04 summit X 800, when to rebuild the top end??

[Summitstef]

I am in the process of cleaning up a '04 summit 800 for my brother. I already replaced the carb boots, chaincase seals and tightened up the y pipe bolts. The sled has 2000kms (1200 miles) on it. I was reading a past thread that the top end should be rebuilt, or is it okay to just redo the rings only? I have torn the top end down once on an 800 H.0 in a ZX and it was no picnic. I can only imagine how much fun it would be to do it on a REV!!??

 

[jrddillon]

I am in the process of cleaning up a '04 summit 800 for my brother. I already replaced the carb boots, chaincase seals and tightened up the y pipe bolts. The sled has 2000kms (1200 miles) on it. I was reading a past thread that the top end should be rebuilt, or is it okay to just redo the rings only? I have torn the top end down once on an 800 H.0 in a ZX and it was no picnic. I can only imagine how much fun it would be to do it on a REV!!??

my 04 blew 1 week after I sold it 2400mi.

 

[Blu Du]

its the ring locating pin that come out of the piston on mine and the ring spun and caught exhaust valve port . it took 3 hrs to rebuild top end in the motel parking lot in west. i had 3600 miles on mine.

 

[jscanga]

Just bought a '04 800 HO with 1600 miles and had the same question. Are the rings weak in this engine similar to the '03 800 and need replaced with a double ring aftermarket top end?

 

[pinnedunderdoo#3]

people have their own opinions on the double ring from wiseco..... but seems like after they put the wisecos in it never pulls the same again so im not a huge fan of them....

 

[rkbrkr]

rings

i beleive the ring issue lasted through 05, i did mine (rings only) at 1300 and its like night and day. big difference. all my buddys did there's at 700 to 800 i wish i would of sooner!

 

[Van Zee]

most 04 rings flaked apart. Mine had 1600 miles on it when i took it in under warranty. Still ran descent but new they needed changed and found out they had pretty much taken out the whole top end. I did not know it was any other year though. Ran with 03s and 05s quite a bit and havent heard anything.

 

[portgrinder]

there is 2 issues with the rings on these engines:

-They flake. Not a big deal, just lose some power

-The ring locator pins do not last. Anything past 2000 miles is a gamble. Once they wear out your rings are free to spin around until the end catches a port. Then its all over.....

 

[JKP]

The other item on these engines is the crank. After 3500 or so miles the Isoflex grease dries out and it is pretty much time for a crank. so if you are doing a complete top end it is well worth yanking the engine and doing it right.

 

[decarls]

a lot cheaper to do it now rather than wait till it starts to rattle then lock up. do the pistons and rings.

 

[jscanga]

What are thoughts on the "best" replacement pistons and rings?

 

[hymark860]

there is 2 issues with the rings on these engines:

-They flake. Not a big deal, just lose some power

-The ring locator pins do not last. Anything past 2000 miles is a gamble. Once they wear out your rings are free to spin around until the end catches a port. Then its all over.....

Happened to a friends 03.5 summit on the pto side less the 2k miles. tore it down to the crank and found mag seal was bad. grease was all over stator and flywheel.