Frame question

[minnsy]

Mate has a Kona Bear - 21 inch frame... (he's a big guy!) he has found a 19inch frame (chain and seat stays not included) at a knockdown price via one of the online retailers...and he was wondering if the seat and chain stays from his 21 inch would be the right length for the 19inch frame, and not upset the geometry much. He would be carrying over his current front and rear suspension, and all running gear etc...

The move to the 19inch frame is to make the bike a little more 'wieldy' when singletracking..

Have tried searching, but no answers on this so far... Any ideas?

Cheers

Dave

 

[dan_bo]

nothing wrong with trying is there?

 

[dan_bo]

just don't expect the warranty to stick!

 

[02GF74]

removebale chain and seat stays - that'll be full suspension frame.

take a peek at CoilAir Supreme

and look at chain stays length. these are 17.5 in for all frame sizes.

and this is pretty much standard on all frames I have looked out so that one is the same.

I have never seen the seat stay length given in any frame spec. and for a rigid frame this would be different for each frame.

on full suspension frames the manufacturer has the option of making different seat stays or different link (the part that pivots). from my experience looking at at specialized epic bike, the pivot is at different point on seat tube meaning that the same pivot and seat tube can be used. One would think that is the logical way to do it and I would expect Kona to do that.

Note that in that link, the seat tube angle is the same therfore the rear triangle geometry can be made the same for the same legth tube but locate the pivot point. that would be logical too.

therefore I would expect the rear end to be compatible across the frame sizes.

pop an email to Kona I guess to confirm.

 

[minnsy]

Frame

Thanks for the info, and indeed, that link says it all really...

Cheers

Dave

 

[barq]

A couple of years ago I cracked one of the welds on my Kona Kikapu. The UK distributor, Paligap, replaced the chainstay without knowing the frame size. That seems to support the idea that Kona use a one-size-fits-all rear-triangle.