Carbonda fm936 Thoughts

[reddi]

My FM936 build. 10,35 kg without pedals. Pretty light regarding it has a dropper post.

Wow, nice!
I like the clean look. It is a bit disturbed by the wheelset's decals. Maybe consider they are still recognisable without labels

[adroitrider]

Anybody try and get a crash replacement? What is the policy?

[ilyamaksimov]

Anybody try and get a crash replacement? What is the policy?

are you kidding? things broken through the user's fault are not subject to warranty replacement

[Julian]

are you kidding? things broken through the user's fault are not subject to warranty replacement

He's talking about crash replacement, not warranty. Google it.

[Julian]

Has anyone actually measured the travel of this bike with 40mm and 42.5mm shocks?

With the X3 linkage software, I always got more travel than it's supposed to have. I thought it must be the flex stays that I can't properly account for.

But now I compared it to the NS Synonym and it seems like all the linkage points are exactly the same (see image below). Only the flexing seat stay is slightly higher up, but that can't make that much of a difference.

I think the only real difference between the NS rear triangle and the Carbonda version is that NS put the bridge between the seat stays closer to the tyre, so that it can move further towards the seat tube and take that 45mm shock.

So if my theory is correct, the FM936 should have more travel. Exactly like the NS Synonym, only that you can't run a 45mm shock.

Which would mean:

37.5mm = 100mm
40.0mm = 107mm
42.5mm = 113mm
45.0mm = 120mm (theoretical, not possible)

[carbonazza]

Anybody try and get a crash replacement? What is the policy?

Sorry to see that... It must be saddening.
I would buy some UD carbon cloth and epoxy resin.
And wrap this unfortunate hit with them.

They will probably sell you a rear triangle if asked politely.
But I didn't ear they had a crash replacement policy, but who knows, you can and ask saying we are many here and it would give us some relief 

[adroitrider]

Sorry to see that... It must be saddening.
I would buy some UD carbon cloth and epoxy resin.
And wrap this unfortunate hit with them.

They will probably sell you a rear triangle if asked politely.
But I didn't ear they had a crash replacement policy, but who knows, you can and ask saying we are many here and it would give us some relief 

$440 shipped for a new rear triangle. Not bad.

But, I already have the carbon sheet and resin. Wing recommends repair as it is not a high stress area of the frame.

I have a similar puncture in my Flyxii top tube that I never fixed…might do them both at the same time.

[RobertRinAustin]

Has anyone actually measured the travel of this bike with 40mm and 42.5mm shocks?

With the X3 linkage software, I always got more travel than it's supposed to have. I thought it must be the flex stays that I can't properly account for.

But now I compared it to the NS Synonym and it seems like all the linkage points are exactly the same (see image below). Only the flexing seat stay is slightly higher up, but that can't make that much of a difference.

I think the only real difference between the NS rear triangle and the Carbonda version is that NS put the bridge between the seat stays closer to the tyre, so that it can move further towards the seat tube and take that 45mm shock.

So if my theory is correct, the FM936 should have more travel. Exactly like the NS Synonym, only that you can't run a 45mm shock.

Which would mean:

37.5mm = 100mm
40.0mm = 107mm
42.5mm = 113mm
45.0mm = 120mm (theoretical, not possible)

I measured mine with my 42.5 and got about 117 mm. I didn't push too hard into the stays, so there may be a bit more. I keep thinking I'll try it again and snap some pics.

[Julian]

I measured mine with my 42.5 and got about 117 mm. I didn't push too hard into the stays, so there may be a bit more. I keep thinking I'll try it again and snap some pics.

Thanks!

I've made a mistake though, the Synonym doesn't run a 45mm... But it makes no sense that 37.5 is 100mm and 42.5 is 120mm. That would mean a leverage ratio of 4.

I suspect the 37.5 has slightly more than 100mm and the 42.5 has slightly less than 120mm. That's also what my software is telling me for the FM936.

I actually believe now that the leverage ratios of FM936 and Synonym are pretty much identical.

For the FM936, the software says:

37.5 = 102mm
40.0 = 108mm
42.5 = 115mm

That fit's with your measured 117mm, especially if you pushed and made it flex a little.

Interestingly, the FM936 with 42.5 shock has more travel than the Ican S3 with 45mm shock. The Ican is more progressive though.

[InsaneDawe]

Yeah, I remember a while back someone put some force on his frame and found similar travel. Didn't have the time to find the post #. If I have time, I'll also try to measure actual travel on my 42.5mm shock. NS states the TR1 to have a 42.5mm shock & ~120mm travel.

[mtbluvr68]

Julian ,  From what I understand the FM936 at 42.5 mm shock is basically 115mm rear end, so your calculations are pretty close.  And that rear stay has some flex. 

[Julian]

Julian ,  From what I understand the FM936 at 42.5 mm shock is basically 115mm rear end, so your calculations are pretty close.  And that rear stay has some flex. 

Yes, I calculated exactly 115mm of actual travel. Plus whatever the flexing seat stays still give, but I don't count that as "real travel".

[adroitrider]

Yes, I calculated exactly 115mm of actual travel. Plus whatever the flexing seat stays still give, but I don't count that as "real travel".

Are you measuring actual shock stroke on a bike you have setup with a 42.5? My XL with a 42.5 does not achieve full stroke regardless of what PSI I run. I get 40mm of stroke on a 42.5mm shock.

[ilyamaksimov]

Are you measuring actual shock stroke on a bike you have setup with a 42.5? My XL with a 42.5 does not achieve full stroke regardless of what PSI I run. I get 40mm of stroke on a 42.5mm shock.

0 psi?

[Julian]

Are you measuring actual shock stroke on a bike you have setup with a 42.5? My XL with a 42.5 does not achieve full stroke regardless of what PSI I run. I get 40mm of stroke on a 42.5mm shock.

I didn't measure anything, I just calculated the theoretical travel with a linkage software (see images below).

But a 42.5mm shock should give you exactly 42.5mm of stroke length. If it doesn't, then I'd open it up and see if there isn't maybe a stroke reducing spacer in there. The 40/42.5/45 mm shocks are all identical except for a 2.5 or 5 mm spacer.

Try compressing it half way and holding it there before you start letting air out. That way the positive and negative air chambers can't equalize and only the positive air chamber lets out air, making the negative air pressure push the shock into full compression.