Which USD forks should I choose?

OK, so I'm kinda thinking more and more on doing the swap and have narrowed down my choices to getting a set of the new twin chambers CRF forks along with the triples , wheel, axle and probably the stem from Emig. My question is whether I should go for the 250R, 450R, 250X, or 450X forks.

For the obvious reasons(enduro and not mx) I'm leaning towards the X but don't quite know if there are any differences between the forks on the 250X and those on the 450X.

I'm 5'11'' and weigh about 170lb without the gear and 180lb with the gear on. I really like the forks to be plush. Heck, I wont be doing any 20ft jumps or anything like that. Simple off-road riding. With occasional smaller jumps..:cry:

I read in a thread here in TT that the 250R springs are actually softer than the ones on the 450X. It's the valving that makes the difference. So, do you think I'd be better of getting the R's forks and send them in for a revalve? Or should I stick with the X's and not have to revalve them? :):applause:

Tell me if my thinking is wrong. the X is factory set-up for enduro.

The R is set up for mx.

Go for the X and forget about revalving. (could save a few $$$ too)

I'm pretty sure the only diff in the 250 and 450 X forks is spring rate, I'd say get the X forks, and if you know a machinist get the stem turned down. The emig is pretty but you can machine your XR4 stem for half the price. Then again, with the dollar being week you are in a good place right now.

My riding buddy just traded his crf450x for the r and the forks are night and day. I am talking stock here, the x fork is much softer, the r fork is very stiff and the 08 has midstroke harshness.

I rode his 07 X and to be totally honest with you his stock setup rode almost identical to my 97 XR4 fork and the x owner agreed, all I have done to my fork is change the oil and setup the compression and rebound for my weight and riding style.

I haven't rode a xr with a crf fork but from riding his bike alone I would never dish out the dough to convert over myself and although I am a beginner I mx my bike and hit 25-30ft jumps with no suspension issues what so ever.

The twin chambered Showa forks are all the same with the exception of springs and valving. You should find some lightly used with spring a rate you can use like the CRF250r at .45 kg. I would expect to re-valve what ever set you end up with to fit your riding style, skill level, and intended purpose. Stock valving works out just right for very few riders. Sure you can play around with it and make it work, or be a compromise of this or that, but you are still settling for less than exactly what you want it to do. The best suspension you know is the best you have ridden.

I rode his 07 X and to be totally honest with you his stock setup rode almost identical to my 97 XR4 fork and the x owner agreed, all I have done to my fork is change the oil and setup the compression and rebound for my weight and riding style.

I haven't rode a xr with a crf fork but from riding his bike alone I would never dish out the dough to convert over myself and although I am a beginner I mx my bike and hit 25-30ft jumps with no suspension issues what so ever.

well my bike is sprung for me front and rear..but holy crap somebody besides dwight rudder agrees with me :applause:

also seldomly mentioned on here in the usd threads is are people also setting up thier rear suspension properly when the do the forks also? a under or over sprung shock or improper shock settings will make your front end feel bad also and both really should be serviced and set up at the same time. you see some ohlins on ebay once in a while.. the rm250 forks are showa i think and people generally like them offroad with stock valving for mx forks.. im not sure if anyones put any yz250 forks on thier bikes but i dont see why you couldnt put them on and they are known to be the very very good

well my bike is sprung for me front and rear..but holy crap somebody besides dwight rudder agrees with me :applause:

also seldomly mentioned on here in the usd threads is are people also setting up thier rear suspension properly when the do the forks also? a under or over sprung shock or improper shock settings will make your front end feel bad also and both really should be serviced and set up at the same time. you see some ohlins on ebay once in a while.. the rm250 forks are showa i think and people generally like them offroad with stock valving for mx forks.. im not sure if anyones put any yz250 forks on thier bikes but i dont see why you couldnt put them on and they are known to be the very very good

You can put any inverted forks on an XR. KX forks go for dirt cheap. The only issue is machining your stem, and of course, you'd need the entire front end including brakes for a KX or YZ front end.

I've been doing some -search and learn before you ask- thing and instead of simpler answers all I got is more questions.:cry:

So, I went to racetech's website and checked the spring rates for various models.

The 01 XR400R (my bike) is in stock form set up for a rider of about 200lb. That comes according to the stock shock spring rate.

The 01 XR250R is set up for a rider of about 175lb. Again according to the stock shock spring rate.

Yet both bikes share a somewhat similar stock fork spring rate.

.398 for the XR250

.400 for the XR400

:applause:

Is there something fishy going on in here or did I misread something.

Shouldn't there be a stock fork spring rate for the XR400 something like .46 instead for the small .4kg which again according to racetech would be ideal for a rider of 100lb?? According to racetech, .46kg would be the ideal rate for a rider of 200lb (the bike's ideal rider for the stock shock spring rate)

I don't know about you, but my head is getting dizzy here and I'm not even done yet!:eek:

I ckecked the spring rates for the CRF450X and the bike's stock shock is for a rider of about 200lb. Just like my XR400! So, I guessed that since the bikes' rear suspension is tuned for the same rider weight, the same should count for the front suspension! Right? I hope you're following me here, cause I don't know if I can repeat this (when I'm done writing this post, I think I'm gonna have to read it again..)

My bad!! The CRF450X has a front spring rate of .45kg which according to racetech is an ideal spring rate for a rider's weight of 170lb (My weight) and not 200lb (shock spring).

This is getting a bit long but here it goes.

My stock XR400 front suspension is really nice and plush and for a beginner in off-roading like my ugly mug is a good start. But just like Rockjockey nicely put it out, "The best suspension you know, is the best you have ridden"; Hence I started looking for the swap in USD.

So where's your question you might ask? Well my whole post is a big ?, but to be more thread-specific, do I really need a spring of .45kg hence my options are the forks from the 250R and 450X, or could a softer spring be better?:)

Bare in mind that although a beginner in enduro, I'm a quick learner and can keep up with much more experienced riders. I've even started to ride more standing up than sitting down!!:eek: Now that wasn't so relevant but heck, I wanted to throw it out too!!:foul:

Ouff!! I'm tired! :banghead:

Why do you have to machine the stem on the tree? I pressed out the stem form the XR and made a bushing to press in the KX250 tree so I could press the stem back into it. I did no machining on the XR stem. Did I miss something?

Why do you have to machine the stem on the tree? I pressed out the stem form the XR and made a bushing to press in the KX250 tree so I could press the stem back into it. I did no machining on the XR stem. Did I miss something?

I was actually thinking of CR forks when I made that statement, but even in that case, you don't actually have to machine the stem, assuming you can find the right bearings and hardware to make it work.

Why do you have to machine the stem on the tree? I pressed out the stem form the XR and made a bushing to press in the KX250 tree so I could press the stem back into it. I did no machining on the XR stem. Did I miss something?

when some guys put USD forks on their bikes, they machine the CR stem so that it still presses into the cr triple but is machined to the xr400 length and diameter so you can use the xr400 bearings and nuts.

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