Kawasaki Sportsbike Riders Club - Australia - Online Forum

A couple of mates of mine have warned me about Wiseco pistons- apprently they are prone to seizure. One of these guys is a Kawasaki guru mechanic. I wonder if they are even half right? Whaddya reckon? (My DT200r has a Wiseco fitted- the second one apparently coz the first one lost the pin that locates the rings... )

they are as good as (a) the mechanic who fitted them in the first place (correct clearances etc), and (b) the owner of the bike they are in (correct oil, oil changes, correct jetting etc).

Wiseco did have a bit of a reputation in the late 70's/early 80's for seizing, but I have used them in both 2 and 4 stroke rebuilds over 20 years since then, and as long as you get the important bits correct, they are as good as anything else going around. The quality of the alloy used these days is better than what was available in the 70's.

Its pretty hard to source aftermarket pistons from anyone else *but* Wiseco anyway, sometimes there are odd piston kits on e-bay (like a set of Hi-comp Yoshi pistons for a Z900 ! missed out on those babies ).

I've run Wiseco Pistons in several two strokes without issue. hte piston in the KDX200 was Wiseco. It was still fine when I serviced the top end after four seasons and I re-used it with new rings!! That's how well it wore. I have also used one in my young fellas KX60 which became a 65 and the 80 which became an 85! No issues at all. As gos says, as long as you don't have other issues with the bike, and they are set up correctly to the correct tolerance running the correct mixture...no issues! but, if the bike had nipped a piston in the past, I would be looking for a crankcase air leak somewhere! This is the only issue I have ever had with two smokers of that era! Take it for a run and do a plug chop. (4th gear WFO..hit the kill switch. Pull plug and read it.) If it is jetted correctly with the correct oil ratio and it's still running dry, then a leak is happening somewhere. Check the carb manifolds first then look for other more time consuming leaks! Welcome to old two strokes!

I have heard about the Wiseco issue , but only the hersay . The trouble with a rumour getting round is always the doubt about that costly rebuild going bang though no fault of your own .
For a forged piston Woesner make plenty and Prox and Mikata also have available stuff . You might even find OEM stuff from a dealer .