2-Stroke Wiseco Break In

I'm getting ready to put in a Wiseco in my KDX220. I've heard different techniques for proper break-in: the steady-incrementally increase the load method and the hit-it-hard-right-off-the-bat method.

Which is gonna be better for a 2-stroke that's getting a Wiseco forged piston?

Ride it , Like you stole it....:mad:

I always warmed up the bike really good then shut her down, Wait until cool then repeat. Once cool again take a couple of easy laps then let it cool again. Then ride it like you stole it.

The "ride it hard" technique is for 4 strokes ONLY!!! They have an oil ring that needs to seat properly. A 2 stroke on the other hand, needs to be broken in EASY.

Ist ride of the day 1/4 throttle for 15 min let bike cool down-check bolts for tightness

2nd 1/2 throttle for 15-20 min let bike cool down-check bolts

3rd 3/4 for 15-20 let bike cool down-check bolts

4th -go nuts

I do this on both 2 and 4 stroke.

BTW-both type of engines need the rings to seat -it helps form better compression and rings wear more even keeping the cylinder bore round.:mad:

Ist ride of the day 1/4 throttle for 15 min let bike cool down-check bolts for tightness

2nd 1/2 throttle for 15-20 min let bike cool down-check bolts

3rd 3/4 for 15-20 let bike cool down-check bolts

4th -go nuts

I do this on both 2 and 4 stroke.

BTW-both type of engines need the rings to seat -it helps form better compression and rings wear more even keeping the cylinder bore round.:mad:

Can you tell when the rings seat? I've heard that it's noticeable.

You can't tell-I've broke in many engines and have never noticed a difference except when you go a bigger bore and you notice that right away. For whomever told you that ,it must have been phycological.

When breaking in a 2 stroke the most import part of the break in has nothing to do with the rings. it's actually the piston skirt. you hear the people talk about warm up let it cool several times. Well this is correct, however it is to work harden the lower portion of the piston skirt and form fit it to your cylinder. Under high RPM the skirt will flex, and more so when new and prior to work hardening. If over rev'd prior to break in, you can damage the piston, and cause metal blurring. have you ever pulled an engine down, and you see the piston skirt has blurred or torn metal. look at it with a strong magnifier, and you can see the damage. Low RPM's, not riding, just above idle until the engine is completely warm, let it cool completely, do this twice, then ride about 15 minutes without over revving. after that you are good to go.

Ist ride of the day 1/4 throttle for 15 min let bike cool down-check bolts for tightness

2nd 1/2 throttle for 15-20 min let bike cool down-check bolts

3rd 3/4 for 15-20 let bike cool down-check bolts

4th -go nuts

I do this on both 2 and 4 stroke.

BTW-both type of engines need the rings to seat -it helps form better compression and rings wear more even keeping the cylinder bore round.:mad:

This is a safe method.Also when ever you start the bike,warm it up slowly.I see so many guys start their bike cold and rev the piss out of it.to warm it up quickly.The engine heats at different rates,mainly the cylinder and the case.If you rev out the bike when its cold it's possible to get base gasket leaks.

I just got done doing the final break in cycle on my 200. Its amazing what a new top end can do for the feel of a bike.

I just got done doing the final break in cycle on my 200. Its amazing what a new top end can do for the feel of a bike.

What kind of break in did you use?

This is a safe method.Also when ever you start the bike,warm it up slowly.I see so many guys start their bike cold and rev the piss out of it.to warm it up quickly.The engine heats at different rates,mainly the cylinder and the case.If you rev out the bike when its cold it's possible to get base gasket leaks.

I'd agree with your comment about warm up. I've researched this break in topic a bit and found some interesting suggestions on Eric Gorr's site (one of the engine gurus for those who don't know). He goes as far as to suggest that when warming up use minimal RPMs by managing your choke.

Great stuff, guys. This is a "controversial" topic, but generally it seems like I should use at least a few "easy" cycles before business as usual.

What kind of break in did you use?

I did heat cycles with no load on the engine then took her out and ran it easy for about 20 mins. Make sure you let it cool down completely inbetween heat cycles (hour or so depending on the weather)

im trading my bike for a 125 and it has a new top end with a weisco piston. am i aloud to just start it up and see if it runs before i trade or will that mess up the engine if i dont break it in that day? thanks

im trading my bike for a 125 and it has a new top end with a weisco piston. am i aloud to just start it up and see if it runs before i trade or will that mess up the engine if i dont break it in that day? thanks

just start it up and see how it runs.:banghead:

yea it shouldnt hurt it right? because when you break it in you want it to be cool for the next cycle. itll be even better a week or so of cooling.

yea it shouldnt hurt it right? because when you break it in you want it to be cool for the next cycle. itll be even better a week or so of cooling.

lol yeah itll be fine.:banghead:

im trading my bike for a 125 and it has a new top end with a weisco piston. am i aloud to just start it up and see if it runs before i trade or will that mess up the engine if i dont break it in that day? thanks

Careful here. I bought a bike once that had a "new top end". The owner wouldn't let me run it hard and like a duma$$ I bought it anyway. First ride the motor blew, upon teardown it was obviously a very old piston.

I'd tell the owner that he needs to break it in before you buy it.

Heat cycle is what I used for my Wiseco top end. I remember reading something about their pistons being forged rather than cast? (stock) so the pistons need to be properly warmed up better.

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