Carbonda fm936 Thoughts

[mobile chernobyl]

I am down to a decision between the newer 120mm version of the FM936 and a close sibling - the ICAN S3. Both will be running a 165x45 shock. I'm wondering if anyone has had a chance to ride the FM936 and the S3 back to back.

From what I've read the rear ends behave a little differently - it sounds like the S3 is both a better peddler and descender with it's slightly different kinematics.

I'd love to hear any subject feedback - otherwise it's a close race!

Thanks and this forum has a wealth of great info - thanks!

[sandwich]

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.

[zilcho]

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.

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.

[sandwich]

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.

[zilcho]

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.

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...

[sandwich]

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. 

[Ryan_M]

I've been talking with Wing (who's been fantastic) but it appears they will only ship with UPS. If they ship by sea they will not guarantee no damage. UPS is the worst of the worst, and coming into Canada somehow they find a way to set that bar lower. Has a one used the sea shipping?

[federic000]

Hi all so I’ve got my 936 in size M super light 120mm version. Happy with it, final weight should be around 10.2kg with bottle cage, protections and dropper post and pedals of course. SID ultimate for fork/shock, full sram x01 gear set, velosa wheel set

Pro:
Very good communication with carbonda / wing.
Frame quality and finiture are good even though I had to grind shock bushing a bit before insertion.
Painting looks strong (but has a small scratch on the rear brake mount).
Assembly was easy, BSA bb with crankset and derailleurs perfectly positioned and working fine.
Cable routing was also easy but I had to use a magnetic cable routing tool for the brake hose.
It’s not a clone!

Cons:
Delivery time took 2 full months.
Weight, frame at 2030 gr is not anymore super light as they claim it’s rather on the heavy side I think, if we compare with recent 120 mm competitors like spcycle, hongfu or tantan/seraph but I hope it will be strong and durable at least, Btw when this frame has been introduced weight declared was 1850grams (you can check on the internet archives) I don’t know what’s happened next.

[Mrbobbob]

How is everyone doing with long term durability? I have a second hand vitus. It looked immaculate when I bought it, but who knows how much use it had? I since put on about 1000 km before finding a crack in the drive side chainstay.
Sanding back it seems that the carbon on the bottom of the chainsay in this area was poorly consolidated (about 2 cm long). I assume given it was a narrow section that the bladder did not apply good pressure during manufacture. I assume that this is an uncommon issue.
[/img]

[ilyamaksimov]

How is everyone doing with long term durability? I have a second hand vitus. It looked immaculate when I bought it, but who knows how much use it had? I since put on about 1000 km before finding a crack in the drive side chainstay.
Sanding back it seems that the carbon on the bottom of the chainsay in this area was poorly consolidated (about 2 cm long). I assume given it was a narrow section that the bladder did not apply good pressure during manufacture. I assume that this is an uncommon issue.
[/img]

It looks like a crack chainstay in the drive side is a genetic problem with fm936, carbonda replaces such chaynstay under warranty

[federic000]

Guys do we know max torque value applicable to seat clamp? At 6nm my dropper keeps going down every time…carbon grease applied of course.
Thanks

[carbonazza]

Guys do we know max torque value applicable to seat clamp? At 6nm my dropper keeps going down every time…carbon grease applied of course.
Thanks

Did you check that the diameter of your seat post is precisely 31.6mm ?

[federic000]

Did you check that the diameter of your seat post is precisely 31.6mm ?

I haven’t, it’s a fox transfer SL therefore I can assume it’s ok! 
Anyway , at 7nm seems to be fixed. Thanks man

[federic000]

Hi guys
Anyone with a good fitting chain guard to suggest? Still haven’t found one that fits well
Thx

[dan_cx]

Hi guys
Anyone with a good fitting chain guard to suggest? Still haven’t found one that fits well
Thx

If memory serves, I used an Absolute Black guard mounted to an ISCG05 adaptor that mounts behind the bb cup. I'm away from my bike for a bit, but I'll try to get some pics up over the weekend.

EDIT: I had this pic on my phone. It's not my 936, but I used pretty much the same setup on my Revel Ranger. It's an ISCG05 adapter plate mounted behind the BB cup, and a Funn brand guard (amazon) mounted to it. Hope this helps you a bit.