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Technical & Reference Section => Tech and Restoration => Topic started by: mattuk on February 20, 2011, 11:44 AM

Title: 3 piece crank spacer US BB question
Post by: mattuk on February 20, 2011, 11:44 AM

ot a haro fusion 3 piece crank withe the axle bearings and bolts etc for a US BB but it missng the centre spacer tube thing.  will it work fine without this or do i have ti have one for it to work right

i cant get my head round what it actually does TBH   i cant see how it wont function fine without it

any thoughts?

Title: Re: 3 piece crank spacer US BB question
Post by: Betty on February 20, 2011, 11:55 AM

If your cranks have pinch bolts like redline flights you dont need it, tighten the axle bolts enough so there's no play then tighten the pinch bolts up tight, then tighten the spindle bolts proper

If your cranks have no pinch bolts and tighten using just the spindle bolts like profiles you'll need it, tightening the spindle bolts will squash the BB bearings together and the cranks wont spin freely

Title: Re: 3 piece crank spacer US BB question
Post by: mattuk on February 20, 2011, 12:11 PM

ah right i get ya! thanks mate     mine have the pinch bolts on the arms so all is well  :D

Title: Re: 3 piece crank spacer US BB question
Post by: Munnyella on February 20, 2011, 06:36 PM

I have a 19mm spacer if you need it

Title: Re: 3 piece crank spacer US BB question
Post by: Jon The Bassist on February 20, 2011, 06:52 PM

I'd use a spacer to support the bearings from the inside against any sideways forces when cranking  :daumenhoch:

Title: Re: 3 piece crank spacer US BB question
Post by: mattuk on February 20, 2011, 10:32 PM

should be ok matey but cheers for the offer its only going on a bike thats for "show" and never gets ridden just sits in the garage doing nothing except looking pretty  :P