125-200cc WR125: Need guidance with top end job

I wish. They were just shipping the parts today. I've still got a bit to do I'm afraid. I've got to either flush the crankcase out or split the cases and inspecting, cleaning and perhaps replacing parts. Ugh. I hate have to get in to this with such a new bike, but that's the way it seems to be.

Scootskipper,

I really don't think you need to split the cases. Do the flush if you are concerned with shrapnel still being in the bottom end. My guess is that anything that came in is also long gone after doing its damage. If you can feel no notchiness in any of the bottom end bearings and have no end play in your rod, I would guess you are good to go. If there are particles lying in the bottom of your cases they will come up when you turn it over in the oil film. There isn't that much room down there. At the least try using a syringe and inject oil through the port holes that access the bottom end crank bearings and then suck it out with a tube on the syringe doing all this with the rod at top dead center. Then also flush some oil through the rod bearing and repeat with the suction. Should be able to get it completely clear doing this and leave extra oil in the bottom so that when you first start it up it will blow it all up and out the exhaust port. Just some ways to get the bottom cleaned out of any particulate.

Walt

You are going to pre-lube your exhaust silencer bearing at the same time.

Whatever may have gotten in your bottom end is gone now...long blown out. If there is no up and down play on the rotor and the rod does nto go up and down and it all seems smooth just put a new piston and rings on it and ride. You'll damage it more pullin' it apart.

I've flushed out busted piston pieces with kerosene in the past.

Norms old 02 125 just lost a main bearing after 8 yrs...I DNF'd but would have finished if it had happened during the 2nd half of the race.

It still runs after 36miles of roaring!!

Flushing crankcase

I was speaking with my friend who has been a motorcycle mechanic and dealer for many years. He explained how I can remove the crankcase seals and flush the crankcase with kerosene. I like that approach. I called Hall's and ordered new seals right away.

Exhaust silencer bearing

Thanx Wally, I'm planning to just flush it for now unless I encounter something that compels me to do otherwise. Since I have cleaned the spooge off I suppose that I will need to pre-lube my silencer bearing.

Progress report

My seals arrived from Hall's, so I now have all the parts that I ordered. I quickly realized that accessing the right side seal wasn't so simple, plus the swing arm spindle goes through the casting and I didn't seem to have a socket that would work. I did, however remove the flywheel, stator and left side seal. With the bike on the side stand, I poured kerosene in the top and caught it in a plastic pan as it drained out through the main bearing. I kept getting shiny fragments of metal in the kerosene I washed a couple of quarts of kero through the crankcase and was continuing to get very tiny pieces of shiny metal. I decided to cry uncle at that point and hand it to a pro. I don't have the tools to proceed with further dismantling and since I am a woodworker in the middle of a project, my shop is a hostile environment for an engine undergoing major surgery anyway! This is a disappointing development. I know that it is now in capable hands and hopefully I'll have a bike again, but that's how it is going.

Sorry to read that David. I was crossing my fingers for you and hoping for the best. Well it's so hot I think you would just catch fire riding it at this time. You are welcome to ride either one of mine if you want; I am still mending for a couple more weeks.

That's a mighty nice offer John! You're right, it has been awful hot. I have to admit that I haven't been thinking about riding too much in this weather. I do get out early and ride the bicycle some days. How is your mending process coming?

I am mending right along. Ribs are doing very good just tender inner body parts. I think I'll be riding in a couple of weeks. If I can get the 510 sold it will be on a 2010 Gas Gas 300 or 250.

It's alive!

Ken flushed the crankcase until he was satisfied that it was clean. They put the new seals in and partially assembled the engine before returning it to me. I just got it buttoned up and it seems to run just great as far as I can tell. My yard isn't big enough to learn but so much. I want to check the compression before I go ride tomorrow just to see what it is and have a figure to compare to in the future. I'm wondering if I need to go through any special break-in procedure or just go ride. Also, I still had the kerosene that I had flushed through it in a container and I put a magnet in to it and it attracted the metal particles. I'm hoping that it was just from the ring.

Hey you got it running again, great. You are welcome to ride at my place anytime. On the break in I was told a few cycles and let her rip. I'm sure Walt can help you with a proper break in.