Correct Spring Rates

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SOARSKI
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Correct Spring Rates

Post by SOARSKI »

I'm beginning to work on suspension and want to get it set up for me. I weigh between 205 - 215lbs(it's a summer winter thing) and 225-235lbs with gear. I've looked at the calculators at racetech, mxtech, and fredette's recommendations. I want to make sure the bike is well balanced suspension wise front and rear.

1. 5.2 seems to be the suggested weight spring for the shock. Is this going to be too stiff? At this time I do not plan to have any revalve work done. Anybody prefer the lighter 5.0 spring in the same weight range? I'm just wondering if I can get by on the 5.0.

2. I have a 2003 KX125 fork that was just professionally serviced by the previous owner and it's all stock(ebay for $100 + s&h). Suggested springs by MXTech .46 and RaceTech .44. Stock spring is a .43. Jeremy at MXTech was strongly suggesting the .46. What do you guys suggest for my weight? I do plan to revalve see next question.

3. I'm unsure which route to take for revalving the forks. I feel confident enough to open them up myself but don't know what kind of results I can expect doing it myself. Are most getting good results staying stock and removing/adding shims? I'm also considering RaceTech's Gold valve kit. I like the fact that its a kit with instructions etc. Would I be better off and get better results just having a pro do the job? Any Pros in the St. Louis MO area recommended?

4. When you send your shocks to be revalved whats usually included? Do some revalves consist of just reworking the existing stock parts? Or can you expect a new piston/valve also? MXTech said they would revalve using existing components for $175.

I've been looking at some post by bradf and what he's done to his forks. Seems like he's had good results, I don't know if this is a job for new guy though.
http://stlouis.craigslist.org/mcy/1558205098.html
I'm still trying to figure out all the acronyms and match the terms to all the parts. Still a little intimidated.

I'm Lost. Information Overload. Suggestions?
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Indawoods
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Post by Indawoods »

I am the same range as you with the same forks. 5.0 spring works fine except when hitting some really heavy stuff. I have never run across a 5.2 to swap so... the 5.0 is what I use.

I also use the stock .43 springs in my 03 KX 125 forks. These were too stiff for woods riding initially. All I did is remove 4 of the largest shims and it works great now.

This all depends on if you are an agressive racer, casual rider or what.

You will have to find what works for you. I have.
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SOARSKI
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Post by SOARSKI »

>|<>QBB<
Indawoods wrote:I am the same range as you with the same forks. 5.0 spring works fine except when hitting some really heavy stuff. I have never run across a 5.2 to swap so... the 5.0 is what I use.

I also use the stock .43 springs in my 03 KX 125 forks. These were too stiff for woods riding initially. All I did is remove 4 of the largest shims and it works great now.

This all depends on if you are an agressive racer, casual rider or what.

You will have to find what works for you. I have.
OK, I'm willing to experiment a bit. I'm working on getting a KX service manual for the forks. I assume one of the PDF versions on the net will do.

I'm looking at the fiche but it's not clear to me where the shims are located.
Is it part 49116, valve-assy in the this fiche?
http://www.mrcycles.com/fiche_section_p ... Front+Fork

I'm also going to have the nitrogen checked in the shock. Do most of you have it filled to 142 psi or some other value and why?[/url]
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Indawoods
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Post by Indawoods »

Yes it is 49116.

I flipped my bike upside down to get to it. I used a 14mm allen socket on a rattle gun to get them out without draining the oil. The nut holding the shim stack onto the valve was not staked on mine... I got lucky.... allot of them are staked and you have to file the stake away before you can remove the nut.

I believe there is a range that the shock is charged to... I think the shop I took mine to charged it to 170 after it was rebuilt.
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Post by riggy »

The shops I have talked with dont buy racetech vavles , They revalve the stock parts the way they want them . I had mine rebuilt stock by a shop . for parts I needed new shock bumper and bushing replaced . for the forks new du bushing and seals . I was amazed at the difference very nice.my bikes a 97 so it needed it for sure . The 01kx 250 forks was a plus too . :razz:
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Post by SOARSKI »

>|<>QBB<
Indawoods wrote:I am the same range as you with the same forks. 5.0 spring works fine except when hitting some really heavy stuff. I have never run across a 5.2 to swap so... the 5.0 is what I use.

I also use the stock .43 springs in my 03 KX 125 forks. These were too stiff for woods riding initially. All I did is remove 4 of the largest shims and it works great now.

This all depends on if you are an agressive racer, casual rider or what.

You will have to find what works for you. I have.
Which four shims did you remove? 4 largest above the the piston, two largest above and two below the piston?

Did you replace the large shims with smaller shims of the same thickness to maintain the height of the original shim stack? If you did do this what position in the stack did you insert them?

Do the 03 KX 125 forks have bladders?

The midvalve is located in the cartridge correct? What are the suggested changes to make to the mid valve? Replace the midvalve with a check valve, remove the bladder etc.
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Indawoods
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Post by Indawoods »

No bladders....

I removed the largest shims at the bottom of the stack closest to the valve assembly I believe. There was a total of 6-8 total all together. It should be shaped like a V. The little buggers stick together so you have to make sure you have them completely separated to get a good count.

I did not mess with the mid valve at all. It seems to be fine now that I removed the shims from the base valve.
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"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
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