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92
Joined
5/18/2017
Location
Homestead, PA
US
I need to have a second cylinder I have bored up to the first step - 67.25mm. It needs about .008 taken off. My question is when the cylinder is bored to this next step, will the boring effect the power valve clearance when they are installed? Would the power valves also need to be cut down???
Paw Paw
New member here with a 1988 RM250 I just bought. I plan to tear it down this winter and rebuild the engine.
As part of the prep I have been scouring eBay to see what's out there. In every picture I see of a 1988 cylinder a sleeve is present.
Was the 88 RM cylinder definitely plated?
The bike I bought has an oversized piston so I don't have a plated cylinder. Of course it may have been sleeved.
Sandman how does your bike run with the sleeved cylinder?
Nice to meet everyone. I look forward to learning a lot.
Mike
FYI, join this Facebook group as well. Lots of good people over there to help.
https://www.facebook.com/groups/fullfloater/?ref=nf_target&fref=nf
My 88 build, I was able to locate quite a bit of new parts using Partzilla and eBay. The cylinders are a hard find and you have to be really quick on the spot to get one on eBay. The 88 model uses a lot of specific parts made only for that year which can be a bit of a hassle. The swingarms are an instance of this. They only fit the 88 model. They are also known to crack on the pivot points requiring a welder to weld the aluminum. It's almost a given you'll have a cracked pivot. I personally have three arms that were all cracked!
That 88 cylinder is a bit different as well although an 87 and I think and 86 cylinder would work on the motor. The 88 had larger ports. Another thing different with the motor is the clutch. A true 88 motor will have 15 clutch plates where the 87 has just 11. I found this out the hard way when I tried putting 15 plates in my motor only to not be able to squeeze the clutch lever.
Pay close attention to part numbers also! The 88's have 26C in the numbers while the 87's have 00B. Just a tip there!
sandman and paw paw are two great guys who helped me tremendously! Find sandman's 88 RM250 build thread and read through it.
Good luck!
The Shop
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