Showa 49mm, from rm250

Questions and comments about converting to beefier forks..
ohgood
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Re: Showa 49mm, from rm250

Post by ohgood »

Jason wrote:the top of the caps
I'll pull them apart tomorrow, but this is the cap
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osobad
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Showa 49mm, from rm250

Post by osobad »

just a suggestion here. Having used those forks they should not be unbearable harsh in stock form.I would maybe start looking at alignment of the forks an wheel too. It is very easy to get things misaligned or over torqued when putting stock forks back on much less a conversion. look at the wheel and axle assembly also.Not saying that it is your problem but it can be the cuase of a lot of grief. Did you get all the air out of the inner chamber if it was disassembled? just some ideas
ohgood
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Showa 49mm, from rm250

Post by ohgood »

osobad wrote:just a suggestion here. Having used those forks they should not be unbearable harsh in stock form.I would maybe start looking at alignment of the forks an wheel too. It is very easy to get things misaligned or over torqued when putting stock forks back on much less a conversion. look at the wheel and axle assembly also.Not saying that it is your problem but it can be the cuase of a lot of grief. Did you get all the air out of the inner chamber if it was disassembled? just some ideas

yes, the axle/wheel/etc was assembled correctly, bounced, then finally tightened. I've aligned it without any spacers to test and make sure, with grease all over the pinch clamps, axle, etc. while assembling. I've seen that kind of problem before, yes it's bad.

I've run the tube clamps loose enough they slid up the triple.

I've bled the damping rod/cartridge fully before assembly.

it's the valving.

the ktm 300 forks I had in place were plush. there kdx forks were plush, even with a 4" section of broken spring in one leg. these are harsh
Friedom
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Re: Showa 49mm, from rm250

Post by Friedom »

Those look like 96-98 rm250 Showa 49mm closed cartridge forks.
I had a set on my 92 kdx200. Donnie at ZR1 worked them over for me, and did a little valve work to soften them for trail riding.
When I blew up the top end on the KDX, I moved those forks over to a dr350 and had a great time with them. They weren't the best for street riding (with knobbies), but they sure made my life easier when things got rough.
Kinda bummed that I didn't keep them when I sold that bike tbh!

With THAT said, they're nice forks and Donnie was really excited to see them when he realized what they were, and he took very good care of me and them.

Can't help on doing it yourself though, sorry. Good luck!
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KDXohio
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Re: Showa 49mm, from rm250

Post by KDXohio »

I looked into revalving the forks on my 97 rm250 for the woods I found a really good thread back then with all the shim sizes dia/thickness to put in. If I can find it again I will post the link I absolutely love those forks on my 250 and can run the trails much faster on that than my KDX with old kx250 forks. Don't give up yet.
1990 KDX200 FMF Fatty, Answer VFC silencer, VForce 3 Cage, Wiseco Piston, KX125-J series KYB USD fork conversion, Race tech goldvalves, J series front brake assembly, air-box snorkel removed, Acerbis Headlight, KX450F Front fender, Pro Taper RM bend bars, ASV front Brake lever, MSR Clutch perch and lever, RB Head mod, 36mm PWK carb, Trail Tech Kickstand.
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KDXohio
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Re: Showa 49mm, from rm250

Post by KDXohio »

I think this is what I'm thinking of. You will have to order shims but that shouldn't be too costly.

https://thumpertalk.com/forums/topic/10 ... ns/?page=8
1990 KDX200 FMF Fatty, Answer VFC silencer, VForce 3 Cage, Wiseco Piston, KX125-J series KYB USD fork conversion, Race tech goldvalves, J series front brake assembly, air-box snorkel removed, Acerbis Headlight, KX450F Front fender, Pro Taper RM bend bars, ASV front Brake lever, MSR Clutch perch and lever, RB Head mod, 36mm PWK carb, Trail Tech Kickstand.
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