JB Rear Rain Tires

[Brad Fish]

Is there a rear wheel width rule in JB? I had someone tell me that there was but I read through the rules a bunch of times and can't find anything.

I bought 2 sets of rains. One for my shifter and I was hoping to use the second on my son's JB kart.

It's a cadet with a Comer K-80 if that matters. It typically runs 4.5 wide on all 4 corners. With the rains on, it would have 4.5's up front and 6.5's in the rear.

Thanks,

[Alan Sheidler]

You should go ahead and bite the bullet and buy a second set of fronts for the rear of the cadet kart. Changing to the larger tire may well upset the handling of the kart, and would certainly require a re-gearing for wet days. If the bolt pattern is the same (You run hubs on the front of the cadet? Normally fronts for the FJ karts have the bearings in the wheel.) for both karts, I can see swapping out the fronts between your kart and and his, but not the rears.

And, 6 - 6.5 inches (150 - 170 mm) is a common width range for the shifter's rain tire rims... Rains will not work well on the 8" (200 - 210mm) dry tire rims. I forget whether the wheel itself is specified in FJ, or just the maximum tire size.

YMMV

[Scott Boito]

Yeah, definitely stay with the 4.5/4.6 all around, especially in the rain. Narrower in the rain is better.
_________________
KM #68 - Haase/Honda kart
BetterOffRacing
Member of the SCCA KAC

[Alan Sheidler]

Thinking about what I mentioned regarding the front wheel bearings... Unless you are running hubs on the front of the cadet, you could always run your front shifter rain wheels/tires on the rear of the cadet, and have dedicated wheels with bearings and rain tires for the front of the FJ.

My experience is that even if used several times, the front rains on a shifter last a long time, whereas the rear tread just seems to magically disappear.

[Brad Fish]

The cadet does have front hubs. Sharing is a great idea that I did not think of. Thanks!