KZ650 Tire and Tubes

My son has a KZ650 completely rebuilt with Lester rims.

The other day I noticed small cracks in his rear tire. The tires arent old - they are Avon Road Riders, but they look dry rotted.

He went ahead and bought tubeless Shinko 712 tires, 100/90/19 in the front and 110/90/18 in the rear.

We havent looked at the bike yet, but would those Lester rims need a tube or can we just put on the tubeless Shinko?

Thank you gentlemen.

Its my understanding that 1st gen Lester's required tubes, later models are tubeless. The rims should be marked with an TL if there tubeless. If at all In doubt run tubes. You can run tubes in tubeless tires.

Blue58 wrote: Its my understanding that 1st gen Lester's required tubes, later models are tubeless. The rims should be marked with an TL if there tubeless. If at all In doubt run tubes. You can run tubes in tubeless tires.

Thank you for letting me know.

Im not sure what year the lesters are. I also searched the forum and discovered that a 120/90/18 in the rear is better than 1 110/90/18.

I run the 130/90-18 Shinkos on mine. 110/90-19 front. Great tires. The tour master tires have a hard rubber stripe down the center for better milage. Just over 5000 miles on the rear even with my lead wrist. :woohoo:
Steve
www.chapmoto.com/shinko-230-tour-master-...re-parent-369-874160
www.chapmoto.com/shinko-230-tour-master-...re-parent-369-874170

SWest wrote: I run the 130/90-18 Shinkos on mine. 110/90-19 front. Great tires. The tour master tires have a hard rubber stripe down the center for better milage. Just over 5000 miles on the rear even with my lead wrist. :woohoo:
Steve
www.chapmoto.com/shinko-230-tour-master-...re-parent-369-874160
www.chapmoto.com/shinko-230-tour-master-...re-parent-369-874170

I actually searched the forum and saw an old post by you where you said 130/90/18 rubbed on the chain guard. My son has no chain guard on the bike, but I also know the wider you go or bigger you go, the less responsive the bike can be.

My son is going to return the rear Shinko 712 110/90/18 for a 120/90/18 and this time he can order the inner tubes, which he forgot. We both though the Lesters would not need inner tubes.

In the meantime hes going to spray the tires on the bike with brake fluid so they soften a bit. I think they are UV damaged.

Please don't spray the tires with brake fluid. That's just plain silly and may do damage.

Avon Roadriders are great tires but they are prone to superficial sidewall cracking. I've never heard of one outright failing but I don't blame you guys for wanting to replace them. I suggest contacting Avon and voicing your experiences. Avon has replaced a lot of those tires under warranty so it's worth a try.

As far as the width of the tire to use is concern there are two factors that come into play: the width of the rim and clearance on the bike. You can run a 120 on a 2.15" wheel but it's a little beyond the customary recommendation. I wouldn't go with a 130 on a rim that narrow even if there is clearance.

110/90-18 is too narrow for the rear of a KZ650.

For many years I ran 130/90-18 on the rear of mine, but eventually I learned it did not offer any advantage over the 120/90-18 tire. The 130 was difficult to mount and I could not use the stock chain guard without the tire rubbing. Also, squeezing that tire onto the stock rim deformed the shape of the tire so It did not have any larger contact path than the 120/90-18 tire. I switched to 120/90-18 and will never use the 130 size again. Also, I use tubes and rim locks. Ed

I ran the 120 last year and got the same if not less mileage out of it. Didn't notice any difference in handling. Gonna buy another one in a few days.
Steve

Kinda off topic a bit. Those Lester's are pretty rare items ,worth a bit and very cool in my humble opinion.

Blue58 wrote: Kinda off topic a bit. Those Lester's are pretty rare items ,worth a bit and very cool in my humble opinion.

Thanks. I think they are much better than spoke rims.

650ed wrote: 110/90-18 is too narrow for the rear of a KZ650.

For many years I ran 130/90-18 on the rear of mine, but eventually I learned it did not offer any advantage over the 120/90-18 tire. The 130 was difficult to mount and I could not use the stock chain guard without the tire rubbing. Also, squeezing that tire onto the stock rim deformed the shape of the tire so It did not have any larger contact path than the 120/90-18 tire. I switched to 120/90-18 and will never use the 130 size again. Also, I use tubes and rim locks. Ed

Ed, just wondering why do think 110's are too narrow? The stock rear tires were 4" wide. 110's are 110 mm wide, which is over 4.25". I have run 4" x 18 , 120 , and right now 110 . They all fit and handled fine to me.

Kent

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