93 RM250 Complete Rebuild
- Thread starter JakeBoucher
- Start date
It could be, but I'm almost positive it's from the motor. Found it after disassembly on my little table I was working on.
Started doing small things in the rebuild. I put my crank bearings in, repaired the hole in my case from the damned "case saver", adjusted my carb, resurfaced my head, cleaned up my power valve, installed new reeds, cleaned all the mating surfaces of the cases and covers, other little things. Still waiting on my crank.....
I put my cases in the oven at 210 degrees and my crank bearings in the freezer. Had no trouble getting them to slip in.
On my carb the jets in the bike when I got it were 190 main, 55 pilot, 2nd from the top on the needle, 1 and a half out on the mixture. I'm at sea level, 90 degrees and around 50% humidity and this thing was spooging out of the silencer like no other. It was super flat on top end too. I'm assuming it was way to rich. My service manual says stock is 180 main, 45 pilot, 3rd on the needle and 1 and a half out on the mixture. I have an fmf gnarly though, fmf says with their pipe 178 main, 55 pilot, 3rd on the needle, and 1 and a half on the mixture. I don't understand why the main jet drops when putting an aftermarket pipe on? I've really only done hop up on 4 strokes that's why I was expecting a larger main. Should I start with fmf's recommend jetting?
On my head it looks like a plug electrode must have broken off or something. It's a little rough but I wet sanded it with 400 grit to get rid of any burs or sharp edges. What do you all think about its condition?
The nikasil on my cylinder looks good, I'm going to hit it with a dingle ball hone to mate it with new rings. That's OK right? I only found a little imperfection in the nikasil, I'll post a photo I figure it's fine though.
Nikasil photo:
http://i1375.photobucket.com/albums/ag471/JakeBoucher/Mobile Uploads/1404887877888_zps459c806f.jpg
Head Photos:
http://i1375.photobucket.com/albums/ag471/JakeBoucher/Mobile Uploads/20140708_174208_zpse53da546.jpg
http://i1375.photobucket.com/albums/ag471/JakeBoucher/Mobile Uploads/20140708_174158_zps041ec186.jpg
This is before resurfacing and sanding. Still looks much the same just no rough edges or burrs.
I put my cases in the oven at 210 degrees and my crank bearings in the freezer. Had no trouble getting them to slip in.
On my carb the jets in the bike when I got it were 190 main, 55 pilot, 2nd from the top on the needle, 1 and a half out on the mixture. I'm at sea level, 90 degrees and around 50% humidity and this thing was spooging out of the silencer like no other. It was super flat on top end too. I'm assuming it was way to rich. My service manual says stock is 180 main, 45 pilot, 3rd on the needle and 1 and a half out on the mixture. I have an fmf gnarly though, fmf says with their pipe 178 main, 55 pilot, 3rd on the needle, and 1 and a half on the mixture. I don't understand why the main jet drops when putting an aftermarket pipe on? I've really only done hop up on 4 strokes that's why I was expecting a larger main. Should I start with fmf's recommend jetting?
On my head it looks like a plug electrode must have broken off or something. It's a little rough but I wet sanded it with 400 grit to get rid of any burs or sharp edges. What do you all think about its condition?
The nikasil on my cylinder looks good, I'm going to hit it with a dingle ball hone to mate it with new rings. That's OK right? I only found a little imperfection in the nikasil, I'll post a photo I figure it's fine though.
Nikasil photo:
http://i1375.photobucket.com/albums/ag471/JakeBoucher/Mobile Uploads/1404887877888_zps459c806f.jpg
Head Photos:
http://i1375.photobucket.com/albums/ag471/JakeBoucher/Mobile Uploads/20140708_174208_zpse53da546.jpg
http://i1375.photobucket.com/albums/ag471/JakeBoucher/Mobile Uploads/20140708_174158_zps041ec186.jpg
This is before resurfacing and sanding. Still looks much the same just no rough edges or burrs.
I can not find the washer I previously asked about. I think I will just search each and every part diagram until I find it. How do I know if my bike is the "P" or "R" model? Thanks
Nikasil plated cylinders are to hard to be honed by anything but a diamond hone if you use a stone type hone, it may deglaze cylinder, but it won't remove any scratches or imperfections, it may however, remove some of the plating around the ports if the stone catches it just wrong, I recommend using sand cloth or a scotch brite pad and oil to deglaze cylinder.
Thanks bobkyle!
Crap. So I can use scotchbrite and oil to do it? Would getting a Diamond hone be the better route?
Crap. So I can use scotchbrite and oil to do it? Would getting a Diamond hone be the better route?
I think youll be ok, you can typically get 2 or 3 rebuilds outa one of those before it needs replating. As long as cylinder doesn't have any nicks or gouges.
It has a small scratch but I think it should be OK after honing. How much does replating cost? I know the bike has been rebuilt at least 1 time, I'm not sure how many total though.
Here its about 250$ to replate
Well hopefully I can get by without another. Thanks for the help!
More parts showed up today, still no crank. Got all my seals installed today. Used OEM on the crank seals. I also put my transmission in today. Got it to shift through all gears the first time. It took me close to 2 hours to analyze it and understand how it works, then go through every part and put it all in in order. I Used some scotchbrite and oil to deglaze my cylinder. There is some discoloration on the wall, I don't know if it is normal or not. I'll post a picture and get everyone's expertise. I have a big ole mess to clean up tomorrow!
Transmission:
http://i1375.photobucket.com/albums...obile Uploads/20140709_213254_zps016623dd.jpg
Cylinder:
http://i1375.photobucket.com/albums/ag471/JakeBoucher/Mobile Uploads/20140709_213030_zps0bd40d4a.jpg
Transmission:
http://i1375.photobucket.com/albums...obile Uploads/20140709_213254_zps016623dd.jpg
Cylinder:
http://i1375.photobucket.com/albums/ag471/JakeBoucher/Mobile Uploads/20140709_213030_zps0bd40d4a.jpg
Not what I wanted to hear lol. I think ill have it looked at by someone to be sure. Where is the best place to get it plated? I figure I have to ship it off somewhere. Thanks Mihylo