 You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
Hi. I just bought a hollow tech 2 BB and crank for my mmmBop.
It has a 73mm BB. The instructions seem to show that I need 1 spacer on the drive side of the BB and none on the left side. But that seems to put the chainwheels too far out. And the derailleur isn't working 100%.
Is it ok to remove the spacer? Or does it have to be there for some reason?
Also, the chain drags on the back of the front derailleur. Like the derailleur is installed too low. But if I raise it, the derailleur hits the large chainring when shifting up. Is the seat tube angle of the mmmBop different?? So I need a different front derailleur that suits the different seat tube a gle??
Thanks for any comments.
shove the spacer on the NDS if its an issue
Yeah. I might try that. But the instructions specifically say the spacer goes on the drive side. This is probably to centre the cranks?? But I would rather have the better chain line that I get without the spacer on the drive side.
Just do what gives you the best chainline.
Go 1 x 10 anyhow
Put it where the chainline is right. Are you absoulutely sure it's a 73mm shell? Measure it if you haven't, don't trust website specs, Mmmbop quality control wasn't high enough to make sure all the parts were straight and painted never mind whether the shells were the right width. Can't remember what shell mine was but it gave me no bother though.
Mine's 68mm.....
mine is 73 with a spacer on the drive side.
I originally had spacer problems and contacted Ragley way back when. Seemingly, the early model had one size BB and the later, more common model had the other (I forget which way round it was but I think I had the latter, which is 73, and the earlier one was 68).
After my contact, they corrected the spec list, but the correct spec list is now lost since the frame isn't made ie dont trust any specs you find online as they won't necessarily be correct.
I quick google shows my memory was correct. Originally 68 but later 73. [url= http://singletrackmag.com/forum/topic/ragley-mmmbop-bb-axle-length ]Here[/url] and [url= http://www.mtb-news.de/forum/showthread.php?t=494986 ]here (german)[/url]
Yep. Definitely 73mm. I measured it before buying the crankset.
I will just switch the spacer to the other side and see how it goes.
Hopey I can get the drive side cup out. I thi k it was slightly cross threaded. It was a little difficult to get on!! Doh !
Yep. Bottom bracket threads are stuffed! Damn. Need to try get the internal BB thread chased at my LBS. and maybe need a new BB. Soo painful!!
Easiest way to tell what BB width you have is by measuring it with something.
Just checked mine. Its 73mm, one spacer on the drive side. No problems although like always on a triple, front mech needs careful positioning.
The problem has never been "what size bottom bracket do I have". A ruler answered that before I bought the new BB and crank.
It is a problem with the spacer being on the drive side. It seems to throw the front derailleur out and it won't adjust with the different chain line. I re adjusted the front mech from scratch but it just wouldn't change smoothly. Didn't like the large or granny front ring.
I have now put the spacer on the non drive side and everything is working perfectly.