Help I've run into an issue

[Perrin21]

Hi, I've just fitted an xtr952 crank to my bike and I'm getting some issues with the chain catching on the rivets on the chainset. It's just a tap every revolution but it's not smooth as it should be. I removed a 110mm bottom bracket and replaced with an octalink dura ace 7700 109mm but it seems the arms are too close to the frame so I'm assuming it's too small. What would be the best octalink v1 bottom bracket to fit in replacement that would work better? Here's some pics

 

[itscervo]

If you read your pm's it would have saved you a lot of time & money.
Anyway the answer is probably 112mm.

 

[ishaw]

Does it do this in all gears or just a certain combination?

As iscervo said, the correct BB size is 112.5 or 116 (I think), though I would be surprised if 1mm each side would make such a difference and cause rubbing, I've used a 105BB without issue in the past, Dura Ace as well if memory serves.

In terms of how close to the frame can you go, I asked once as I thought I had a build that looked too close on, but was told it was OK, and it looks to be around the same as in your pics, possibly a little closer.

This may sound a daft thing to ask, but what chain are you using? I've had some odd issues with certain chains that simply didn't seem to want to work with my set up despite being appropriate for it.

 

[Perrin21]

Re:

The chain is a narrow kmc with a Z on the link. I got it from the local bike shop. It's been fine with my old LX Chainset but isn't happy with the XTR952

 

[Perrin21]

Re:

I got the dura ace to try and save some money on the XTR bbm950 as I couldn't find one at a reasonable cost in decent condition.

 

[Perrin21]

Re:

I've been thinking, could it be the chain? The crank is a mega 9 crank but I'm running with an 8 speed XTR950 cassette. Is this a potential issue that's causing the catching on the front chainrings?

 

[My_Teenage_Self]

I'd say you should try a 9 speed chain.

 

[Remko]

Re:

A 8 speed chain on a mega 9 chainring should be no problem.
But it doesn't work on a 9 speed cassette.
A 9 speed chain on a 8speed cassette doesn't work either.

 

[Perrin21]

Re:

I found this info last night. I'm going to go buy a super narrow chain today. Seems I may need a front deraileur too frustratingly.

 

[Thias]

The problem ist the bb. Its too short. For v1 spline there is only two options. And both are XTR BBs. Dura ace us usually too short. (To check this, measure the chain line: middle of seatstay to middle ring should be between 4,5 to 5 cm)

So u're left with BB M952 or M950 basically.