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Discussion Starter · #1 ·
I just finished buliding up my new Flux today and took it out for the first ride, which ended up being a disaster.First steep climb and the chain would slip from the front middle chainring and make this god awful noise and then catch. I took the bike home and threw it up on the bike stand. It appears that in the middle chainring/large cog combo that the middle chainring is too far outward (so if I added any spacers the issue would be worse) so the chainline is all jacked up. Under power it's catching the edge of one side of the chain and causing it too slip for a split second before catching.

I'm using some older ISIS Race Face LP's with a new FSA Platinum quad bearing BB and new SRAM chain. The derailleurs are both adjusted properly. I also double checked to make sure the crankarms were "seated" all the way on the bottom bracket splines.

Any ideas here? Has anyone had the same issues with old ISIS RF cranks and a newer FSA ISIS BB? I just had this entire drivetrain on my old Yeti ASR (with the exception of the FSA ISIS BB and front der.) and it worked just fine.

Thanks,
MSH
 

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MSH said:
I just finished buliding up my new Flux today and took it out for the first ride, which ended up being a disaster.First steep climb and the chain would slip from the front middle chainring and make this god awful noise and then catch. I took the bike home and threw it up on the bike stand. It appears that in the middle chainring/large cog combo that the middle chainring is too far outward (so if I added any spacers the issue would be worse) so the chainline is all jacked up. Under power it's catching the edge of one side of the chain and causing it too slip for a split second before catching.

I'm using some older ISIS Race Face LP's with a new FSA Platinum quad bearing BB and new SRAM chain. The derailleurs are both adjusted properly. I also double checked to make sure the crankarms were "seated" all the way on the bottom bracket splines.

Any ideas here? Has anyone had the same issues with old ISIS RF cranks and a newer FSA ISIS BB? I just had this entire drivetrain on my old Yeti ASR (with the exception of the FSA ISIS BB and front der.) and it worked just fine.

Thanks,
MSH
...sounds like your middle ring is worn. Do you have another laying around you could swap out & try for a spin?
What is the spindle length on the BB? Sounds like the new chain + variance in chainline is flushing out your old chainring to me.
 

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... I guess you won't be
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race face middles do sit slightly more outboard than their shimano brethren [they're slightly thicker too]...I found this out the hard way when I replaced a RF middle w/ an LX middle.....I needed some spacers to get the shimano middle back into proper position.....it was definitely a WTF moment!

Another possibility is that the FSA BB's spindle is longer [wider?] than your previous BB spindle.....are you using a 113mm? If not, get some thinner BB spacers [they do make thinner ones] and shift the BB spindle to the left a little more to get that middle ring more centered. Or, are you not using any spacers....?

A fresh middle ring may also be a good place to start, especially since you've thrown on a new chain, and I assume an brand new cassette in back......if so, you know better!
 

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Natl. Champ DH Poser/Hack
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fer cryin out loud! is everyone afraid of a proper build and/or tune up? go to yer lbs! dependin on bay area labor rates, for $30 to $50 yould likely be ridin with a smile instead of wastein yer time here, bein frustrated and chasin yer tail. how much is yer time worth?

now before ya think me a ass, congrats on yer flux and im sorry yer 1st ride went bad. sounds like too many spacers on the drive side of the b/bkt or a mis sized spindle and possibly the dreaded new chain on old gears syndrome. im sure yer local shop could help.... unless yer skeered.
 

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cactuscorn said:
fer cryin out loud! is everyone afraid of a proper build and/or tune up? go to yer lbs! dependin on bay area labor rates, for $30 to $50 yould likely be ridin with a smile instead of wastein yer time here, bein frustrated and chasin yer tail. how much is yer time worth?

now before ya think me a ass, congrats on yer flux and im sorry yer 1st ride went bad. sounds like too many spacers on the drive side of the b/bkt or a mis sized spindle and possibly the dreaded new chain on old gears syndrome. im sure yer local shop could help.... unless yer skeered.
ive been asking myself that question ever since ive been following this forum... i figured that a guy that spends upwards of $4k on a bike must self build out of choice, part of the whole bike experience thing. but when you run into trouble why not scoot down to your lbs?
the other thing that's been bakin my noodle is why so many high end builds opt for mechanical disc??
 

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Natl. Champ DH Poser/Hack
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PSI said:
the other thing that's been bakin my noodle is why so many high end builds opt for mechanical disc??
ladies and gentlelemmings, i give you the avid bb7! cheap, kinda light, easy to setup and keep workin, any shop monkey can make it work, almost no hassle, fixable most anywhere with basic tools and supplys, plenty of power for most folks in most places, no bleeding, no mess, store it upside down, soft lever? turn a dial! i could go on.

one day ill go hydro, just not today.
 

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Discussion Starter · #7 ·
Thanks for input all.

So today I swapped over to some old XTR cranks and XTR BB, but the problem still was there. I took a closer look at was going on and the chain was pulling up off the bottom of the cranks when I would apply heavy torque to the pedals.

Anyway, I finally decided to throw on an old PC-69 chain to see what would happen...result = no more problems. I have been using SRAM chains forever and never had any issues. I don't know if they made some changes (I'm sure they must have) with these new PC-9XX (in this case I was using a new PC-971) chains, but it seems they aren't jivin' with my current mix of drivetrain components.

MSH
 

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New chain + worn rings = trouble.

Put on new rings (and cassette if it's worn) and put on a new chain and you'll be good to go.

The fact that an old chain worked shows that the rings are worn.
 

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Never enough time to ride
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Definatley sounds like the old worn chain rings/new chain syndrome. I've been using SRAM chains for the last 4 years or so, with one or two excursions back to Shimano when SRAM wasn't available, and have had very few problems. Link profiles have changed slightly and had a bit of a problem with one of the new (now old) PC 990 (now the 991) with a cassette, seems the outer plates bulged a bit to much and it didn't matter how it was tuned it always wanted to shift.

My current set up is Race Face Turbine ISIS w/ Signature series XS BB (113mm spindle), SRAM 990 chaing, and XT 11-34 cassette (sorry I don't think SRAM cassettes are quite there yet), X.0 Rear der, and X Gen Front der.

Like mentioned before, try a new set of rings and cassette (if you haven't replaced it already) and all should be good. There's also the old take to the LBS trick too, and having worked in shops for a little over 6 years now, I can vouch for most other shop rats when I say that it's better to take it in before you tear into it if your not sure. It's cheaper in the long run.;)

happy trails...

squish
 

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Natl. Champ DH Poser/Hack
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if the chain is dead, you can bet a beer the rings and cassette are dead too. these 3 parts wear together, not individually. thats a fact, jack! a little trick i use is to measure the chain periodically over a 12" area. if i see the pins at 1/16" over those 12"'s center to center its time to replace. if ya wait for the standard 1/8", its too late and yer where ya are now. a park chain checker is a even better tool but ill bet ya have a ruler already. some guys rotate 2 or 3 chains. same diff, just more work and a bigger expense up front. stick with the new scram chains too. the shimanos shift a tad better but dont last nearly as long. good luck with it.
 

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cactuscorn said:
ladies and gentlelemmings, i give you the avid bb7! cheap, kinda light, easy to setup and keep workin, any shop monkey can make it work, almost no hassle, fixable most anywhere with basic tools and supplys, plenty of power for most folks in most places, no bleeding, no mess, store it upside down, soft lever? turn a dial! i could go on.

one day ill go hydro, just not today.
Oops! sorry, didn't realize you're one of them :)

It was meant as a philosophical question; why blow the equivalent of a 3rd world country's annual budget on a bike and skimp on the brakes? (unless you just like em, which is ok too)
 

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PSI said:
Oops! sorry, didn't realize you're one of them :)

It was meant as a philosophical question; why blow the equivalent of a 3rd world country's annual budget on a bike and skimp on the brakes? (unless you just like em, which is ok too)
yeah, me and team sanchez. stuck in the dark ages of brake bling. if i didnt like em, theyd be in a box, not on the bike. i like em alot. matter of fact after my colorado trip with the hayes on the rfx and the bb7's on the flux, i much prefered the avids in every respect. that suprised me. the hayes mags are commin off and box bound. for sale. $100 for the pair. used once.
 
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