When to rebuild top end??

8 replies to this topic
  • Yak

Posted June 17, 2002 - 10:10 AM


I remember the 2 stroke crowd should rebuild their top end ever ~80-90 hours. How often do you rebuild a 426 top end?

  • yznvegas

Posted June 17, 2002 - 10:36 AM


I don't know of any 2-stroke that will last 80-90 hours before a top end that is crazy. Maybe like 10-20 hours depending on how you ride.

  • thumper4life

Posted June 17, 2002 - 11:10 AM


once a year

  • motoman393

Posted June 17, 2002 - 12:55 PM


Im still on the stock top end and I bought the bike Nov. 15 00'. I will replace the piston, rings, cam chain, cam sprockets and crank fairly soon...so when my Dad gets my bike in 2 months it will be "fresh". Im glad I changed my oil every 1-2 rides. Some of the people I ride with have already had to replace their top ends due to lack of maintainence (like changing the oil/air filter). Later,


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  • Striker

Posted June 17, 2002 - 02:23 PM


I know this may sound stupid...but, when you say "change" your oil, do you just drain it and replace it... or do you change the filter every time as well?

  • Shawn_Mc

Posted June 17, 2002 - 02:30 PM


I usually do the top end when the connecting rod is poking out the front of the cylinder. Ive learned that this is also a great time to change the oil. But this whole nonsense of changing spark plugs is out of control. Im still using the same plug out of my XR75 from 1976. I just made an adapter and pounded it right into the head on my 426 works great! Boy Ill tell what else is over rated, chain lube! Useless! Just take some drippings from the ole bacon and egg breakfast and smear it on there and wah law, its all nice and greazy. Add benefit there is the appetite gets all worked up from the smell of cooking bacon when the chain gets nice and hot. Martha Stewart aint go nuthin on me! :)

  • therapture

Posted June 17, 2002 - 02:41 PM


I only changed mine due to leaving the oil drain plug LOOSE...and 10 minutes into a ride it went *poof* *clatter clatter* :)

So a new cylinder, piston, rings, gaskets was all it took because I shut it DOWN as soon as I heard something funny. Even the cams were not scored!!!

LOL...take it easy on me guys!

  • Guest_mxrider426_*

Posted June 17, 2002 - 04:37 PM


Ouch!! :)

  • Shawn_Mc

Posted June 18, 2002 - 02:18 PM


therapture, didnt it leak!!?? Youd think a loose drain plug would leak. Unless it was really loose enough to leak but loose enough to vibrate out. That would suck large!

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