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DIY revalve without buying shims

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Is it possible to get my 06 crf250r forks and shock acceptable without buying shims? I'm 155 pounds. Don't ride mx, they are much to firm.

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I've about 160ish and have an 05 CRF that I bought used in 2010. One of the seals started finally leaking so did a full rebuild with the Pivot Works Kit using 350ML per fork (not including the inner cartridges) of 5 WT Maxima fork oil and IMO I'm now changing my fork oil yearly cus it made a HUGE difference for riding single track only.

Then set all the adjusted to stock an made slight adjustments

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Everything is serviced and in good working order. They are just to stiff for what I need.

Will it set anything off balance if I soften comp stacks but not rebound?

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Lets talk forks. If I want softer compression do I take shims out of the stack on the fork cap, or shims out of the stack on the damper rod?

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You could take out a few low speed big compression shims at the top valve, and take out a couple of the biggest size compression shims at the mid valve. Also flip the bleed stack over if it has one, the stack of small shims below the base plate thick washer under the compression stack at the top base valve. 

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I'm not familiar with your bike but I believe you if you want softer compression you could find the compression stack and just put a couple of the bigger shims on the othe side of the little shim.  Or lower the oil a little.  

But I don't know wtf I'm talking about so don't listen to me. 

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What Tom02 said. Remember to shuffle the removed shims in reverse order after the clamp shim to keep the stack "right." and avoid it floating.

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15 hours ago, Berm-Saw said:

Lets talk forks. If I want softer compression do I take shims out of the stack on the fork cap, or shims out of the stack on the damper rod?

Depends.  The base valve on top handles mostly low speed damping.  At higher speeds the mid valve in the cartridge provides the majority of damping.  Usually the mid is the cause of your problems for MX bikes being ridden off road.

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For the forks, if you are willing to buy a few shims, specifically adding some 16x0.10, 14x0.20 on the base valve assy. 
you could easily convert your R settings to CRF250X settings, better suited for off-roading.

 

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Correct springs, 2.5 wt oil at 320 to 360 cc will work wonders and is quick and easy. Better to start with less oil, easier to add than remove. Put an o-ring on the non brake leg so you can measure fork travel.

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Going full crf_x spec might be a little soft. I still like to be hard on it at times. Been thinking about the 2.5 weight. Is 1 liter ehoughf for both inner cartridges?

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On ‎6‎/‎11‎/‎2017 at 4:59 PM, Berm-Saw said:

 

Is it possible to get my 06 crf250r forks and shock acceptable without buying shims? I'm 155 pounds. Don't ride mx, they are much to firm.

 

 

I recently shortened and revalved a pair of 2006 CRF250R forks with help from mlatour and motrock93b.  I just reused what shims I had already which didn't look to be the OE valve stack, it had been revalved previously.  You might wanna disassemble at least one fork and take inventory of what shims you have to work with and then proceed. 

 

2 hours ago, Berm-Saw said:

Going full crf_x spec might be a little soft. I still like to be hard on it at times. Been thinking about the 2.5 weight. Is 1 liter ehoughf for both inner cartridges?

 

It's my understanding the "X" spec is still too harsh for most tastes off road and using lighter weight oil or not filling the inner chamber fully isn't the best way to go.  Might as well just disassemble them and revalve it properly to get real results.  I didn't find it very difficult, only needed one special tool which could be made or purchased inexpensively, the damper rod holding tool.

 

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3 hours ago, Berm-Saw said:

Going full crf_x spec might be a little soft. I still like to be hard on it at times. Been thinking about the 2.5 weight. Is 1 liter ehoughf for both inner cartridges?

I revalved a friend's '07 CRF250R with X specs as he wanted to get more into off-roading,

at 140lbs it ended up being 'just right' for his MX track usage.

The stock X valving specs aren't that soft, initially intended for off-road racing rather than recreational trail riding.

I'm currently on my 8th revalve/experiment on making mine super plush for low speed/rocky trails.

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Correct springs,

This is important. I don't know the stock spring rate for your '06 250R, but they're probably 45 or 46 (assuming you have stock springs). These are probably a bit too stiff for your weight if you're seeking softer forks for trail riding. If you're a super fast A rider, stock may be OK and you'd want to pair them with something like stock 250X valving adding a bit more float at the midvalve. If you're an average speed trail rider, you may want to soften the springs. The good news is that you can put different rate springs to create different average spring rates. You can purchase .42 springs and use one .42 and one .45 to create an effective 43.5 rate. If this isn't soft enough, you can run both .42s. This gives you options to test, just be careful to check preload since springs come in slightly different lengths (+- 5mm).

 

There is good advice in this thread. Nobody can know what valving will work well for you, but there are specific changes you can make to soften your MX forks for better off-road riding. Not knowing your valving since it may have been altered, you can make these general changes to the STOCK valving.

 

BV: Remove apx 1/3 of the 30mm face shims (5). After the crossover shim, remove the odd shims in the HS stack. Shuffle the removed shims after your clamp shim (16?) which is probably too big. 14 would probably be better, but you don't want to buy any shims. The clamp shim is the single most important shim in your stack. Stack the shuffled shims in smallest to largest order to keep the stack the correct height.

 

I have no experience with the bleed stack, but the recommendation to "flip" it for more bleed is popular (for off-road) and makes sense to me. Friends have tried it and like it.

 

MV:

 

Comp: Remove one ore two of the 20mm face shims. These "float" on an 8mm dowel. If you remove only one, you will increase your float by apx .10mm, which you'll probably like for less harshness over trail junk. If you remove two (Turbo Dan makes a good point about the MV), you'll probably want to shorten your dowel by .10mm to avoid creating too much float. It's easier to stack another 10mm x.10mm/8mm id floating shim at the bottom of the floating shim stack, but you're desire is not to buy shims ($1 each.)

 

Reb: Leave stock.

 

This will give you a good starting point. Like most here, most end up tweaking their setups to optimize.

 

There are more important details to consider. I really recommend getting Race Tech's Motorcycle Suspension Bible to help you with this project. It explains a lot and has excellent, illustrated articles guiding you through all this.

 

Be sure to start with good seals/bushings, including the top and bottom cartridge seals or you'll end up with unwanted harshness.

 

Good luck!

 

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I resprung the bike to .43 and 4.7. I went back to my 4.9 in the shock other day. That made the forks noticeably improve. There still might be a little room for improvement yet. I also put all new linkage bolts in to get rid of the free play. That also helped.

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20 hours ago, Berm-Saw said:

I resprung the bike to .43 and 4.7. I went back to my 4.9 in the shock other day. That made the forks noticeably improve. There still might be a little room for improvement yet. I also put all new linkage bolts in to get rid of the free play. That also helped.

How much travel are you using after a good hard days ride?  O-ring or zip-ty on the fork?

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On 6/11/2017 at 1:59 PM, Berm-Saw said:

 

Is it possible to get my 06 crf250r forks and shock acceptable without buying shims? I'm 155 pounds. Don't ride mx, they are much to firm.

 

You cant get there from here! MX and Trail setups are very different and at all costs AVOID RT GOLD VALVES!

 

theDooger

Edited by theDogger

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