Tips for first start after rebuild

Last weekend I finished rebuilding most of the gearbox and put new rings in my 02 WR426. I assembled the motor and put it in the bike last weekend, but had to get a couple of things during the week (oil filter, etc).

Throughout the assembly i coated most parts with engine oil or lubricant re the manual, but my concern now is the fact that it's been sitting with no engine oil apart from the coating I gave some of the parts for a week.

I've put oil in the reservoir as per normal, but am worried that the majority of the motor will be running dry until that oil gets around.

Would kicking the bike over very slowly with the kill switch on pump oil through the motor? Any tips re the safest way to do this? I don't want to undo all the work i've done.

Yes, if you give the bike 20 or so slow kicks with the ignition off (removing the spark plug makes it a lot easier) you should get enough oil around to lubricate everything well enough until you start the engine.

No need to do anything out of the ordinary. Think about the bike when new. Sat in a crate for months. Dealer uncrated it, put the front wheel, bars and stuff on, fired it up. Just be gentle for the first five seconds till oil is flowing.

Then break it in the mototune way.

Thanks guys.

Fired her up this afternoon. Started third kick. Ran beautifully. One thing though, there was a slight bit of oil in the two bolts (which point down) on the side of the motor that hold the head and the cylinder together (left side). Is it possible for oil to leak into there from somwhere in the head? I tightened them to specs with a tension wrench so they shouldn't be overtight. Maybe they had some oil in them and I didn't notice when I put them on. Bit concerned. But otherwise perfect.

Clean the area completely. I use a weak cleaner like Benzine. Run the bike some, if it persists, you have a problem, if it does not re-appear, then it must of been ooze from the build.

You may just have had some assembly oil leak down there.

Going through any kind of break-in is a waste of time in MNSHO.

I don't break in anything anymore. I do change the oil and filter after the first ride.

Hmm now I'm really concerned. Good news is the oil on those bolts must have just been assembly oil. The bad news is the base basket is leaking for some reason. As mentioned, I tensioned everything as per the book. Followed the directions to the letter. I've only taken it for a brief ride - probably half an hour. Can it take a ride for the gasket to bed in? Or am I going have to pull the motor down again?

I just finished doing an entire bottom up rebuild on my '03 WR450, and thankfully never had any leaks. Did you use new gaskets and clean the surfaces spotless? You said you torqued the head down to spec., (just trying to help) did that include removing and re-greasing the bolts and torquing once again, then the 90 degree turn on each bolt and then turning another 90degrees using the criscross pattern? If you did all of this, i'm afraid you may have to pull it out again and figure out why it's leaking. Hopefully you don't have to. May have to use a engine rebuilding silicon if any of the faces are marked up at all.

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