rmracer

Member
Oct 27, 2004
78
0
I was wondering if a 1998 rm 80 has nicasil coating. :think: I believe this coating is on the cylinder to prevent damage from the piston. Is this where it is? :ohmy: Also, if you bore it out, do you have to reapply the coating to the cylinder? Do you usually bore it out when you do regular maintenence on the rings and pistons or do you lightly hone it to make it smooth?Thanks
 
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Bodge

~SPONSOR~
Oct 4, 2003
481
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Yes, the cylinder is plated. If you bore it out( i dont know why you would unless you are going w/ a 100cc kit or something) it must be replated.
 

rmracer

Member
Oct 27, 2004
78
0
RM 80 cylinder Question

Hello again,

Today I took my cylinder down to a machine shop and had it honed to clean it and put the grooves back in. They said that my cylinder didn't have a nicasil coating on it :ohmy: My bike is a 1998 rm 80. I thought these were nicasil coated :think: They also said that I would have to get a oversized piston 0.01 over stock. :| I don't know if the person I bought it from had bored it out, but I thought you could not bore nicasil cylinders. :ugg: If he did bore it, he didn't replate it. Is it bad to have it not replated or is it okay with the exception of not as much durability. Help me, please. I'm going crazy not being able to ride my bike. :eek:
 

minutz

Member
Feb 6, 2000
160
0
You should be able to see a steel sleeve pushed into the cylinder somewhere, top, bottom or in the ports. I don't know about 98's but I know a 94 had a steel sleeve. Give Eric Gorr a call I'm sure he can answer your question.
 

rmracer

Member
Oct 27, 2004
78
0
Thanks minutz,

After further looking, it does appear to be a 1/8 thick piece of metal(steel?) in the cylinder. I don't see a coating on it. Should I be able to see the nicasil if it has it? I thought that bikes this new had nicasil plating. I'm thinking about just getting the oversize piston and goin with it. What do ya'll think?
 

minutz

Member
Feb 6, 2000
160
0
Don't quote me but I think the newer 85 rm's are coated. Its been awhile since I worked on an rm 80. If you can get a 0.01 oversize and and get the proper clearance it should work. I remember them being available in half mm. sizes. Call Eric Gorr (1-630-289-5645) he can set you up on the right way to do it.
 

minutz

Member
Feb 6, 2000
160
0
I almost forgot your other question about the plated cylinder, use a magnet and see if it sticks, if it does it a steel liner.
 

rmracer

Member
Oct 27, 2004
78
0
I just tested the magnet thing on it and it stuck. I guess it is a steel cylinder. I'll go with my machine shop since they knew what they were talking about. They got the .01 oversize piston in today :worship: Now i can go ride :yeehaw: :yeehaw:
 

minutz

Member
Feb 6, 2000
160
0
Cool, make sure break it in and warm it up before you go w/o that steel does not expand as fast as the aluminum piston. You don't need to cold seize it after all that.
 

rmracer

Member
Oct 27, 2004
78
0
I got the oversize piston today( .01 over). I put it into the cylinder and it felt a bit loose. when i held it up to a light, i could see light passing through the gap. Is it supposed to be this loose or should it be tighter fitting?Thanks.
 

minutz

Member
Feb 6, 2000
160
0
Are you putting just the piston or the ring also? Gentley insert the ring only, from the top of the cyl. ( don't bend it ) then push it about an inch or so from the top with the piston upside down and check the gap, if I remember right it should be about 10 to 12 thousands of a gap.
 

rmracer

Member
Oct 27, 2004
78
0
My previous post was just with the piston, not the ring. Everything checked out to be fine according to my manual, so I just have to wait for the dealer to get the springs in for the exhaust valve. The dealer's are very slow, it is better to go to a store and order things probally. Idealer's are getting worse for customer service. hopefully i can ride next weekend. Our snow just melted today. thanks for all the help
 
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