What to do to forks before conversion?

Questions and comments about converting to beefier forks..
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turtle
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What to do to forks before conversion?

Post by turtle »

I hope to soon have KX125 forks to put on my 220. I am wondering what to do to the forks before converting.

I plan to at least change the oil. Seals are reported to be good. As far as springs, I read on here the stock KX125 spring rate is 0.41. A couple rate calculators said I should be at 0.43, but neither of them had "slow a$$, old man trail riding" in the choices for riding style :wink:, and regardless they will be quite a bit higher rate than KDX springs (what's the stock rate on KDX springs, anyway?). I think I can get by with the stock springs, assuming that is what is in there.

If/when I do want to revalve, who do you go to? I saw somewhere that WER was a good option and they did great on rebuilding my steering damper. So using them as an example, a revalve is $165 (plus shipping). So it ain't cheap.

I am thinking about waiting till I get a chance to ride the bike and see what I don't like, if anything, before spending money on revalving. Is "wait and see" the best choice, even though it means tearing things down again after conversion, or is the need to revalve such a given that I ought to just get it done? I know there will be lots of opinions on this.

Sorry for the long post. Thanks for the wisdom. :prayer:
Bill
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Post by jbowens2401 »

The stock springs in my 2003 kx125 forks actually tested out at .43. For trail riding I recommend a revalve unless you want a lot of deflection. I took mine to a local tuner and he changed the base valve and mid valve and it made a big difference for woods riding. Just my 2 cents
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gsa102
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Post by gsa102 »

I would test ride, so you know what to tell the tuner. To me, the more testing you do, the better. Also you will get some kind of idea if you will need different springs. I prefer to use local people rather than to send stuff away. Ask around at your track or bike shop.
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Post by SS109 »

Wait and see. That is what I did. That way you can explain to your suspension guy what you don't like, if anything, about how the forks handle different terrain. I know I'm glad I did. After riding for a while, and then have them done, my forks are near perfect for just about everything I encounter.

FYI, I have .41's in my KX forks. I weigh 150 pounds (170 with gear). I'm a very fast C/mid-B rider. The forks are just a bit stiff at very slow speeds but are awesome when really flying for my weight.

BTW, Bill, I still haven't heard from your friend!
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turtle
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Post by turtle »

>|<>QBB<
SS109 wrote:
BTW, Bill, I still haven't heard from your friend!
I talked to him today. I'll send you a PM.

Thanks for the input on the forks!
Bill
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Post by ihatefalling »

Congrats on the forks.
You will love them.
If the seals are good, mount'em up and ride them.
My tuner is in NC.
$150 + shipping and all the revalves you can eat till you/he gets it the way you want. Good guy. Tunes and races for a living.

I try not to be a flamer (literally :cool: and figuratively). I have done business with WER several times but, never again. Everyone's experience is different.
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Tedh98
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Post by Tedh98 »

I agree that you should ride them first so you can communicate to your tuner what your likes/dislikes are about the forks. Otherwise the tuner won't have as much to work with as you'd like.

I also agree that you should try to use a local tuner if possible. It is often difficult to get a revalve right on the 1st try. Shipping forks back and forth gets expensive and takes extra time. Local tuners will often meet you somewhere and watch you ride to see what changes need to be made.

You mentioned that you were going to change the oil. Unless you know for a fact that the bushings had just recently been replaced, I'd suggest that you also replace your bushings while you are at it. It isn't that difficult and worn bushings will impact how the forks feel. There isn't much point riding forks with worn bushings and fresh oil and using that as your baseline. If you send the forks in and the bushing are worn, the tuner is going to replace those right off the bat.

If you are up to taking the forks apart, you can learn a lot with minimal effort. Often times fork springs have markings to indicate the spring rate. You can also quickly determine if your mid and base valve have been revalved before. This would give you some idea if you are dealing with stock of modified forks.

Don't rule out doing your own revalve. I don't think you indicated what year forks you are dealing with. If you go to my blog, I've got quite a bit on what I did to a set of '04 forks. There was a lot more info on '99 to '02 forks on two of the other major suspension sites for turning the '99 to '02 MX forks into woods forks. Mechanically speaking, revalving isn't that difficult. The challenge is know what changes to make. That is where those other sites offer a great resource as well as the restacker program.
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Post by heckler »

get the spring rate right before you bother with any revalving.

ride it before you try to get the spring rate right.
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Post by rbates9 »

I would also say to give them a try before you tear them apart. I used about the same forks and was pretty happy with them with no revalve or spring changes. I did disable the bladders tho. If you do a few searches you should find that most people disable the bladders for just about any riding.

http://www.thumpertalk.com/forum/archiv ... 31159.html
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Post by scheckaet »

>|<>QBB<
heckler wrote:get the spring rate right before you bother with any revalving.

ride it before you try to get the spring rate right.
+1
one thing though, race tech (and other) are on the stiff side. According to them the stock were what i needed, but my local tuner told me to go 2 rate lower. I can't be more please with the way they are now.
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Post by turtle »

I've been doing some reading on the forks and have run across the fact that that have bladders. From everything I have seen those will need to be disabled or removed. Does that need to be done before riding with them to see what I like and dont like? Or just do it when I revalve?
Bill
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Post by Tedh98 »

You've got to break down the forks to disable/remove the bladders. It isn't a quick or clean thing to do.

I'd do it all at once - revalve/disable bladders/new seals & bushings.
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Post by rbates9 »

>|<>QBB<
Tedh98 wrote:You've got to break down the forks to disable/remove the bladders. It isn't a quick or clean thing to do.

I'd do it all at once - revalve/disable bladders/new seals & bushings.
I disabled mine before I put them on and it was not a huge deal to do. You could and probably should ride with them still in there just to see the difference.

All in all I spent about two evenings playing around with the forks but I had to replace seals and bushings before I could use them anyways so I just did it while they were apart.
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