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2013 Kx250f Pro Action revalve

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Hi guys, after not being happy with my 13 kxf I decided to have it revalved. My initial problem was the front fork being too stiff, i could over jump anything, slam into jump faces and it wouldn't bottom which was great! But coming out of a corner it would hit the chop and skate all over the place. Same with braking bumps, I'd get a lot of feedback in the chassis rather than the wheel moving over the bumps.

My weight 190 pounds, maybe fast C rider? Hard to say as we have different classes over here.

Pro action shim stack for fork

4x .10x30

.10x24

.15x29

.15x27

.15x25

.15x23

.20x21

.15x19

They suggest I go from a .94 (stock spring) to a .99. I thought this was strange so instead went up one rate to a .96. The bike is almost worse. Still can't bottom it out and just doesn't handle the small chop, swapped bikes with a 14 crf250r and loved it. The Honda rider didn't know how I was able to ride the kxf.

Tried clicker settings, fork tube heights, sag settings and just can't find a good setting. Swapped the spring side fork on another 13 kx250f (so running my pro action valving with standard spring rate) and it helped a heap but still not what I believe it should be.

What direction should I go? Softer spring than stock? Get my tuner to lighten the valving? This thing just feels horrible.

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That stack is very light

Edited by karlace

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Dan, your going to have a hard time getting solid advice here because PA uses a unique design that even the most knowledgeable tuners that post here may not have experience with. I spent some years working with them, but it was pre SFF era, so I'll do the best I can.

Did they(Pro-Action franchise) install the system or you do it yourself(tuner not affiliated with PA)?

Do you know if there is a tapered base plate under the valving or a flat base like a stock valve?

Was there any modifications done to the midvalve stack or was it left stock?

Assuming the mid is still stock which is usual for PA, my concern is the .20x21 and if the base plate is tapered. The valving in a PA system can be thought of more like low speed than normal systems because the low flow port design limits the amount of flow at high/large shaft movements. If the stack is too stiff overall it can cross over into the built in flow control and create harshness, too soft and you could get excessive diving. Not too much different than a standard system, just more sensitive to smaller shim changes in my experience.

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Dan, your going to have a hard time getting solid advice here because PA uses a unique design that even the most knowledgeable tuners that post here may not have experience with. I spent some years working with them, but it was pre SFF era, so I'll do the best I can.

Did they(Pro-Action franchise) install the system or you do it yourself(tuner not affiliated with PA)?

Do you know if there is a tapered base plate under the valving or a flat base like a stock valve?

Was there any modifications done to the midvalve stack or was it left stock?

Assuming the mid is still stock which is usual for PA, my concern is the .20x21 and if the base plate is tapered. The valving in a PA system can be thought of more like low speed than normal systems because the low flow port design limits the amount of flow at high/large shaft movements. If the stack is too stiff overall it can cross over into the built in flow control and create harshness, too soft and you could get excessive diving. Not too much different than a standard system, just more sensitive to smaller shim changes in my

experience.

I had them installed by a pro action qualified tuner. It says remove beveled base plate which I'm assuming is the tapered one your talking about. Pretty sure mid valve was left stock

So what do you think my best option is here? I'm not really asking for shim changes as I do know having the PA valve is going to throw things out. But am I best to go back to stock and shim the standard valve to my liking? Or is the spring the issue here.

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I can only make assumptions having not tuned an SFF system with a PA valve, but I would think at 190lbs you shouldn't need to go any softer on the fork spring rate. Without the tapered/beveled baseplate the .15x19 acts as the clamp and I wonder if the .20x21 puts too much load on the rest of the stack causing the harshness. Maybe a .15x21 in its place would blend the stack better. I would also wonder if the oil level could be reduced a bit to help as usually PA runs on the higher end of oil levels to help with bottoming control.

If you have to keep throwing lighter springs at it to make it better, it would seem to me that is just a Band-Aid for a hydraulic issue. A PA system generally has very good low speed feel due to the light valving stack and most complaints(when received) centered around a wallowing/diving feel, but harshness was rarely a complaint. Obviously, this is a decision your PA tuner needs to make for you. My experience with PA has been harshness complaints are usually caused by a mechanical bind or valving that is too firm.

Edited by homo erectus

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I can only make assumptions having not tuned an SFF system with a PA valve, but I would think at 190lbs you shouldn't need to go any softer on the fork spring rate. Without the tapered/beveled baseplate the .15x19 acts as the clamp and I wonder if the .20x21 puts too much load on the rest of the stack causing the harshness. Maybe a .15x21 in its place would blend the stack better. I would also wonder if the oil level could be reduced a bit to help as usually PA runs on the higher end of oil levels to help with bottoming control.

If you have to keep throwing lighter springs at it to make it better, it would seem to me that is just a Band-Aid for a hydraulic issue. A PA system generally has very good low speed feel due to the light valving stack and most complaints(when received) centered around a wallowing/diving feel, but harshness was rarely a complaint. Obviously, this is a decision your PA tuner needs to make for you. My experience with PA has been harshness complaints are usually caused by a mechanical bind or valving that is too firm.

Ok cool, I think I'll go back to stock spring and I'll mention the .15x21 see what he has to say. I know everything's a compromise but I'd rather bottom it a few times and have a plush initial stroke.

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I can only make assumptions having not tuned an SFF system with a PA valve, but I would think at 190lbs you shouldn't need to go any softer on the fork spring rate. Without the tapered/beveled baseplate the .15x19 acts as the clamp and I wonder if the .20x21 puts too much load on the rest of the stack causing the harshness. Maybe a .15x21 in its place would blend the stack better. I would also wonder if the oil level could be reduced a bit to help as usually PA runs on the higher end of oil levels to help with bottoming control.

If you have to keep throwing lighter springs at it to make it better, it would seem to me that is just a Band-Aid for a hydraulic issue. A PA system generally has very good low speed feel due to the light valving stack and most complaints(when received) centered around a wallowing/diving feel, but harshness was rarely a complaint. Obviously, this is a decision your PA tuner needs to make for you. My experience with PA has been harshness complaints are usually caused by a mechanical bind or valving that is too firm.

 

I can't tell you how much I appreciate your info in this thread. I bought a bike from a friend who had the full boat three stage pkg from PA. Earlier I asked if anyone knew a "quality/trusted" tuner experienced with this system so I could get some adjustments. My bike suffers from harshness and excessive fork dive both. I got beat up by several and was told any tuner could fix things, was a dummy to even ask such a question. Maybe so but I thought good experience with the system would improve my odds. Your info tell me  my issue with the system is not just a mental problem. Thanks. :thumbsup:

Edited by YHGEORGE

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I can't tell you how much I appreciate your info in this thread. I bought a bike from a friend who had the full boat three stage pkg from PA. Earlier I asked if anyone knew a "quality/trusted" tuner experienced with this system so I could get some adjustments. My bike suffers from harshness and excessive fork dive both. I got beat up by several and was told any tuner could fix things, was a dummy to even ask such a question. Maybe so but I thought good experience with the system would improve my odds. Your info tell me my issue with the system is not just a mental problem. Thanks. :thumbsup:

George I'll let u know my findings hopefully this week. My bike doesn't dive at all. In fact I wish it did as I can't get a lot of front end tracktion.

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I can't tell you how much I appreciate your info in this thread. I bought a bike from a friend who had the full boat three stage pkg from PA. Earlier I asked if anyone knew a "quality/trusted" tuner experienced with this system so I could get some adjustments. My bike suffers from harshness and excessive fork dive both. I got beat up by several and was told any tuner could fix things, was a dummy to even ask such a question. Maybe so but I thought good experience with the system would improve my odds. Your info tell me  my issue with the system is not just a mental problem. Thanks. :thumbsup:

No problem! Also, I don't want to imply that other tuners can't do it, but experience with a certain type of flow theory goes a long way. Pro-Action doesn't offer training seminars and until recently they never sold their system retail, the only people with training in their systems would have had to owned and operated a franchise location.

I have never worked with a Gold Valve system so when customers come to me for revalve help, I recommend replacing the Gold Valve with a system I know I can make work or that they go to someone with experience tuning the Gold Valves. It would be too much testing to get it right if I wasn't going to work with them on a regular basis.

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George I'll let u know my findings hopefully this week. My bike doesn't dive at all. In fact I wish it did as I can't get a lot of front end tracktion.

Thank you but my bike is an older XR Honda, don't think your stuff would transfer. Really appreciate the thought though. :thumbsup:

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No problem! Also, I don't want to imply that other tuners can't do it, but experience with a certain type of flow theory goes a long way. Pro-Action doesn't offer training seminars and until recently they never sold their system retail, the only people with training in their systems would have had to owned and operated a franchise location.

I have never worked with a Gold Valve system so when customers come to me for revalve help, I recommend replacing the Gold Valve with a system I know I can make work or that they go to someone with experience tuning the Gold Valves. It would be too much testing to get it right if I wasn't going to work with them on a regular basis.

Expertise, integrity and a secure ego is a valuable combination. And appreciated by a consumer like me. :thumbsup:

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hello guys, me too have 13 kx250f but the sff 2° step don't like, the front fork being too stiff, how can i set compression  return air pressure for being  more soft and no get to limit ? thank you very much 

i'm 192  pounds

Edited by biasion

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You can change to a tyre with less feedback like a pirelli, Dunlop's for instance have a massive amount of feedback designed into them but they are also very sensitive to air pressure .5 psi on Dunlop's is the difference between fast and near unridable

Yz295

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The compression adjuster makes it softer

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