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Top end. Forged or Cast?

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So it is finally time to do a top end on my 08. I figure have over 300hrs so I guess its time!!! :) I ride/race this bike hard too, and really haven't done too much to the engine. I have replaced the Intakes for SS, but so far that's all. Last race in October this year I put a hole in clutch cover and ran it almost out of oil too. I did noticed before it was too late. So we fixed it up the next morning and I raced another 60km on Sunday and it's still going strong!

So what piston are most guys replacing with? Stock Kawi Cast, or an aftermarket forged one? And Why? If the factory one has been so good why go with a forged piston - cost wise it all seems relative. I was advised I should replace the timing chain as well, so I guess I'll do that.

While I would like to do all the work myself, I don't think I'll have the time these days with a young family and such, but I will take it all apart and just drop the engine off at a local shop. I have $200 labour gift cert' there so that will help too :lol: Ice racing season is just around the corner too so I'd like have it back together by January:ride: If I do it myself, there will always be something else that gets the way!

Anything else I should replace while its apart? After five years, I am also still running the stock clutch basket and friction disks, 3rd year with he z-start pro! The only Kawi parts I've had fail is the shift shaft, and the lousy design of the rear brake pedal - I keep bending or breaking the toe piece. Fork seals seem need replacing at least once a year too.

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I'm with ya. I've got a LOT of miles...well in excess of 15K. I replaced the valves with SS...and at the same time I replaced the piston/rings/timing chain. Did the seals when I replaced the springs, but they've never leaked.(knock on wood) I've broken a shift lever or two, and a brake lever tip, but everything else has held up.

When I bought this, I bought a whole new head, valves, cams etc because I dreaded the day it blew up. It hasn't. Cylinder looked great when it was apart. I run Rotella, the cheap stuff, and change it infrequently. Clutch is the original OEM, with a year and half of Rekluse. Amazed at the abuse I've put this thing through. I'd like to put a KX head and convert to EFI...since Kawi isn't doing it for us.

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We had an 08 oem piston crack on the "skirt" part of the piston. My motor guy told me he had seen this happen a few times with the 08 KX and KLX pistons. This year we ran a 2011 KX piston in 4 different bikes with no issues. All 4 bikes have had a lot of time put on them this year.

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So it is finally time to do a top end on my 08. I figure have over 300hrs so I guess its time!!! :banghead: I ride/race this bike hard too, and really haven't done too much to the engine. I have replaced the Intakes for SS, but so far that's all. Last race in October this year I put a hole in clutch cover and ran it almost out of oil too. I did noticed before it was too late. So we fixed it up the next morning and I raced another 60km on Sunday and it's still going strong!

So what piston are most guys replacing with? Stock Kawi Cast, or an aftermarket forged one? And Why? If the factory one has been so good why go with a forged piston - cost wise it all seems relative. I was advised I should replace the timing chain as well, so I guess I'll do that.

While I would like to do all the work myself, I don't think I'll have the time these days with a young family and such, but I will take it all apart and just drop the engine off at a local shop. I have $200 labour gift cert' there so that will help too :lol: Ice racing season is just around the corner too so I'd like have it back together by January:ride: If I do it myself, there will always be something else that gets the way!

Anything else I should replace while its apart? After five years, I am also still running the stock clutch basket and friction disks, 3rd year with he z-start pro! The only Kawi parts I've had fail is the shift shaft, and the lousy design of the rear brake pedal - I keep bending or breaking the toe piece. Fork seals seem need replacing at least once a year too.

For 4 stroke application go with the forged if you are using it for a high revving 2 stroke you need to go with the cast!!!!:)

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