/149.html

       

• Any other frames out there?

I like the workswell geometry better and I don't like the YFY head, but workswell seems to me unknown and unproven.
Also I need to note that I would like to fit 40T chainring 1x11 SRAM up front (does anybody have 1x11 setup on chiners and is the clearence between frame and chainring plenty to fit this huge ring?)

[Vipassana]

I can't answer anything about the frames, but a 40T front ring is REALLY tall... Have you ridden an 1x11 setup yet at length?  I use mine as an MTB and road-going bike several times a week.  Unless you're an absolute animal, I think you'll find that the 32T or 34T ring is plenty.  I don't have the official numbers in front of me, but assuming a 29" wheel diameter (at the tire), 32T front ring, 10T rear cog, and 80 rpm cadence, you're looking at 22mph.  At 100 rpm cadence, you're looking at 27 mph. 

With the 34T, its 23.5 mph at 80 rpm cadence and 29.5 rpm at 100 rpm cadence!

Do I run out of gearing on fast downhills with the 32T?  Yes, on occasion.  But I figure 27+ mph is as fast as I need to be bombing down a trail at.  There is always a 34T if I wanted to tickle 30 mph.  I will routinely cruise on the road in the 10T cog.  That's where the 34T might be better.  But come the uphills, I'm glad for the 32T.

Gearing strategy aside, there is also the physical limitation to consider.  Most 29er frames cannot support a 40T chain ring, XX1/X01 crankset spacing and while still allowing wide tires.  The 32T is very close to my frame to start (IP-256).  Furthermore, the 11spd chain is probably NOT long enough for the 40T/42T combination and would require you to combine segments from a second chain.  This of course would mean you'd have a loose chain and fully retracted derailleur when you went to go use the 10T cog, likely resulting in rubbing, bouncing, and chain loss.

My advice: buy a 32T and see where that gets you.  You might be very surprised.  If you feel you have strong legs and need speed, jump to the 34T.  But beyond that, I think you will only have issues in both gearing and function of the system.

Please take this question in the good spirit with which it is intended, but have you had experience with a 29er or the 1x11 XX1/X01 systems?

[Jerryno]

I don't have much experience with 1x11 (only on a test bike) but its the only option I would consider. Currently I have shimano XT 3x9 44-32-22 and 11-32 casette. This setup gives me top gear ratio of 4.0 and in 3 years of daily biking I used the small chain-ring only once - it's pretty much useless to me. The slowest gearing I use is 32T/32T 1.0 which gives me about 6mph or 9-10kph uphill - any slower feels like not moving:)

On flat terrain I usually use 3.67 or 4.0 when slightly downhill. I have very strong legs (am a big heavy guy - not very agile). Couple times I tried not using those gears if I would miss them and I found that yes..I needed to pedal faster (but with less effort) which I felt was tiring me more. The truth is 70% of time I am between the range of 2.3 - 2.9 gearing. I am like a cyclocrossing MTBer because sometime I go over jumps or terrain that would hurt non-mtb bike..

I don't want to go with 3x9 again (the small wheel is dead weight). As any current 2x10 systems don't offer anything close to 3.6 or bigger ratio, I am left with sram's 1x11. With 40T front 10-42T back this would gave me ratios from 4.0 to 0.95 which is more than I use. I plan also to install http://www.oneupcomponents.com/products/x-cog-44t-sprocket to make the cassette 10-44T just in case of some really tall hill. I could go with 38T front but not any lower - I would pedal myself to death:)

The frames should be designed to fit 3-chainring crank, but I have a feeling that the big ring in 3x9 is more offset from the frame than a 1x11 would be, right? So hence why I am concerned. If someone running 1x11 could check how much clearance there is and if it would be possible or not to fit big ring that would help a ton. The 38T chainring should be 6.05" in diameter and 40T ~ 6.37" (thats 15.36cm and 16.18cm) plus some gap to the frame.

[Vipassana]

Are you coming from a 26" wheel?  From the 3x9 claim, I think so?

Don't forget that the 29" wheel covers much more ground than the 26" per rotation and are typically geared different as a result.  Wheel size must be considered with the gearing you choose, not simply the ratios.  2x10 was developed for 29" wheels.  That is why it doesn't need to match the ratios delivered by the 3x9 systems of the 26" bikes.

For example:  A 3.6 ratio on a 29er at 80 rpm cadence give you ~25mph.  The same 3.6 ratio on a 26er at 80 rpm cadence gives you ~22.25 mph.  That's why you need a 4.0 on the 26 inch bike, to get you the same ~25 mph.  Ratio cannot be considered alone without wheel size. 

But I still fail to see how you would pedal your brains out with a 38T or lower?  36T x 10T is still 25mph at 80 rpm cadence.  And that's a fairly normal cadence.  But everyone is different and I understand that.

But regardless of if you can fit the front chainring or not, you still must understand that you will have TOO much chain for the system.  There is a strong chance that in the 10T, your chain will be too loose to ride.  The rear derailleur can only take up so much slack.  This is why SRAM says they system can only be used with a maximum of 36T front ring and 42T rear.  If you run a 44T rear and a 38T/40T front, they system cannot maintain chain tension.

But, to answer your question, on all of the 29er carbon hardtails I've looked at (IP-057, IP-256, IP-036), a 36T chainring is the largest XX1/X01 the frame can physically fit.  You are correct, the chainline is closer to the frame on the XX1/X01 systems than on the other 2x10 systems.

This is not a very good picture, but here you can see how close my 32T X01 is to the frame:


I'm certain anything larger than a 36T will not fit this frame and many others.

[Jerryno]

Well that is bad news for me, thanks for the photo, that is what I needed! Nope I have 29er now with this 3x9 on-demand drivetrain for top speed (the bike before this I had was cross and had 48T). I just really like to be able to go fast (35+mph) while not pedaling much..

[final forum]

Unless your racing harder then Nino, a 30-34 tooth is more then enough on a 1x11 setup. He rides a 36 which is still crazy. I used a 34 on a roller trainer this winter and still felt pretty decent. Just order a spider-less 30-34 chain ring on a 1x11 setup and you will be happy.

The avg guy I ride with goes on a 28-32 cause your not going to be needing that speed on any uphills. But each to his own. good luck.

[RS VR6]

Where besides going downhill can you consistently ride 35+ mph?

[Jerryno]

Many of you think a slower gearing is way enough fot mtb, maybe I have bad habbits..should I get use to pedal with more RPM on straigts? Is cca 90rpm cadence normal?

I come from cyclocross when I was younger, the rings have usually 38-48T, such drivetrain now would be: https://www.sram.com/sram/road/family/sram-force-1
I wouldn't consider mtb before because of small wheels, but when 29ers became available I went for one because I could use sturdier frame and suspension fork. So I build a mtb cyclocrosser. I don't want to go back because with mtb I can go down rough terrain with confidence and ease. Now I want a full carbon mtb which would be even closer to cyclocross because of weight but sturdy as a mtb - a win-win.

Where besides going downhill can you consistently ride 35+ mph?

Now about the speeds. You are right, can't go 35mph consistent on anything other than a decline or wind from back, 35+ downhill. Usually on flat road I cruise 25mph but with low rpm. Catching road bikes with cyclocross gearing is totally possible with snakeskin tires, the mtb accelerates slowly though (this I want to fix with carbon) and wind resistance is a little problem in long-run. I pedal somewhere between 60-80 rpm.

Unless your racing harder then Nino, a 30-34 tooth is more then enough on a 1x11 setup.

I don't race with this bike, well I would suck with my gearing on a mtb racing track you are right:) there would be no chance to exploit the fast gears - even not on downhills since the tracks are build to be technical. The bike I need is a daily commuter to go well on gravel and road but to handle also terrain and a 200lb/90kg guy. Should I have 2 different bikes? I do daily commute and weekend roadtrips on mix of road and offroad, very similar to cyclocross track.

I see lot's of people getting mountain-bikes but then cycling on flat roads the whole life (at least here in europe). I would consider true mtb gearing if I would bring my bike in car to the woods and then have fun there.

[325racer]

Just to confirm, most of the guys here are talking Miles Per Hour, is the OP of the thread talking Kilometers per hour???    Cause 6mph on some uphills and 35 mph is Road speeds not mtb speeds.

[Jerryno]

I measure in km/h but I tried to convert to mph..

Ok just back from a ride. I need to correct the rpm I am comfortable with, its more than I said earlier: like 90 - 120 rpm and 70-90 when chilling. The speeds I travel are uphill 10km/h, flat 30-40km/h, decline or wind 40-45km/h and downhill anything upto 70km/h. I could live without the 4.0 ratio right now and maybe also without the 3.8 if I get use to pedal faster. The 36T ring I reckon I can fit.

But still I would be so happy to be able to build this mtb/cross bike, today I will devote myself on finding if there is such a frame. I'll post any findings..

[RS VR6]

I keep forgetting that a lot of the members here are in Europe and use kph. 

You might actually be better off using a cross bike vs a mountain bike. It seems to make more sense if you plan to commute with it and don't do anything more than gravel.

[Carbon_Dude]

And you are probably better off with a 2x10 (or 2x11 road) gear train.  Even a 3x10 might be something better for you since you seem to have different needs with respect to high gear, low crank RPM.

[Jerryno]

So after some searching and investigating it is coming down to YFY frame and 2x10 sram setup with 28-42T rings. Here is a picture of that frame with 26-39T so a little bigger should fit imho.



2T difference on sram chainring means 4mm in radius (got this from sram's specs), so that means 6mm larger ring which would be close. Here are the radiuses if anyone would be interested: 36T=76.5 mm, 38T=80.5 mm, 40T=84.5mm, etc.

I couldn't find a frame to accommodate bigger than 36T in 1x11 setup. The ring has same radiuses as before and is 49 mm from the BB centerline for anyone that would like to measure clearances.

Also I found that putting a chain guard is a problem, same problem with frame clearance.

I also stumbled upon on some microdrive cassette with 9T-32T cogs for shimano, but this product is discontinued because to torque transfer on that 9T cog sux..

[cmh]

Unless your racing harder then Nino, a 30-34 tooth is more then enough on a 1x11 setup. He rides a 36 which is still crazy. I used a 34 on a roller trainer this winter and still felt pretty decent. Just order a spider-less 30-34 chain ring on a 1x11 setup and you will be happy.

My Cat 1 racer wife uses a 36 on her XTR 1x11. I offer this information for no reason other than shameless bragging. She's awesome.

[Vipassana]

My Cat 1 racer wife uses a 36 on her XTR 1x11. I offer this information for no reason other than shameless bragging. She's awesome.

Your wife is an animal.  And I mean that as a compliment. 

I'm thinking of stepping up to a 34T, 36T would be pushing it for me... too weak and too fat.

I wish my wife would race.  She rides, but not on an MTB.