I've got an LX touring chainset and I've been thinking the chainrings are too outboard of the BB shell causing a poor chainline. I removed it today to maybe swap over 1 or 2 of the 2.5mm spacers but found this plastic spacer on the axle. I removed it and the chainline appears to be a lot better.
Do I need it? I have checked all other hollowtech 2 chainsets in the house and no other one has it.
I think its No.19 on this [url= http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/FC/EV-FC-M581-2357C_v1_m56577569830608890.pdf ]techdoc[/url]
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I suspect the axle is designed to be long enough with it on there - won't the other arm 'bottom out' ont he splines and leave it loose in the BB?
It's probably there to increase the Q-factor and give more clearance around chain stays etc
That just looks like an oil seal to me ............perhaps from a previous bodge....
It's shown on here I think so probably meant to be there - number 14 - 6.5mm spacer?
[url= http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/FC/EV-FC-M583-K-2686_v1_m56577569830625626.pdf ]http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/FC/EV-FC-M583-K-2686_v1_m56577569830625626.pdf[/url]
That also looks like something thats not meant to be there.
Leave it on, make sure the BB cups are fitted with the correct number of spacer on both side - push the axle through, and put the other crank on.
Have a look at how far it sits onto the axle - I'm betting that your LH crank is not fitted onto the splines fully - post a pic here and we can compare.
In which case - I'd be carefully checking the splines on the inside of the crank for damage too.
EDIT now i've seen that diagram - so it might be a Shimano part, but I've still never seen or needed one. Try what I've mentioned above and see what happens, if it IS required to get the correct length, you could see if it will fit on the LH side between crank arm and bearing?
I bought the chainset new so it must be correct that it's there.
I left the spacer on and took this picture of the LH crank:
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This is it without the spacer - Note I can't run it without the spacer as axle is too long, doesn't allow me to preload the bearings.
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In the end I ended up leaving the 6.5mm spacer on and playing about with the BB spacers. I removed the 2x 2.5mm spacers from the drive side and replaced with 1x 1.5mm. The NDS now has 2x 2.5mm spacers. This set up still allows me to preload the bearings properly and has improved the chainline. Cranks are much more centred to the frame also.
What width is the BB shell on the frame? What number is stamped on the drive side crank arm?
Your last picture shows a large cap between the inside of the crank arm and the bearing cup. I would imagine that this allows some side to side movement.
What width is the BB shell on the frame? What number is stamped on the drive side crank arm?
Your last picture shows a large cap between the inside of the crank arm and the bearing cup. I would imagine that this allows some side to side movement.
Yes, that's without the 6.5mm spacer, as he said, the axle's too long. He's put it back in and shuffled the spacers.
Cranks are much more centred to the frame also.
If the cranks sit more centrally with the spacers 'wrong' I'd suggest your frame may be rather wobbly.
Are 'touring' frames designed with a wider chainline than mtb's? Might explain the issue with fitting the 'wrong' chainset to an mtb?
BB shell is 68mm. It's a Long haul trucker frame.
I don't think the frame is wobbly, I've had a good look and everything appears square. The wheel sits centered anyway.
I don't know if touring frames have a wider chainline, bit I've had and fitted quite a few HT2 chainsets and never encountered this spacer before. It really just seems to push the chainrings out too far.
Feels like a different bike now. No knee pain and no constant grinding noises. Gear changes are smooth and quick. And the front mech does a much better job now.