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Technical & Reference Section => Tech and Restoration => Topic started by: motomagII on February 24, 2011, 08:47 PM

Title: chain lignment problem
Post by: motomagII on February 24, 2011, 08:47 PM

is there such thing to fit on rear wheel before the freewheel to space it oujt a bit i cant get my chain alligned correctly andf the cranks are at max i can change em /

Title: Re: chain lignment problem
Post by: HEYWOOD BMX on February 24, 2011, 08:50 PM

 :) Yes.Try the Hope bottom bracket spacers (1mm) from CRC,same dims as Shimano/freewheel hubs.Can be awkward as EX-type BBs are designed to be used with cassette hubs & MTB cranks have a different chainline to BMXs.

http://www.chainreactioncycles.com/Models.aspx'modelID=36416

Title: Re: chain lignment problem
Post by: motomagII on February 24, 2011, 08:55 PM

to be honest james its very very close .im about 1mm out maybe 1.5 from being happy with it even though it is rideable as is id like to get it tiny bit nearer centre of chain on ring

Title: Re: chain lignment problem
Post by: HEYWOOD BMX on February 24, 2011, 09:04 PM

Quote from: motomagII on February 24, 2011, 08:55 PM

to be honest james its very very close .im about 1mm out maybe 1.5 from being happy with it even though it is rideable as is id like to get it tiny bit nearer centre of chain on ring

 Try removing the 2.5mm spacer on the drive side of the BB & use 2 x1mm spacers instead & another 1mm spacer on the non-drive side.

Title: Re: chain lignment problem
Post by: motomagII on February 24, 2011, 09:07 PM

no spacers there kind of 2 waqshers at 1mm ther i took one out but the crank arm then rubbed on the bb shell .

Title: Re: chain lignment problem
Post by: HEYWOOD BMX on February 24, 2011, 09:32 PM

? Any pics? Normally there should be 2 x 2.5mm plastic BB spacers on the non-drive side and 1 x 2.5mm on the drive side.Also maybe 1 or 2 1mm axle washers between the ends of the BB bearing & the arms if needed.

Title: Re: chain lignment problem
Post by: Chinadog on February 25, 2011, 02:26 PM

You used to get a freewheel spacer with some brands of power disk bitd, the ones where the chainring bolts to the outside face.

Maybe try a decent old type bike shop :-\

Title: Re: chain lignment problem
Post by: john4130 on February 25, 2011, 05:19 PM

you could try a thinner cone locknut on the freewheel side.

Title: Re: chain lignment problem
Post by: Bigplinky on February 25, 2011, 05:31 PM

You tried running a powerdisc with the chainwheel on the inside Greg?

Title: Re: chain lignment problem
Post by: motomagII on February 25, 2011, 05:38 PM

Quote from: Bigplinky on February 25, 2011, 05:31 PM

You tried running a powerdisc with the chainwheel on the inside Greg?

they are 4 arm alloy shimano craqnks so only use a chainring as spider if fixed
 :daumenhoch: