Rear tire shredding :(

Hello everyone,
I'm new to the forum, new to my KZ650, and new to motorcycles. Just working my way through the whole thing. So far I'm loving riding, and loving the bike, but I have had a few issues so far.... The most serious being that my rear tire seams to be getting shredded in two spots, and it seems that I can bottom the suspension out over rough bumps.

It looks like the pre-load on the shocks is at its highest setting, but beyond that i have no idea how to stop the rubbing. Is there a bump stop thats supposed to be there or is it time for new shocks/springs?

Other that the rubbing the electric start doesn't work, the horn button doesn't work when the turn signal arm/bracket is sitting inside the housing (wtf on that one) and I seem to have a charging problem (I think). But I'm not as worried about these issues.

If your KZ650 has the original shocks they are long overdue for replacement. The originals on mine only lasted a couple years; about 10 - 12k miles before I was pogo-ing in fast corners. Got any pics of your bike? Ed

ebouwman wrote: ...KZ650...rear tire seams to be getting shredded in two spots, and it seems that I can bottom the suspension out over rough bumps.
It looks like the pre-load on the shocks is at its highest setting, but beyond that i have no idea how to stop the rubbing. Is there a bump stop thats supposed to be there or is it time for new shocks/springs?....

Hello, ebouwman, and WELCOME to KZrider!

Perhaps a previous owner "lowered" the seat height by replacing the stock shocks with shorter shocks from some other model.

The stock shocks should bottom out before any hard parts hit the rear tire.

Good Fortune!

650ed wrote: If your KZ650 has the original shocks they are long overdue for replacement. The originals on mine only lasted a couple years; about 10 - 12k miles before I was pogo-ing in fast corners. Got any pics of your bike? Ed

Ya it was kind of pogo-ing a bit...

So where would i get new shocks? An auto parts store?

Heres a picture anyways.

Shocks and Suspensions
www.progressivesuspension.com
www.racetech.com
www.hygearsuspension.com
www.aftershocks-suspension.com
www.gpsuspension.com
www.ikonsuspension.com/content/the_ikon_suspension_story.shtml (The former Koni shock absorbers)
www.davequinnmotorcycles.com/cgi-bin/web...GON_TWIN_SHOCKS.html
mpcustomvalve.co.za/index.html

No,you'll need to purchase new shocks from suppliers like above.

Highly recommend Z1 Enterprises for 90% of your parts

Thanks guys,
I've had Z1 come up in google searches, but its nice to know it's considered a reputable dealer.

I did buy an onboard trickle charger and put that in today to help with the battery drain while sitting, at some point I'll change out the voltage regulator, probably when I get to the shocks.

Z1E is more than reputable! It's a must!

Les

I looked into changing the rear tires when i realized that it has a 130/90 on the rear. I guess its supposed to be a 110/90 on the rear... so that roughly means that i've been getting 1.8cm less clearance than a 110 tire gives. That combined with the bikes old suspension and my fat ass, and viola, tires munched.

I also kind of moved the rear fender/s around so that they slide above that center fender mount so i get another bit of clearance, and so there are no bolts for the tire to rub on.

ebouwman wrote: I looked into changing the rear tires when i realized that it has a 130/90 on the rear. I guess its supposed to be a 110/90 on the rear... so that roughly means that i've been getting 1.8cm less clearance than a 110 tire gives. That combined with the bikes old suspension and my fat ass, and viola, tires munched.

I also kind of moved the rear fender/s around so that they slide above that center fender mount so i get another bit of clearance, and so there are no bolts for the tire to rub on.

That is NOT the correct tire size for a KZ650. Judging by your picture (please add your bike's year/model to your signature so we don't need to search for this info) you own a KZ650-B. Assuming this is true, if you are buying a metric size tire it should have a 120/90-18 tire on the rear. In fact, the 130/90-18 (while not the recommended size) should have worked ok and should not have rubbed the fender. I know because I ran tires in that size on my bike for about 20 years. I may be wrong, but I suspect those replacement shocks on your bike are not correct for it and are allowing the rear to drop down too low when you hit bumps which in turn caused the tire and fender to kiss. I would replace both tires (as a matched set) and the shocks. Just make sure you do adequate research (this site works great) to ensure you get the correct items. Ed

Welcome ebouwman.
Nice 650 you've found there.


I've also ran a 130 rear tire for years, but went to a 120 last time around and find the 120 to be best.