98 RM250 Dual Chamber fork Oil Change

[MrPulldown]

Hi all,

New memember here. I have been reading TT post and articles for a few years and finailly joined.

I ride a 94 DR350SE. After a couple of years of owning it I have exceeded the capabilities of the suspension. This year I plan on revamping things a little.

For the front end I have aquired a 98 RM250 fork, which I plan on grafting onto my machine come spring. From my reading, these were one of the all time best forks made. 49mm showa dual chamber conventionals. The forks are in great shape. They feel buttery smooth, with both rebound and compression danmpening working. I am tempted to jsut slap em on. But prior to the install I figure I should at least change out the oil.

How do I do it. I have read about every "how-to" out there and seen a ton of videos including the rocky mountain ATV one for dual chamebr forks. All the write ups are of USD forks,plus they go through seperating the two halves due to the bushing, and seal replacement. Do I really need to do all this if I am jsut changing the oil. Can I just pop the top cap off, dump the oil, give her a few pumps and fill it back up. What about the inside chamber, what does the air bleed screw do.

Fianlly how much oil do I fill it up with. I have scoured the web looking for this spec. 5wt oil seem to be the consensouse, but what about amount. I have seen numbers from 205cc to 470cc per leg?? Is there also a height to the top measurement?

Please school me Moto peeps!

Edited February 17, 2012 by MrPulldown

[Jeekinz]

Those forks are good, I have them on my 96 RM125.

I bought a service manual off Ebay for like $10. The bottom cap is a little tricky, if you don't install it right it will unseat once you put the bike on the ground. Ask me how I know that. Plus with the manual you have detailed info and oil capacities.

[MrPulldown]

Thanks. Did you get a factory manual or a Cylmer? THere is a difference in the top cap betwee the 96,97 and the 98 forks. Is everything else the same. Can you list the oil capacity number for me. Thanks!

Edited February 17, 2012 by MrPulldown

[Jeekinz]

No, never Clymer!

My book is only for the 96 RM125. I'm pretty sure the 98 RM250 will have different capacities.

[kan3]

Thanks.  Did you get a factory manual or a Cylmer?  THere is a difference in the top cap betwee the 96,97 and the 98 forks.  Is everything else the same.  Can you list the oil capacity number for me.  Thanks!

Almost every part is different in one way or another between 96-98. I would start around 250cc and work your way up if you're bottoming.

[ventabular]

There is nothing the same in the internal parts of these three years of forks except the bearings, and seals.