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tri boy
10th June 2009, 15:47
Need a bit of help locating pistons and rings for the above bike, (ZXR250C?).
Happy to go oversize as the sleeves are not in the best shape, 48mm bore presently.
Have been checking out Wiseco, Moriwaki sites etc as I can;t locate genuine parts, but I havn't exhausted every option yet.
The young owner bought a lemon with 70psi in the pots and I'm hoping to get this job out of the workshop as a good runner, rather than the younun doing all his dough on a bike that don't go.
Thanks in advance;)

The Pastor
10th June 2009, 17:28
good luck mate, good luck.

can always get them made, but it aint very cheap!

tri boy
10th June 2009, 19:37
Yep, she's a struggle getting parts for them. I need to learn Japanese, and trawl their bike sites.
Got one engine from the wreckers on loan, (cheers Wayne at Bike Busters), and stripped the top end this arvo.
Damaged cylinder block, but the liners are good as well as the pistons n rings.
They measure 49mm, so I'll press the sleeves, and fit them to the old block, and get the blocked faced as well as the old head. (it's in good condition with good valves etc).
Gudgeon bores all match etc, so with a bit of luck the owner will be out thrashing his bike soon.

xwhatsit
10th June 2009, 20:47
The ZXR250A was 48x34.5mm, the C was 49x33.1mm. Why they made such a minor change for a bike they weren't even making a profit on...

But anyway, just some info -- could the original engine be an A (fitted in a C frame) and the wrecker's engine be a C? I suppose as long as the sleeves have the same outer dimensions then it won't matter... surely there's enough spare length at the bottom of the C sleeves to allow for the slightly longer stroke. He'll be getting a bit of extra capacity too (260.3 ccm :D).

tri boy
10th June 2009, 21:58
Thanks for the info xer. Possibly an engine swap had been carried out earlier in it's life. The OD of the dry liners is exactly the same, and tomorrow I'll check on the liner length.
Jobs like these are fun for the research angle, but really are time/money killers for workshops.
An hour lost travelling to the wreckers, another 1/2hr for drop offs/pickups to machinists etc. All of which rarely gets charged to owners.
Mechanics generally do the best they can for the young guys with f all money. But it is a bit of a drag.