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Messages - sandwich

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1
29er / Re: Ican S3 XC Frame
« on: December 18, 2023, 09:03:33 AM »
whelp, I bought what might be the last S3.  There was a sale that ended yesterday, so I scooped it up.  We'll see!

2
29er / Re: Carbonda fm936 Thoughts
« on: December 12, 2023, 07:55:28 AM »
This isn't an enduro bike, you are not going to experience pedal kickback at 100 or 120mm of rear travel. An additional pivot point isn't not going to add stiffness either, in fact it will do the opposite. Tune the horst link how? and why? Again, this isn't an enduro bike, it is an XC frame that has been built by a lot of people as a downcountry frame. As soon as you enter trail territory then, yes, go 4 bar and tune your shock all day long. The S3 is a weird frame in the modern bike realm, no major brand is using 4 bar for XC or light trail for many reasons, and if light trail is what you want then sure go for that.

I ride an over-forked 936 (120/100 Float DPS), and an over-forked 1001 (150/135 Float X), and have built and ridden a 130/120 (Float DPS) 1001. The 936 is so mush more stable while pedaling, and has no issue using the full travel when needed, and climbs like a rocket when compared to even the 130/120 1001.

Independent of your analysis, I have always been confused about locking out for climbing (unless its a hard pack fire road). Suspension will help keep the tire in contact with the surface so that you aren't just bouncing around...

uh, ok.  I'm not going to argue with you on the internet, especially if you are misinterpreting what I am saying.  I haven't ridden either frame, but I've been riding MTBs for like 27 years and have been trying to understand suspension since the very first full suspension mountain bikes (remember semi active vs fully active?).  Linkage blog and other resources have come out that help to plot how suspension behaves and helps to demystify awful marketing speak. 

Mobile Chernobyl asked about the differences between the two frames, it's extremely unlikely that anybody has ridden both, but based on the suspension analyses performed already and a fundamental understanding of translating them to practice, there are differences that trend in favor of the S3 in terms of suspension performance alone.  The FM936 has already been proven to be a great bike, and if you can't get the S3 in your size (it is discontinued) or can get the Carbonda for cheaper, then you aren't missing out on much- roughly 10-20% increase in anti-squat and slightly less anti-rise.  The difference between the two suspension designs is very marginal but it's also real- the brake is decoupled from the swingarm and the fixed instant center of a swingarm bike is changed to a migrating instant center which creates a bit more anti-squat. 

3
29er / Re: Carbonda fm936 Thoughts
« on: December 11, 2023, 09:22:33 PM »
Am I missing something? Isn't more suspension resistance what you want in a cross country frame? Especially when climbing and sprinting? And why the add the extra weight and complexity of a 4 bar suspension to XC? I'm very confused by this analysis and recommendation.

I wasn't thinking straight- the flex stay will likely ADD spring force, not take it away, making the frame even more progressive than it already is.  It will naturally want to return to its static position.  Again very difficult to tell without measuring the force at the axle.

In terms of performance, that doesn't really do anything at all.  You can tune for that within the shock (smaller air can, more resistance bands, etc).  What you want in an XC frame is likely 100% antisquat, or more, or a lockout and light weight.  Most of the most competitive XC frames all have a pivot height near the carbonda's (epic, scott).

You add the extra pivot for stiffness, reliability, better braking performance, and switching the suspension from single pivot to virtual pivot.  You can tune the horst link to do a lot of things, and the added anti-squat is pretty helpful in my opinion.  If you are looking at it from a pure XC point of view, yeah I'd probably go with the carbonda and a lockout shock, then slap that on any time you head upwards.  If you're looking for a trailbike to go have fun on, then I'd go with the S3 as the marginal improvement of the horst link with roughly the same weight and cost seems like a win to me.

None of this is to say the 936 is a bad frame- it's probably the best designed chinese full suspension bike I have ever seen.  The NS got rave reviews and this is basically that bike.  I just think the addition of the horst link and in particular its added anti-squat makes it a better buy.

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29er / Re: Carbonda fm936 Thoughts
« on: December 11, 2023, 05:27:49 PM »
Hey there, I haven't ridden either but I've stared at the charts long enough and understand them well enough to have an idea of how they might perform.  See these posts here:

http://chinertown.com/index.php/topic,3343.msg29072.html#msg29072

http://chinertown.com/index.php/topic,3198.msg27489.html#msg27489

The FM936 has ~20% lower antisquat values with the same size chainring (compare the 32t vs 32t plots).  I can't seem to link the images directly but @julian labeled his charts just fine.  What that translates to roughly is more suspension resistance to your pedal stroke- in my opinion the S3 will be a much better climber and sprinter and the 936 will be mediocre in all scenarios.  Not a bad ride but not a standout.

The leverage charts appear to be roughly the same and that makes sense.  There's an effect due to the flex stay that isn't there with the horst link, it's hard/impossible to quantify without advanced tooling.  I'm guessing the flex stay will cause some additional resistance as you get deeper into the travel which translates to a bit of a falling rate, but I think it'll be negligible in trail effect.

All in all, I think the S3 is an objectively better frame- it should pedal better, brake better (marginally) and have similar progression in the shock stroke.  I am looking at one for myself, but the question is really "do I need a new frame" and not "which one to get".  I'm 5'11" and I think the medium would be great...my current bike sits around 450mm and it's pretty darned comfortable and set up as a trail/enduro bike.  A 465mm reach XC/Trail bike should be nice and long and still manageable in slow speed turns.

5
29er / Re: Ican S3 XC Frame
« on: December 02, 2023, 08:50:58 AM »
Resurrecting this thread...are there any alternative suppliers to ICAN for this frame?  I'm interested in a medium but sometimes there are alternatives.

Geometry numbers are pretty dialed if they are accurate.  500mm reach on a large???  470 on a medium.  I'd run it with a 45mm stroke shock and 130mm fork (as that's what I have).  Should slack it out to ~65.5* and 465mm reach, raise the BB a tiny bit.

My BMC is getting tired and it may be time for a replacement.

6
Road Bike Frames, Wheels & Components / Re: Goldix/Evosid Dimpled Crankset
« on: September 20, 2023, 07:05:50 AM »
This is the lightest bang-for-buck (sub-$50 USD) crankset on AliEx. Yes they are a bit sketchy, but I love them! I have them mounted on my 1x gravel bike paired with a Pass Quest aero 1x chainring. I'm not sure if the hollowed out crank arms might affect your aero, but I'm guessing side winds won't be an issue. AliEX DIY hack is to toss the stock pinch bolts from the non-drive side and replace them with M5x25mm titanium screws. This will allow slightly higher screw torque at 8-9nm. Stock steel screws will start rounding out beyond 7nm and cause creaking under high torque at that torque range. Trace Velo had creaking issues and I believe it was due to the pinch bolts being inadequate.

https://www.aliexpress.us/item/3256804815422658.html



GXP/Direct mount 1x aero chainring (make sure to get ordinary if you're not using SRAM AXS):
https://www.aliexpress.us/item/3256804752779564.html



Okay so first off- I was under the impression that a chainring had to be compatible with the AXS flattop chain, but that most other chains were compatible with AXS chainrings.  Basically, AXS chains are special but AXS chainrings are not.  My intent is to run a YBN chain anyways, so I would go regular, but would prefer maximum compatibility if possible.  I reached out to Pass Quest and they want an extra $20 to customize for AXS compatibility.

As to that crankset, I'm not sure I'm ready for something so light with so many quite obvious corners being cut.  24mm aluminum spindle is already a risk, pinchbolts on an aluminum axle, and those spindly arms.... I appreciate the nod, but at 200lb that's probably not the right crank for me.

After all this discussion I'm probably going to end up sticking with my 105.  Rock solid and I can adjust the chainline without worrying about an offset ring.  Those solid Goldix cranks are tempting tough.

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Road Bike Frames, Wheels & Components / Re: Goldix/Evosid Dimpled Crankset
« on: September 17, 2023, 07:01:26 PM »
I'm running alloy axle cranksets, but more for weight weenie/climbing reasons. For time trials, does crankset weight make that big of a difference? They sell Pass Quest aero chainrings for the 105 if you're interested. I use their 1x aero chainring on my gravel bike and they're quite well made.

https://www.aliexpress.us/item/3256805545884713.html

I don't think that weight nor stiffness is that big of a deal on TT bikes.  Weight is certainly not (when compared with aero) and stiffness is really not critical as realistically you are not sprinting or climbing- you are putting 200-400w in a consistent manner through your drivetrain....not like hill climbs or crits when you are punishing your equipment in a sprint. 

Stiffness is still more important than weight IMO, so it would probably be aero-stiffness-weight for me.  I swapped to a new lighter bike recently, and it made little impact to my times as compared with positioning and gearing.

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Road Bike Frames, Wheels & Components / Re: Goldix/Evosid Dimpled Crankset
« on: September 17, 2023, 06:54:03 PM »
I would call this very much not aero. This is a copy of a cnc boutique hipster crank and probably about as aero as a bookshelf (as far as cranks go, being those tiny things, spinning all the time, with feet and legs attached to them and all that stuff ...).
Have you ever seen actual aero cranks? I mean, are you serious?

Feel free to disabuse me of this opinion. Always happy to learn new things.

Sorry, I can see how my post was confusing.  I am not looking for the most aero crankset- I honestly don't believe that cranks are really a good area to save watts when it comes to aero profile.  I am ditching my 2x setup for a 1x setup, and this provides me with an opportunity to rethink things.  One of those things is the entirety of my crankset/chainring combo.  Right now I have a chainring power meter and 5 bolt 105 cranks.  The cranks are fine, but if I have the opportunity to ditch 5 chainring bolts in favor of a solid direct mount chainring, that doesn't seem like a bad deal.

Again, not sure that any crankset is going to save significant aero drag, but almost everything out there even billed as "aero" is not different in profile than the one I mentioned, but rather features a dinner plate direct mount chainring with similar profile crankarms: https://www.competitivecyclist.com/sram-red-1-dub-12-speed-aero-crankset https://rotoramerica.com/products/flow-crankset-110  I think you are saving 0.5-3W maximum with any option, and I think you are looking at a 1w difference between the Goldix thing above and a rotor flow provided you are using a solid chainring.

So the questions is not "is the crankset above aero", but rather "Is a cheap direct-mount crankset with a solid chainring more aero than a good 5 bolt crankset with a Pass-quest thick but-not-solid chainring".  I don't know this is a question that anybody can answer without a wind tunnel, honestly (and I'm buying crap off aliexpress, I'm not paying for that)

Finally, regardless of all that I am primarily interested in whether these cranks are trash or if they are useable.  I am well aware that the dimples aren't going to make a difference, it's more of whether these can handle 800w and a few take-off and resinstallations without disintegrating (and whether I can make more money selling my 105/PM combo than PM alone)

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Road Bike Frames, Wheels & Components / Goldix/Evosid Dimpled Crankset
« on: September 16, 2023, 09:46:42 AM »
Not sure what to call this: https://www.aliexpress.us/item/3256805835501765.html?spm=a2g0o.cart.0.0.3e6d38dahJxoZc&mp=1&gatewayAdapt=glo2usa

I'm considering replacing my shimano 105 5 bolt crankset for something more aero for my time trial bike.  I need to have a 24mm spindle to work with my BB and frame.  I'm not overly concerned with weight, but low profile, stiffness, and fit is essential.

I've seen these "dimpled" cranksets from a variety of manufacturers, and they are quite cheap with GXP mounting and 24mm compatibility.  Some appear to have simple bolts and others as linked above  have a captive self-extracting bolt setup.  I'm not too afraid by the aluminum spindle as this is going on a road bike that sees a couple hundred miles a year and will likely never see a sprint at all.  Any experience?

10
I think an aluminum spindle is fine in the right application.  Mine would be going on a TT bike which will rarely see loads over 1000w, and minimal mileage all things considered.  I wouldn't use one on a mountain bike or sprinter bike, but even that might be fine with a light rider.

11
Component Deals & Selection / Re: Improved hoods for Sensah brifters
« on: August 27, 2023, 03:32:47 PM »
Do you have version one or version two of the hoods? The early batches had sloppy hoods, the newer ones is tighter and feels more grippy than the original. I have two version of Empire 11s and the hoods on the newer ones feels much better.

These are their new version https://www.aliexpress.com/item/1005003970724670.html there is no "graining" on the rubber, Gen 1 had the graining

I have what looks like the ones in the link above and the ones in OPs post. They are fine and comfortable, but they kind of slide forward and out of the ports/holes that they are supposed to stick into. I rode for a while not realizing there was a hole they were supposed to slide into, so it could be my fault. Either way, it’s my biggest complaint with the sensah phis that I run.

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Component Deals & Selection / Re: Best AliExpress head & tail lights?
« on: August 27, 2023, 03:26:46 PM »
I was wrong, it’s the BR800. They are pretty cheap and I may some day end up with a third. They just click right in so I have a mount on the commuter, road bike, and even Tt bike for safety.

13
Bumping this one too, as I'm considering buying this setup.  Looks like there are multiple from Zeroing, Cruzbike, and other labels.  I didn't consider a lack of self extracting bolt....hmmmm

14
Road Bike Frames, Wheels & Components / Re: Avenger Fm109
« on: August 26, 2023, 08:44:19 PM »
Posting in this thread mostly for posterity...but I am the owner of a Hongfu FM109 and while it's probably not selling much these days with everybody shifting to disc brakes, I can probably answer just about any question on it as I just recently built it up and have been enjoying it quite a bit.

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Component Deals & Selection / Re: Best AliExpress head & tail lights?
« on: August 26, 2023, 08:42:08 PM »
I absolutely love the Towild CL800 and now have two of them that I move between three bikes.  There's a flash mode and constant, and the flash mode is seriously bright- in mornings I can see the reflection on road signs as the sun is coming up.  Battery life is OK but not stellar, I think it died on a 4 hour ride but one of mine is a few years old at this point.  The garmin mount is slick and it charges via USB-C, which things seem to be moving towards.

Rear light I use a genuine RTL515 for the radar.

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