Aargh! Chainring touching the chainstay!

My_Teenage_Self

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Dammit.

It's taken me a while to get the bits together, and now this happens.

What options have I got?

I don't think I want a longer axle BB, the one I have is 122.5, and the arms are a good 20mm from the stays already.

Were any frames made specifically for compact rings? (this is a 'standard' set)

Cranks are Middleburn RS2s.

Any thoughts guys?



:( :(
 
Sounds like it could be your middleburn spider, it could be for a single chainring downhill and probably not for triple chainrings not 100% though
 
Trek 9800 OCLV, and the spider is 100% a triple.

Pics coming in a few minutes...

I measured, and it's actually only 10mm arm/chainstay... 45mm from centre ring to centre of seat tube?
 
Interesting, I have just recently purchased a Orange C16R from eBay, and the previous owner stated that he had a big issue with the crank rubbing the frame if he tightened the crank on to the BB, upon getting it home I stripped it down and to my suprise he had been riding it with the BB in the wrong way around. It was a sugino crankset with middleburn rings and shimano BB, now I'm not saying this has happened to you, just thought id share this with you :)
 
Interesetingly, it appears the previous owner had the same issues (the damage is paint only, thankfully)

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Longer BB? (which will be fun trying to find a longer one :()
 
My Zaskar has a 127mm axle to clear the perfectly normal M730 XT chainset from the super thick rear stays. Looks like you have a similar problem.
 
Middleburn say chainline should be 50mm, measured from centre of BB to middle chainring. Sheldon Brown also says that if the Seat tube is a larger diameter this also places the front mech further out.
Either way it sounds like you need a longer axle - 127mm?
 
I'm no expert at all but you could try to source an old Tune Titan BB. I use one of these myself and it is 124,5mm.
Hope this helps.
Adam
 
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