Broken piston!

Piston #1 had been soaking in gas/seafoam mix, and I was scrubbing with a brush trying to remove the carbon build-up. Suddenly part came flying off! Obviously this piston is junk, but now I'm wondering about the others. Should I now consider the other three suspect, and just replace all four?

Anyone know of a good source for pistons?

Used pistons are fairly cheap (usually because they are not replaced as they should last much longer than yours:laugh: :laugh: :laugh: ) and they will appear on eBay...replace all, if the opportunity arises:)

LeeLewis7 wrote:

Piston #1 had been soaking in gas/seafoam mix, and I was scrubbing with a brush trying to remove the carbon build-up. Suddenly part came flying off! Obviously this piston is junk, but now I'm wondering about the others. Should I now consider the other three suspect, and just replace all four?

YES!

I've got a set of 4 pistons(and rings)that I pulled out of my bike(77 KZ1000)when I went with my 1105's.
U2U me if you're interested,and if they'll work in your "P" model.

Thanks, Sandy. I don't know about fit, so I'd have to look into that. I guess the next step is to have my local dealer determine if the cylinders are still in spec. If they're not then it'll be time to bore.

I think the 77 pistons in your P model will give you about a 7:1 compression ratio (although I'm not sure, it gets confusing switching parts between the 998 and 1015 motors). There's a page at APE that explains the differences between the two motors.

(Shameless plug):

There are 1105 pistons, 1100 block, and GPz1100 cams for sale in the classifieds that will fit your motor

I don't think the earlier style pistons will fit the J motor. Buy Elliot's pistons, block and cams. The deal is when you buy a set of used pistons; always better to buy the matching block as the clearance between pistons and bore is critical and if you stick in used pistons into a cylinder they didn't come out of, they may or may not fit correctly.

(Apologies to all if the pics are messing up your view like they are mine. Don't know what happened. The thread looked fine yesterday.)

Well, the GPZ stuff sounds great, but I couldn't find it in the classifieds. You did mean the KZRider section?

If I understand the APE info correctly (thanks for that, BTW), the 81-82 GPZ stuff is a straight bolt-on fit for any J motor? Not really looking to hot-rod this particular bike, but in-spec bolt-on replacements sound good. Except for a couple of transmission bearings, the lower end seems to be fine.

Hmm, either it was an old ad and it timed out, or I posted it elsewhere and forgot to post it here

I'll PM you the details.

You're losin it,Steve.:laugh:

Heat gettin to ya?:blink: