2x10 crank setup

[Lance Roberts]

Hi everyone,

 

I've got a question regarding the setup of my bike. I have a 2x10 Shimano XT setup.

Is it correct right that the Drive side crank arm is further away from the frame than the non drive side?

 

I have a 68mm BB, and so installed 2 spacers on the drive side and one on the non drive side.

 

I just measured the distances and the drive side pedal is a lot further away from the frame than the other side. Is his normal?

 

Before anyone asks, it's a Chinese Carbon frame, so there is no reference to any setup anywhere

 

Hope someone can help me because I don't want to ride the bike if it's going to affect my back or anything else. I've already had the most wicked back pains, but that was in the beginning of starting to ride it, and after fiddling with the seat hight and changing the handle bar it has now come right.

 

Hope to hear from someone .

 

Thanks,

 

Lance

[JXV]

The spacers are used for two things:

1) to get correct chainline and

2) to get correct BB width.

You can look up installation instructions for Shimano XT bb on the web.

 

If your BB width is correct then you have the right no. of spacers. Now you just need to decide how to split them between the two sides of the frame.

Your small ring should line up on or about the 3rd/ 4th largest cog on the cassette and big ring on about 6th gear. Move spacers from one side of bb to other as needed.

[Tony datoy]

My 2x10 setup on my silverback frame is the same as yours, 2 spacers on the drive side and one on the non drive side.

T

[Lance Roberts]

Thanks for the feedback guys. Just checked and at the moment the chain is on big in front and 6th on the back and the chain is not strait at all.

 

So I'll just play around with the spacers a bit to get a good alignment.

 

My biggest worried is that my right leg is a lot further away from the frame than the left one, and that it's causing a misalignment of my body when pedaling, especially when out of the saddle.

 

Will see what I can figure out.

 

Thanks again.

[NotSoBigBen]

Just a small question by how much is this 'out'?As I recall those spacers are not very big so can it REALLY make such a big difference ...... to your body that is, chainline is a different discussion!

[Lance Roberts]

Just a small question by how much is this 'out'?As I recall those spacers are not very big so can it REALLY make such a big difference ...... to your body that is, chainline is a different discussion!

 

Hi BigBen,

 

Thanks for the  reply.

I just measured it and the drive side is 1.5cm further away from the frame than the non drive side. I guess it doesn't sound like much but I just wanted to make sure. The spacers are 2.5mm each, so if i move both to the no drive side the difference should only be a 5mm. 

Is that a lot?

 

Also, the chain alignment will be better if I move the spacers.

 

I know that with crank lengths they say the difference between a 175 and 180 is a lot, and that's only 5mm...

[NotSoBigBen]

My personal opinion is just that with the spacers you will be able to make changes to the chainline if you really need to but it will have no effect physically to your body when riding.

 

I could be wrong but I doubt it 

[JXV]

What cog are you in when chain is dead straight on the big ring?

[rock]

afaik the BB spacers have nothing to do with chain line, its to make up the space if you're running a 68mm BB or 73mm BB. Purely crank fitment only.

[NotSoBigBen]

afaik the BB spacers have nothing to do with chain line, its to make up the space if you're running a 68mm BB or 73mm BB. Purely crank fitment only.

 

That was my thinking that it is such a little that it would not have a major bearing on chainline and or body?

[Lance Roberts]

What cog are you in when chain is dead straight on the big ring?

Hi Guys,

Thanks again for all the info.

 

Just had another look at the setup and I think I've been wasting your time. If I take the spacers out on the drive end the big gear will be too close to the frame.

So i think it'll have to stay the way it is.

 

JXV, just to answer your question. The chain is pretty strait when it's on the 4th gear from the bottom.

[JXV]

 

 

JXV, just to answer your question. The chain is pretty strait when it's on the 4th gear from the bottom.

Ok still confused...on your rear cluster the biggest cog is number 1 and the smallest is 10......

 

So 4th gear from the bottom (presume smallest) would be 6th and that would be more or less OK. You should be able to use all your 10 gears when in the big front ring but the two biggest ones ( 1st and 2nd) will likely grind a bit and should be avoided by switching to the small front ring instead.

[Lance Roberts]

Ok still confused...on your rear cluster the biggest cog is number 1 and the smallest is 10......

 

So 4th gear from the bottom (presume smallest) would be 6th and that would be more or less OK. You should be able to use all your 10 gears when in the big front ring but the two biggest ones ( 1st and 2nd) will likely grind a bit and should be avoided by switching to the small front ring instead.

 

Ok, then all is fine.

Sorry about the confusion. I thought when you said the 6th gear you meant from the bottom.

Cheers