Author Topic: Carbonda FM909  (Read 162339 times)

carbonazza

Re: Carbonda FM909
« Reply #555 on: November 06, 2022, 08:51:31 AM »

Pedaldancer

Re: Carbonda FM909
« Reply #556 on: November 06, 2022, 11:54:33 AM »
Then I'm not sure why he was talking about chainring clearance, if they're just QF difference.

Because at a certain point it's not possible to further reduce the q factor on a crankset without reducing the chainline ... otherwise your feet would crash the chainring... this is why the reduced QF comes with a reduced chainline in this case.
« Last Edit: November 06, 2022, 11:57:29 AM by Pedaldancer »

Eneen

Re: Carbonda FM909
« Reply #557 on: November 06, 2022, 01:54:58 PM »
But XTR crankset has reduced 162mm qfactor with 52mm chainline. I don't know why Shimano doesn't make low-q xt's:
https://bike.shimano.com/en-US/product/component/xtr-m9100/FC-M9100-1.html
This one will fit 909 with ease.
But I've found, that my current 175mm qf XTs are ok for light trail use, could be bit narrower so I will get 172mm. That's why I'm after this frame, all new frames are coming with 55mm chainline, so you can't use narrower qf cranksets.

carbonazza

Re: Carbonda FM909
« Reply #558 on: November 06, 2022, 03:52:42 PM »
...all new frames are coming with 55mm chainline...

What new frames are you referring to?
55mm chainline gives a heavily crossed chain on the biggest cog of a non super boost rear hub.

Eneen

Re: Carbonda FM909
« Reply #559 on: November 06, 2022, 04:30:23 PM »
https://bikerumor.com/aasq-142-why-are-brands-moving-boost-frames-from-52mm-to-55mm-chainlines/
Yeah, that makes me mad too. I currenly have 57mm chainline in my hardtail (outer chainring position on triple bcd104) but I've got 445mm chainstays, so it's very similar to 55mm on 430mm chainstays. And this honestly sucks, industry pushes this due to tire clearance/short chainstays combo.
« Last Edit: November 06, 2022, 05:05:12 PM by Eneen »

Zomb1e

Re: Carbonda FM909
« Reply #560 on: November 08, 2022, 05:31:19 AM »
https://bikerumor.com/aasq-142-why-are-brands-moving-boost-frames-from-52mm-to-55mm-chainlines/
Yeah, that makes me mad too.

So in a few years industry should move either to super boost as standard or to asymmetrical chainstays

RDY

Re: Carbonda FM909
« Reply #561 on: November 10, 2022, 01:33:22 PM »
Today was build day.  Combination of heatgun and scalpel and a bearing press dealt with extracting the painted-over bearings in all but one of the pivots.  It was a long, laborious process which the mechanic didn't enjoy, and it should not have been necessary but for the carelessness of the painters Carbonda used. 

Unfortunately we couldn't extract the double bearings in the middle linkage.  As there are two on each side I suspect it's not easy at the best of times, but per the photos, there was a large amount of clearcoat penetration of the bearing recess (worse than all the others) and they're completely stuck fast.  There's no way to remove them without using force sufficient to destroy the linkage. 

As such I emailed Carbonda requesting a new, painted middle linkage and bearings, to replace the current one when the bearings fail - which I can't imagine will take more than a season as we have fine dust like icing sugar here. 

Aside from all the time spent on that, things were relatively trouble free until it was brakes time. 

Titanium planet magura bleed screws refused to seal the caliper, despite looking identical to stock ones. Took ages to diagnose what the issue was as they weren't leaking visibly initially but all pressure was gone.   Then we discovered Hope floating rotor attachment points don't clear magura MT 2pot rear calipers. Going to have to swap the XTR one from gravel bike in.  Also forgot I needed a PM 160->180 adapter for the Manitou R7 Pro, which fortunately the LBS had.

Both the mechanic and I felt the Acros headset bearings were significantly worse quality than the ones provided by Carbonda. Also the IP seal that Acros provide to go between the bottom of the headtube and bearing results in play and won't work. Crown race they provide is also not split and won't work on the R7 Pro, or I suspect many other forks.    So we used the original  Carbonda bottom bearing and crown race, and the Acros upper bearing, cable routing insert and headset cover that I needed for integrated cabling with the Syncros Fraser bar. 

Hopefully finishing it off tomorrow. 
« Last Edit: November 10, 2022, 03:58:15 PM by RDY »

RDY

Re: Carbonda FM909
« Reply #562 on: November 11, 2022, 10:35:59 AM »
Finished.

Looks good I think.  Frameset appears to be very good quality.  Just a shame that the experience has been somewhat marred by the paint (clear) over bearings fiasco.  I'll update when I receive a response to my request for a new middle linkage to replace the borked one. 

First order of business, more shock and fork pressure.  Need to cut bars further and find the fattest grips available.  Also need a longer travel (and thus longer) dropper as I can't put seat high enough.  SRAManoruk and Shigura working well.  Also need to reduce saddle downward tilt as I can't get away with that on wide flat bars (vs narrow drops).  May ultimately have to change cockpit solution to something with rise and more backsweep.

Excited to ride it in the mountains and on the trails.  But god damn does lwb and wide bars feel like shit in the city.

Pics attached.

Rickbe

Re: Carbonda FM909
« Reply #563 on: November 11, 2022, 02:15:36 PM »
My son on the fm909.

acedeuce802

Re: Carbonda FM909
« Reply #564 on: November 11, 2022, 03:11:42 PM »
RDY, which handlebars are those?  Syncros or chiner handlebars?

Edit: Missed your previous post that they're Syncros Fraser with Acros headset. 

Great looking build!
« Last Edit: November 11, 2022, 03:56:20 PM by acedeuce802 »

carbonazza

Re: Carbonda FM909
« Reply #565 on: November 11, 2022, 03:17:14 PM »
RDY, which handlebars are those?  Syncros or chiner handlebars?
And the cassette?

RDY

Re: Carbonda FM909
« Reply #566 on: November 12, 2022, 04:15:50 AM »
Yup, Syncros Fraser IC SL DC 760 /50, with the complementary stem cap mount for the Garmin.  I'm not sure if it's going to be sustainable long term though.  I may need more rise and backsweep - especially once I get a new dropper that will raise my seat height another ~3cm.

Garbaruk 10-52 Micro-Spline, with XTR 12s chain and Garbaruk 36T oval narrow wide chainring.  Obviously SRAM AXS derailleur.   Hence SRAManoruk.

ssparks

Re: Carbonda FM909
« Reply #567 on: November 12, 2022, 10:34:51 AM »
Complete. First ride and video coming soon (eventually).

I’m very impressed so far.


carbonazza

Re: Carbonda FM909
« Reply #568 on: November 12, 2022, 12:44:43 PM »
...so jealous to see the color I wanted on all these bikes now 8)

Eneen

Re: Carbonda FM909
« Reply #569 on: November 12, 2022, 03:26:11 PM »
Is it clear tinted transparent or with speckles?