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USD to Conventional forks swap?

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I've got a 12 CRF 250R I want to try a set of conventional forks on for trail riding, hare scrambles and enduro's. I know I'll need a whole front end to do the swap, I've read the DRZ and RM conventional forks are the best to use. What years of these are the best and are the DRZ and DRZE forks the same? Also anyone here done this kind of swap? 

 

Thanks

Stewart

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I've got a 12 CRF 250R I want to try a set of conventional forks on for trail riding, hare scrambles and enduro's. I know I'll need a whole front end to do the swap, I've read the DRZ and RM conventional forks are the best to use. What years of these are the best and are the DRZ and DRZE forks the same? Also anyone here done this kind of swap? 

 

Thanks

Stewart

 

 

i don't know why you would do this.

your basically

saying you want to do an air cooled swap too.

>.<

 

your forks could be made to work wonderfully.

just takes some know how.

correct springs, oil height, valving, and ics springs.

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Yes you are correct. I’ve had many CRF models over the years, R’s and X’s, 450’s, 250’s all with suspensions mods from FC for offroad and you can get the USD forks to work better. It’s funny you mention going back to air cooled bikes because I can get on my 1990 XR250R vintage race bike that has XR400 forks on it, and the bike is a lot more plush thru the rocks, roots and trail junk than any of my CRF with USD fork and mods have been. I’ve read post where guy have done this mod and are very happy with it. This post is not about how I can make my USD forks work better. I’m just interested in seeing how the  conventional forks  will work with CRF frame and who has done it and which conventional fork would be best to use. I may buy a set to try and if it doesn’t work out I’ll put the USD back on and sale the conventional fork set up. I’m not convinced that the USD forks are better for offroad, MX yes.

 

Thanks

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I have a lot of experience with DRZ forks, and a decent amount of experience working on USD forks to be used in the woods (as a DIY guy, not nearly as much experience as anyone who does this for a living).  The DRZ forks are good quality units, on par with any open chamber USD fork, but the stock valving is terrible.  Fork function & feel is 90% related to the springs and valving in the forks, and only a tiny bit related to the fork type/brand/style.  There is zero reason why you shouldn't be able to get your USD forks to work exactly how you want them to.  If your suspension tuner can't do that for you, get a better suspension tuner, or do it yourself.  If you want your USD forks to feel like XR400 forks, any reasonably competent suspension tuner can do that.

 

DRZ forks are all the same except for some very early S-model bikes, and the SM-model bikes with the Showa USD forks.

 

I strongly recommend getting your current forks to work the way you want, instead of doing a swap.  A swap will require changes to forks, triples, and possible wheel, axle, and brake, and even after you do the swap you'll need to change the fork springs and the valving in the DRZ forks.  You can also get what you want just by changing the springs and valving in your forks, for way less money and effort.

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Yes the steel frame is less rigid than the aluminum frame and lets the XR flex more but that’s is ultimately what I’m after on the CRF. More flex is a good thing for the type of riding I do and the USD forks are more rigid than the conventional forks and they would help with the rigid CRF frame.

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the xr650r fork is also a good fork to use.the flex  of the conventional fork will be better in a woods setup.valving and springs in an upside down fork will never duplicate the feel of a conventional fork.

 

I forget the fellows name,he was an eastern woods racer.he had several different bikes some ktms and some jap bikes.all his bikes ran conventional forks off xr650r.

 

I think for true woods riding any closed chamber fork is inferior to open chamber designs(wether conventional or upside down.)

 

O P  don,t listen to the detractors,it is definatly worth a try.

Edited by cj_wai

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People always say that open chamber forks are better, but I can't see any reason why they would be.  Internally they work the same (in fact, I like the piston/valve geometry on the CC stuff way better than on the big OC USD forks).  I believe that, in the woods, OC and CC forks can be made to work equally well.  I also believe that conventional forks can be made to work very well, but I don't think switching to conventionals makes any sense at all.

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The conv forks will be better if you're searching for maximum comfort and tracking over junk. Steering precision will suffer. The drz are great forks IMO.

As someone already stated you'll run into many issues but the end result will be impressive if you're just trail riding.

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I've got a 12 CRF 250R I want to try a set of conventional forks on for trail riding, hare scrambles and enduro's. I know I'll need a whole front end to do the swap, I've read the DRZ and RM conventional forks are the best to use. What years of these are the best and are the DRZ and DRZE forks the same?

you are frickin' nuts! now that that is out of the way...

DRZ-E/K and DRZ-S forks have been the same since 2002. prior to that, the S had different (crappy) forks. after that, they have not changed substantially (if at all).

the SM has (and always has had) different, inverted, forks.

Edited by LittleRedToyota

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I see bikes around here that have been switched to conventional forks.  They prefer 2 stroke RM forks.

 

I think Applied Racing makes or did make triple clamps to put them on a CRF Honda.

 

The guys who did it raved about it.

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+1 to Kyle. Only benefit I see in doing such swap is that conventional OC forks are much easier maintenance than CC USD forks (simpler construction, easier oil changes) and are probably less prone to seal failure. If it comes to flex, I wouldn't jugde so easly which is more flexy, because that strongly depends on their mechanical construction (wall thickness, diameter etc.)

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Ok guys I should of thought out my post better on what I was looking for better. I want to here from guys that have done this and what forks they used and how it all worked out for them. I'm NOT looking for why the USD forks are better or why I should just work on mine or how crazy this all sounds. Believe it or not there are guys running conventional forks on modern bikes with good results.

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For the RM you want 1997 or 1998 rm125/rm250 forks. They are twin chamber and look very similar to early 2000 showa on the inside. Springs are limited depending on your weight but you can have some made or grab a set of drz springs and mod the spacers in the fork. I can post the triple clamp/steering stem info for those forks later tonight. I have a triple clamp set laying on my shelf from a pair of those forks.

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But the RM forks are twin chamber, those don't work well in the woods! :rolleyes::lol:

Edited by Kyle Tarry

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1989 RM125 conventional 46mm forks. The best for enduro riding.

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