KZ650 Tire and Tubes

650ed wrote: I guess a 110 will work, but given the 2.15 width of the stock KZ650 rear rim the 120 is also a correct fit (see image below). Either size may be appropriate, but I prefer the wider of the two. Ed

Thank you Ed. This is helpful

The 120 / 90 / 18 Shinko 712 arrived today. Bike Bandit is allowing us to return the smaller tire. I road my son's KZ650 with the very slightly dry rotted Avon Road Rider and it was a very bumpy ride. At first I thought it was the shock, the rubber seems very hard.

The front Avon on the bike seems to be fine. We have a new front and back shinko for my son's bike, but we are thinking of just changing the rear. What is your take on this? Is it ok to mix and match?

There shouldn't be a problem with the Shinko on the rear.
Steve

I have raced mixing brands. A lot of people will pupu it. Ideally you would want the same tire manufacturer front and rear because of the different sidewall and compound difference between brands and that effects how each tire behaves. But in most street applications it's not going to effect anything dramatically. Honestly you are feeling the suspension setup more then the tire at street speeds. If both tires are showing cracks I would replace both and start fresh. On the other side I have ridden street bikes with cracks in the tires and never had an issue. Then again being older and wiser I would not do it again.

WarrensKZ wrote: .......... I road my son's KZ650 with the very slightly dry rotted Avon Road Rider and it was a very bumpy ride. At first I thought it was the shock, the rubber seems very hard. ............

If your son's KZ650 still has the original rear shocks they probably are contributing to the ride problems. The original shocks on my KZ650 were shot before I had put 10,000 miles on it ( about 2 years). I then installed S&W shocks and they were great. Since 2007 I've been using Hagon shocks (see image below). They look similar to stock but work FAR better; they still work and look like new after about 20,000 miles. I really like them a lot! Ed

Think his boy has RFI shocks which are known to have stiff springs.
Road riders have a supple casing.

650ed wrote:

WarrensKZ wrote: .......... I road my son's KZ650 with the very slightly dry rotted Avon Road Rider and it was a very bumpy ride. At first I thought it was the shock, the rubber seems very hard. ............

If your son's KZ650 still has the original rear shocks they probably are contributing to the ride problems. The original shocks on my KZ650 were shot before I had put 10,000 miles on it ( about 2 years). I then installed S&W shocks and they were great. Since 2007 I've been using Hagon shocks (see image below). They look similar to stock but work FAR better; they still work and look like new after about 20,000 miles. I really like them a lot! Ed

We have bought another KZ an will be doing a mild cafe to it. I dont want to change my bike as its mostly original. so we now have another to play with. I will be purchasing these shocks as they match our color scheme idea

I am going to be replacing the rear wheel on my 76 KZ -
Its currently on a 16" rim and have 130/90 Dunlop tire. I have a 2.15 18" rim and spoke set but I am concerned about the width tire I can mount safely on the stock width rim.
I'd like to mount at least a 120 on the rear and per the chart 2.15 - 2.75 are acceptable but having spoken to the tire shop they are not comfortable with that combination.
Any issues mounting a 120 on a 2.15 rim out there?
There seem to may more options for tires on a 17" rim and wondering if a 17" rim with a spoke set for 18" rim will work?
I got the 2.15 18" rim for a bargain but I see the 2.75 rims run about $200-$300.
Any suggestions or recommendations based on your fitment?
Thanks - Greg

2.15 is narrow for a 120 tire but Kawasaki fitted them stock to a lot of KZ's so I think you are okay. Just don't go for anything more low profile than a 90 section.

I use a 120/90 V 18 on the rear of my 1977 KZ650-C1. It works very well. In the past I used a 130, but eventually I figured out that the narrow rim somewhat deforms the shape of the 130 leaving no more rubber on the ground than the 120. Plus the 130 was harder to mount of the rim. I'll never go back to the 130. Ed

Have always ran 120/90/18 also and love the fit. When I was younger and had dreams of a 810 kit I always planned on a 3 inch alum rim to get more tire. On the track or strip you'd need to spend the cash but not for everyday use.

Nessism wrote: 2.15 is narrow for a 120 tire but Kawasaki fitted them stock to a lot of KZ's so I think you are okay. Just don't go for anything more low profile than a 90 section.

Thanks - the 90 sidewall is so that it doesn't have bend around to the rim bead as much? - thanks for that -

KZB2 650 wrote: Have always ran 120/90/18 also and love the fit. When I was younger and had dreams of a 810 kit I always planned on a 3 inch alum rim to get more tire. On the track or strip you'd need to spend the cash but not for everyday use.

You ran the 120/90 on the stock (2.15) rim?