k2 proflex evo 4

[timber 2114]

hi just finished building my k2 proflex evo 4, has any one come across the chain rubbing on swinging arm when its on the large cog at front and the two largest gogs on the rear , this is a 9 speed gog on rear any ideas would be greatful thanks.

[Colin]

I've got a 4000se which is essentially the same as an Evo 4.0 (I'm pretty certain) and no I don't get this problem, as it will in theory achieve all gear combinations, but Large to Large is deffo not a recommended "real world" gear option, too much lateral force on the chain and other components, so if this is the only problem then you could just live with it and don't use that gear combination(s)
But.......the cause could be the use of the wrong Bottom Bracket or a too large Big Ring......?
The original BB was a 73 x 113, with a Shimano Deore LX or XT, 22/32/42 teeth crankset.
but this could be different if you're using a different Crankset.

http://www.bikepedia.com/quickbike/BikeSpecs.aspx?year=2000&brand=K2&model=EVO+4.0

So, what have you got on it?

Col.

[timber 2114]

ok thanks i will have a look , had a quick look its a truvativ x flow on the front 22/32/42 and a sram 11 to 32 will have a better  look at weekend cheers dave.

[Spokes]

I had this problem with the OZ I just built. I first fitted an 11/34 rear cassette but the chain hit the swingarm. I swopped it for a 11/32 and it just clears by about 5mm. I think it's due to the Fox rear shock I'm using which is slightly longer than standard.  Front is 22/32/42 so in theory either cassette should have fitted as the OZm had a 12/34 cassette as standard so it must be due to the shock.
Have you changed out your rear shock?

Chris

[timber 2114]

no the rear is still a noleen nr2 i think will check that, going to have a look this weekend it had a 11/34 on when i got it and a race face crank but they were past there best, but it seemed ok with them on mybe i should have look closer before getting rid of them cheers

[Colin]

Sounds to me like a case of getting the right BB for the "new" crank to get the chainline correct as per original.

Still running the NR-4 on the Missus' OzX, but will aim to swap for an RP23 in the winter. and then see if anything changes........

Col.

[Spokes]

Hmm I'm running a XT Hollow tec 2. It's definitely spaced correctly for the frame as per instructions but I wonder if that is the reason? I'll try some measurements when I'm in the shed next.

Chris

[Colin]

Just checked on the OzX and to be honest the clearance on 46/34 combo is just about 1mm....!!
That's when the bike is unloaded, but if the RP23 is just slightly longer I can see it could cause issues if this gear combo was ever used (V. Unlikely!)
I knew all gears were achievable, but didn't check just how close it was!

Col.

[Spokes]

Yep that was my problem and under load you hear the nasty sound of chain against carbon. Like a saw!

Chris