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Technical & Reference Section => Tech and Restoration => Topic started by: magna13 on August 29, 2009, 12:40 AM

Title: sprocket help
Post by: magna13 on August 29, 2009, 12:40 AM
but a brand new sprocket on my crank but when i spin it round its all wonky :idiot2: whats happened help please?
Title: Re: sprocket help
Post by: HEYWOOD BMX on August 29, 2009, 01:03 AM
 :) Do you need/have a tophat washer on it? Have you bolted it to the crank arm?
Title: Re: sprocket help
Post by: magna13 on August 29, 2009, 01:36 AM
Yehh i will probibly need one, do i need it on the bolt that screws into the arm that keeps the sprocket on? cus at the moment im using two random washers i found ::) ::)
Title: Re: sprocket help
Post by: pickle on August 29, 2009, 08:31 AM
The sprocket shouldn't need washers on the bolt that holds it Zak.....it should sit flush against the crank arm.
The only washer you might need is the top hat one for the 19mm axle

Does that make sense mate?
Title: Re: sprocket help
Post by: moley on August 29, 2009, 09:16 AM
What Sprocket is it?

They usually have a recessed groove where the bolt screws to the crank arm to keep it more flush.

Your top hat needs to be tight too.  If it goes in and out by hand then it'll be crap.   

The top hats for the Profile sprockets are really tight and need twatting!!

I'd check it by eye when it spins. 

Some Cranks cause the sprocket to spin out of alignment when the crank arm bolt is too tight.  So tighten up your cranks first and then check the spin and then tighten the crank arm bolt.  If it spins true when loose but it pulls out of alignment when tight then maybe a small thin washer between the crank arm and sprocket might allow you to tighten it up fully while still keeping it true.     I'd only worry about it once you've fitted everything and checked it with a tensioned chain in place.   Some of the mid 90's GT/Profile sprockets are like this!!  a lot of OS Sprockets have a slight side to side wobble!!  :(
Title: Re: sprocket help
Post by: magna13 on August 29, 2009, 11:33 AM
The sprocket shouldn't need washers on the bolt that holds it Zak.....it should sit flush against the crank arm.
The only washer you might need is the top hat one for the 19mm axle

Does that make sense mate?

So it does not need washer's? ohh dear. well needed something there becasue on the DMR Crisis crank, you have an adapter so it can fit on to the spindle flush. the Chainwhel i have is a KinkBikeCo. one that comes on their completes. Compared to my DK 33t sprocket its really thin, when i put the adapter in the DK one, no adapter was showing, and fitted all within the chainring, i put the adapter on the Kink one and there is loads of the adapter showing, when i go to tighten this down to the crank arm, the adapter goes against the arm (as normal) but then when you go to screw the sprocket on theres a huge gap! hence the washers ??? can i get just any top hat washer from a bike shop?
Title: Re: sprocket help
Post by: magna13 on August 29, 2009, 11:33 AM
plus will it be ok to ride it as i wanna ride it today? ???
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