Wider rim with stock swingarm

Can anyone tell me if it's ok to lace a 18" 4.25 wide rim on the stock hub and run that with the original swing arm? I plan to mount a 140mm tire on that. If anyone has tried this and knows the limits of this modification I would be thrilled to know BEFORE I buy a rim and trial and error it.

I have run a 3.50 rim with a 130 tire on my 750 h2b and the chain came really close to the tire. I plan to use the same combo with my "new" 78 kz1000. The 78 kz currently has a 130 tire on a Lester mag and there appears to be about 1/2" clearance between the chain and the tire. I don't know about going to bigger 4.25 wheel and a 140 tire on the stock swingarm, but after a quick glance it looks do-able. My guess is, at worst, you might have to offset the countershaft sprocket a little to allow the chain to clear the side of the tire.

On my 77kz1000, I have a wider aftermarket 'arm and run a zx6r wheel with a 180 tire and no issues with a 5/8" offset countershaft sprocket.

Hopefully someone out there has tried your proposed set up!

How can you offset one sprocket and not another? Wouldn't that create wear/alignment issues?

A wider rim won't move the rear sprocket further out if it's using the stock arm/hub/etc.

DoubleDub wrote: How can you offset one sprocket and not another? Wouldn't that create wear/alignment issues?

A wider rim won't move the rear sprocket further out if it's using the stock arm/hub/etc.

+1 If you offset one sprocket you need to offset both sprockets.

Drooz is running a ZX6R wheel. That's a cast one, so the hub and wheel are one and in this case offset from the factory wheel, therefore necessitating an offset counter shaft sprocket.

TexasKZ wrote: Drooz is running a ZX6R wheel. That's a cast one, so the hub and wheel are one and in this case offset from the factory wheel, therefore necessitating an offset counter shaft sprocket.

I understood that - he was suggesting offsetting the front sprocket with the 4.25" rim from how I read his post.

I have a 18 x 3.50 spoke on mine with a 150 tire. If I went any bigger I might have chain/sproket probs

The 4.25 rim on a stock hub wouldn't be a problem. It's the tire that may cause some problems. I know a 130mm fits with clearance and have known some to run a 140mm tire. Some had no problems while others had interference problems. Tire profile makes a difference here...some will fit while others might not.

If you can find the spec's on the tires you can see which ones have a taller, rounder profile and which have a flatter profile. Also that 4.25 rim will flatten out a 140mm tire more then a 3.5 rim will so it will make a 140 tire basically wider.

DoubleDub wrote:
he was suggesting offsetting the front sprocket with the 4.25" rim from how I read his post.

Quite right "DoubleDub". Thank you for the clarification. The sprockets must be aligned properly to avoid binding and wear.

Thank you for addressing my question about rim width and tire size. I am going to try the 4.25. We have measured available room on each side and it seems like it should work and by the sounds of your experience, it also seems to be possible. I do not plan to change sprockets or offset them. Thanks again.