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Crf250x shim stack advice

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I just ordered lighter fork springs .40

According to Dwight rudder formula for sag.

Riding single track tight woods.

I'm already full fast on compression.

Anyone try the race tech gold valve?

Any valve shim stack recommendations.?

C rider, 175lbs

Thanks.

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No doubt, I have a crf250x as well, I think stock is .42 and is already way under sprung for me and you. My tuner says I at least need a .45 and strongly recommends me to get .46 and I'm a C class rider right at your same weight, tight, single track etc.. .40 is super super under sprung!!

And wouldn't full fast be rebound, and full compression be hard?! If your at full hard already on compression w/ a .42, when you drop down to .40 your gonna be further in the hole... I think your going backwards here...:lol:

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Agreed, for a 175 lb rider, you should be looking at around .45-.47 kg/mm fork springs. Reason being is that the springs are what hold you up higher in the stroke where it is plusher. If you have springs that are too soft then you blow through the stroke to where it is generally harsher.

You don't need to go the gold valve route for a good setup. With just some shims you can have a pretty good setup for cheap.

As far as a shim stack to try out, if you send me a PM, I can give you a full stack that was recommended to me by theDogger that works well.

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I know the srpings sound light, but I did the sag measurement several times.

I'm at 50mm for rider sag with gear for the front and 100mm in the rear. I do have higher handlebars and my footpegs are lower and further back in the mounts so maybe that is enough to take the weight off the front. I also checked to be sure the front wheel was mounted square.

I think you are right that I will blow through the travel under brcking ans was hoping to adjust the compression valving to prevent this.

Right now both the compression and rebound are set full SOFT, I said on my previous post both were full fast which I mean full soft and very little rebound.

Depending on the spring calculator you use you will get different answers. The RacTech one says .44, another one online says .38.

I was hoping for a compression setting that would allow a lush ride but prevent brake dive, is it impossible to have both?

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I know the srpings sound light, but I did the sag measurement several times.

I'm at 50mm for rider sag with gear for the front and 100mm in the rear. I do have higher handlebars and my footpegs are lower and further back in the mounts so maybe that is enough to take the weight off the front. I also checked to be sure the front wheel was mounted square.

I think you are right that I will blow through the travel under brcking ans was hoping to adjust the compression valving to prevent this.

Right now both the compression and rebound are set full SOFT, I said on my previous post both were full fast which I mean full soft and very little rebound.

Depending on the spring calculator you use you will get different answers. The RacTech one says .44, another one online says .38.

I was hoping for a compression setting that would allow a lush ride but prevent brake dive, is it impossible to have both?

what's your static sag front and rear. can't be where it needs to be, it's impossible. you can make almost any spring have 100mm rider sag in the back but your static will be way out of wack. you have to have some preload on a spring to make it work right. Dwight has gotten into some pretty lengthy discussions on this board defending his methodology against some pretty damn good tuners. you should search them and make your own assertion on what you think.

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Static sag for the rear is 30mm with rider sag at 100mm

I am at the max for preload for the rear spring.

The front static sag is 20mm, with rider sag at 50mm

I have looked at a bunch of Dwight's posts and that is what led me to purchase the lighter front spring. It was only 100.00 dollars so in the grand sceme of things if it is too light I can always go back.

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Static sag for the rear is 30mm with rider sag at 100mm

I am at the max for preload for the rear spring.

The front static sag is 20mm, with rider sag at 50mm

.

Your rear sag is ok (although I like 35/100-105) but I'm having a hard time believing your fork sag numbers. Either you have really stiff springs installed already or you've got fork bind or internal issues.

Like everyone else said .40 is not going to work for your weight, esp if you left the stk shock spring on & you can make those forks work well without the bling bling valves....

doc

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Your rear sag is ok (although I like 35/100-105) but I'm having a hard time believing your fork sag numbers. Either you have really stiff springs installed already or you've got fork bind or internal issues.

Like everyone else said .40 is not going to work for your weight, esp if you left the stk shock spring on & you can make those forks work well without the bling bling valves....

doc

I have the stock front springs installed, 0.42

Moto-Pro gives a suggestion of .38 for Enduro riding.

I guess I will install them and see what happens.

I will let you know how it ends up.

Thanks.

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i think you can run with 0.42 on front.with a softner mid valve,i like remove 2 20x0.10

more float and a soft valving on all the fork,you can run 300-310 cc of oil.that s a good start for your fork before make spring change i would try that

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I have the stock front springs installed, 0.42

Moto-Pro gives a suggestion of .38 for Enduro riding.

I guess I will install them and see what happens.

I will let you know how it ends up.

Thanks.

Must be some stiction then because even with stock springs it should have more than 20mm's free sag.....

doc

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Going to have to agree with the above. If you're only getting 20/50 sag using .42 springs on a 250x with your weight then you either have a stiction or binding issue. Could be a seal issue, bushing issue or perhaps a misalignment issue...but the numbers point to there being some kind of issue.

I helped someone setup a 05 250r recently and he weighted 185lbs and had around 65mm of sag on .43 springs.

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Qiuck question, will an 04 R exaust bolt up on an 06 X? Both bikes are 250's. Thanks

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I have the stock front springs installed, 0.42

Moto-Pro gives a suggestion of .38 for Enduro riding.

I guess I will install them and see what happens.

I will let you know how it ends up.

Thanks.

Go to Race Tech web site and use the spring calculator for forks and shock. Call them to get advice. Then call Factory Connection and get there recomendation for spring rates for your riding style, bike and riding weight.

I am with the other guys. The springs you ordered are to light.

Go to the 450R thread and look under the stickys. the dogger has a great thread on revalving.

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Qiuck question, will an 04 R exaust bolt up on an 06 X? Both bikes are 250's. Thanks

Yes, it will work. You should expect a slight loss in low end power in exchange for added top end power. Be sure to rejet.

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Qiuck question, will an 04 R exaust bolt up on an 06 X? Both bikes are 250's. Thanks

I think after 05' they changed the mount location.

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Qiuck question, will an 04 R exaust bolt up on an 06 X? Both bikes are 250's. Thanks

Yes, thats what you want, an 04 or 05 R header pipe for any year 250X:ride:

You need to be in the crf250x fourm with the rest of us:bonk:

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I just bought a used 05 R head pipe from a guy to put on my 07 250X. I was told you'll loos e alil bottom, but you'll gain it up mid and top, and its worth it. Bolt it on, see how you l,like it. Thats what im gonna do, hell, for $50, its a cheap upgrade on my exhuast!! And I'm removing the baffle out of my tail pipe and adding a tip w/ a screen, thats $50 new. Looks good and sounds good I hear, and helps out too!! Should be a good package after I throw the JD in there!!

http://2rracing.com/catalog.aspx?Sto...&DeptID=260737

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Static sag for the rear is 30mm with rider sag at 100mm

I am at the max for preload for the rear spring.

The front static sag is 20mm, with rider sag at 50mm

I have looked at a bunch of Dwight's posts and that is what led me to purchase the lighter front spring. It was only 100.00 dollars so in the grand sceme of things if it is too light I can always go back.

I don't know where these guys are getting their information, but it is wrong. Your numbers look about right, if not on the stiff side. Recommended springs for my 210# weight, is 0.45. This is for off-road riding, not MX or SX.

Incidentally, you are looking at increasing your spring rate a whole 5%. Don't expect to notice any difference. (Industry standard for spring rate tolerance is generally about 5%)

JayC

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