rear tire size.

Thanks for having me. Im a new KZ owner..recently aquired a 76 KZ900, and im looking for 2 things..1) what is the Best/easiest upgrade for ignition from points to electronic? 2) What is the widest tire size I can put on rear stock wheel? Thanks for any advice..randy

You can fit a 130/90-18 tire on the stock wheel BUT it isn't a great idea to do so. I ran 130 tires on the rear of my bike for many years. Eventually I discovered that because the rim pinches in that wide tire it deforms the cross section of the tread. As a result, the 130 tire doesn't work any better than the 120/90-18 tire; in fact, maybe not as well as the 120, plus it's a pain in the butt to mount. Also, on my bike the 130 rubbed on the stock chain guard so I had to buy an aftermarket guard. The 130 does look good on there though. :laugh: Ed

For ignition upgrade, it is hard to beat the Dyna S. It will work fine with stock coils.

Hi yes both 650Ed and Gman are correct. 120/90 is the best fit, ride combination, no need to go larger and shouldn't go smaller. I've run Dyna S electronic ignition and Accel yellow coils for almost 30 years, no problems. I'm sure if you went with Dyna 3 ohm coils, they would be excellent as well. Welcome and good luck.
Joe

I recently found out that the Avon am26 and the bridgestone bt45 both still come in standard sizes. You can get a 3.25x19 and a 4.00x18 which are the prescribed sizes from the factory. Im gonna try them out next time i need tires.

I went with the 410 front and 510 rear 35 years ago. That's wen I ran the K81 and IRC rear. Later I went with the K181 and Chin Shin rear. When I put my bike back on the road two years ago, I had to go with different brands, one to save money, two because Chin Shin no longer males road tires for bikes, at least that's what I was told. They got sew'd and lost. I bought a 100/90-19 for the front and a Nang Kang for the back. It handled like SHT on my dirt road and was squirrely in the turns. I wore out that POS and went with the Tour Master 110/90 front and 130/90-18 in back. It holds the road, I'm confident in the turns but still I go though a rear tire in four months. The bike is my daily driver. I have a truck but the bike wins.
Steve