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 Post subject: 78 RM250 forks
PostPosted: Wed Nov 17, 2010 3:22 pm 
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Joined: Tue Nov 16, 2010 1:10 pm
Posts: 1
Hi to all,

My name is Russ. I live in Washington state, the central part.
I am new to this forum, but I have been looking in from time to time to take advantage of the good information available here.
I have been into the older MX bikes for a couple of years now. I began with a 78 YZ400E which I still have.

Last year, I purchased a used (very) 1978 RM250, pretty well thrashed. I should have looked at it a lot closer than I did. You live and learn.
It needed a lot to get it even ride able, let alone race ready.
I spent the better part of last spring and summer not to mention lots of $$ to get it ready to do some evolution class races here in the northwest. I did its first race at the Hammer & Tongs season closer and the bike lasted both motos without any mechanicals. Everything worked great except for the suspension. It really sucked, completely sacked on both ends. I remedied the rear already with some brand new Works shocks with remote res.
The front however I am not sure what to do with? It seems like a simple change of the fork springs would be the most sensible to start with, but I am somewhat confused by what I found inside the legs. The springs are much shorter than what I expected to find.
They are 17 1/8” o.a.l. with one end of them wound to a taper.
There is a 2 ½” long spacer on top of the springs. They looked home made. It looked like a drunken monkey cut them with a dull hacksaw.

When I checked on the Alpha Sports web page on the parts schematic I found two models of forks to choose from for 1978. It shows a RM250C and a RM250C2. The schematic for the C2 looked closer to what I have.
I am not sure what model I am dealing with. My frame ser.# is 27817 and my engine ser. is #27945. I was pretty sure that my model frame wise is the “C” because the bike when I got it had a steel swing arm and alum.gas tank. But from the info.I see in the parts diagram they look to be from a C2 model. I think I just have a bastardized mix of everything.
I have since installed an aluminum swing arm from the C2 model purchased from e-bay, a Clarke plastic gas tank, circle F pipe, and countless other oem parts that needed replacement, anyways my question is does anyone know of a good source for new front springs as I described or any other good fixes to make these perform better?
I called Race Tech. and they didn’t show an application for any RM 250’s at all. He has something for RM 400. Would they work?

Thanks in advance for any advice or suggestions.

Russ


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 Post subject: Re: 78 RM250 forks
PostPosted: Mon Dec 06, 2010 1:38 pm 
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Joined: Fri Apr 04, 2003 11:34 pm
Posts: 43
Location: Daytona Beach, FL
Hi Russ,

I think the Alpha Sports page has the parts fiche backwards when it coms to the RM250C and C2 models. The forks for the '78 RM400C will work for your RM250C\C2 as they are basically the same forks (triples too). I've had a couple of the RM250C2's and they are great bikes. Once you get the front end sorted out to your liking, you'll enjoy it. Good luck!
Kevin


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