break in

[madmike90]

whats the best break in procedure for a 2 stroke after doing a top end rebuild?

1996 cr125
-brand new replated cylinder
-new Namura piston with teflon coatings on the skirt
-new ring of course gapped to (.018") in the cylinder.

i drained and flushed the crankcase so what oil should i be running in there now?

and what break in procedure?

thanks!
mike

 

[noj]

hi mike just run the bike around using no more than half throttle on 1 full tank of fuel then she shud be gud to go!

 

[RM85rider123]

there are many, many ways (and opinions) to do a break-in. Noj's procedure can work, but you can always use the search feature up top and search for more procedures. For the oil, you can use Bel-ray gear saver 80W for about $10-11, But that is just my opinion.

 

[Moparman1539]

I just rebuilt my motor on my YZ250. I just started it up, and let it idle for like 10min or so, (like to running temps) then shut it off and let it sit for about 2 hours until it was Completely cooled down and do it again, and let it completely cool down. then just putt around on it for awhile, never going past half throttle for almost a full tank. Then started to ride it like a normally would... well working up to it in little steps. Motor is still working and going strong... Thats what a couple people told to me to do atleast, and seemed to work good.

 

[brentn]

^sounds like good advice.

For my stihl 2 stroke saw, it recommended the same thing in the manual, to run it at idle for about 10-15 minutes before using for the first time.

I'm pretty sure the only reason for break in is to allow the rings to properly wear into the cylinder to provide the best seal. For a new piston, cylinder and rings, I don't think it's a big big deal. But on a honed/used cylinder it could help. Aggressively running the engine right after a fresh rebuild 'could' cause the rings to form poorly to the clinder resulting in less longevity.

Someone correct me if I'm wrong, I've never read that this is the case but IMO this is a good reason for break in.

 

[IndyMX]

I just rebuilt my motor on my YZ250. I just started it up, and let it idle for like 10min or so, (like to running temps) then shut it off and let it sit for about 2 hours until it was Completely cooled down and do it again, and let it completely cool down. then just putt around on it for awhile, never going past half throttle for almost a full tank. Then started to ride it like a normally would... well working up to it in little steps. Motor is still working and going strong... Thats what a couple people told to me to do atleast, and seemed to work good.

2 hour cool down isn't really necessary, about 15 or 20 minutes is fine..

I've heard people who do a complete heat cycle, and I've heard of others who just get on and rip.

Both claim to have bikes that have lasted a long time.

I prefer a couple of heat cycles.

As for oil, I prefer Shell Rotella-T 15w40 in my gear boxes (crank case is oiled thru the premix). If you want to spend 11 bucks on a quart, go for it.. but really now, if you change oil often, the 11 bucks per gallon oil is just fine.

I've even let the Rotella-T settle after draining it from the bike and dumping it in my POS Chevy S-10.

 

[madmike90]

I've even let the Rotella-T settle after draining it from the bike and dumping it in my POS Chevy S-10.

haha i hear you on that one, i had a 4 cyl s-10 hunk of junk and that thing got all of the leftovers.

 

[IndyMX]

That's what this is.. Burns oil almost as quick as I pour it in...

No need for oil changes, the oil never gets old enough.

I don't think the filter even gets oil into it.

It knocks like crazy unless you are on the gas hard, or off it totally. The clutch slips pretty bad, the turn signals don't work and the AC leaks out in a few months.

But it's got new tires and it starts every day.. 225000 miles and counting.

They asked me if I wanted an extended warranty on the tires I just bought. I laughed.. I doubt the truck lasts thru the winter.. I'll be putting these tires on my brothers truck soon.

 

[madmike90]

That's what this is.. Burns oil almost as quick as I pour it in...

No need for oil changes, the oil never gets old enough.

I don't think the filter even gets oil into it.

It knocks like crazy unless you are on the gas hard, or off it totally. The clutch slips pretty bad, the turn signals don't work and the AC leaks out in a few months.

But it's got new tires and it starts every day.. 225000 miles and counting.

They asked me if I wanted an extended warranty on the tires I just bought. I laughed.. I doubt the truck lasts thru the winter.. I'll be putting these tires on my brothers truck soon.

:) if you werent so far away i would say you have the one i got rid of, that explains my old one to the T.

this thing was a weird purple/blue chameleon paint with white racing stripes, god awful ugly and couldnt barely make it up a hill if i hit it going 80....

 

[IndyMX]

Mine is silver, and I've had it for 4 years.. It was junk when I got it.

If I drive over 70 for more than a few seconds, it shuts down.. Will only do about 55 or so until it's gets a good hour rest..

 

[madmike90]

Mine is silver, and I've had it for 4 years.. It was junk when I got it.

If I drive over 70 for more than a few seconds, it shuts down.. Will only do about 55 or so until it's gets a good hour rest..

lol maybe mine wasnt THAT bad.

i must say though, i do miss it for just tossing the bike in the back and going riding.

the small bed made it a cinch to hook the bike up myself.