Anyone try 3 250f clutch springs for softer lever pull?


57 replies to this topic
  • Bandit9

Posted November 09, 2013 - 06:17 PM

#21

Ok, I rode today with the 3 250f clutch springs. 3 Thumbs Up! It worked great. The pull got a lot lighter after a few miles of ride time. I did get it to slip, but not very much. In fact, it was a good slip. I would rip it wide effing open coming out of a corner or attacking a loose dirt/rock hill climb, and it would slip just enough to get all the power down to the ground. Very similar to how an Auto Clutch slips. It only slipped when I was WFO or very close to it. I really liked this a lot on the 450. Felt like I could get uber aggressive. I had ZERO issues lifting the front end, in fact, I found it way more controllable to wheelie. Navajo's springs didn't come in in time, but he rode mine and came back with a smile on his face.

If you don't ride real aggressive, you probably won't ever get it to slip. I'm talking like A rider hauling ass aggressive.

The only negatives I can see for me will be an annual clutch pack replacement. Which is cheap and easy to do. I'll take it. The other negative is how it will do in the mountains on real long climbs where you are in the upper revs for a while. Which for me, will not be very often. However when I do hit the mountains, I will still just replace the clutch pack after if I need to bc the benefit far out weighs the negative.

This mod is very cheap, $20, and takes just 5 minutes to do. Ya'll should try it.

Install tip, take a marker and number the clutch cover bolts before removing. I pretended it was a clock face and numbered them as they would appear on a clock. They are all different lengths, so good luck if you skip this. Also, just put the 250f springs in a triad pattern, basically every other one. The 250F springs are shorter than the 450f springs, so don't be alarmed.

Any questions, fire away.

  • Bandit9

Posted November 09, 2013 - 06:41 PM

#22

It was 2009 YZ250F clutch springs and the torque spec on both the springs and the clutch cover bolts is 10ft lbs. You do need to remove the rear brake lever bolt to get clearance for the 7 o'clock bolt.

  • Bandit9

Posted November 13, 2013 - 09:17 AM

#23

Correction, it is 10nm/7.2ft lbs torque spec on the cover bolts and spring bolts. Sorry.

  • KJ790

Posted November 13, 2013 - 09:40 AM

#24

I don't think that putting 250F springs in the 450 is a wise choice. YZ250F springs are not really a lighter spring rate than the 450 springs, as the 250F uses 5 springs in the clutch while the 450 uses 6 springs. The biggest difference is in the length of the springs. The 450 springs have a free length of 50mm while the 250F springs have a free length of 35.7mm. This means when you put the 250F springs in your clutch they are barely preloaded at all. Uneven spring pressure like this could possibly cause clutch problems in the long run.



  • Bandit9

Posted November 13, 2013 - 08:37 PM

#25

What type of problems? I mean it is a given that the clutch plates and disc will wear faster by doing this. Which isn't a big deal to me. Hell, some racers replace that after every race. So what exactly will happen? The only thing that would be a big issue to me would be premature notching on the basket, since the basket is pricey.

  • Bandit9

Posted November 13, 2013 - 08:39 PM

#26

LOL, I guess if the basket gets notched, then you put in a Core EXP and none of this would matter anymore.....

  • KJ790

Posted November 14, 2013 - 05:36 AM

#27

Uneven clutch spring pressure can cause the pressure plate to warp, which will make the clutch act funny and chatter during use. It's not the end of the world, you would just have to buy a new pressure plate, but it is inconvenient when it happens. I have had it happen to me twice and had to buy a new pressure plate each time to fix the problems.



  • Bandit9

Posted November 14, 2013 - 06:50 AM

#28

Thanks for replying. So how did you warp your pressure plate twice? Were you using shorter springs like I am? I've heard of warped steel plates, but never a warped pressure plate.

I just looked it up and the OEM pressure plate is $40. So for me the trade off is still good. I may just go ahead and buy spare pressure plate, discs, and steel plates. Keep it in my spares box so if anything happens I could just replace it at the truck and keep riding.

Edited by Bandit9, November 14, 2013 - 06:58 AM.


  • redhurricane

Posted November 14, 2013 - 07:29 AM

#29

LOL, I guess if the basket gets notched, then you put in a Core EXP and none of this would matter anymore.....


Unless they are TOAST like mine were, file them smooth and call it good.

  • Bandit9

Posted November 14, 2013 - 08:28 AM

#30

Unless they are TOAST like mine were, file them smooth and call it good.


No doubt.

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  • KJ790

Posted November 14, 2013 - 09:48 AM

#31

Thanks for replying. So how did you warp your pressure plate twice? Were you using shorter springs like I am? I've heard of warped steel plates, but never a warped pressure plate.

I just looked it up and the OEM pressure plate is $40. So for me the trade off is still good. I may just go ahead and buy spare pressure plate, discs, and steel plates. Keep it in my spares box so if anything happens I could just replace it at the truck and keep riding.

The first time I had it happen I was purposely mixing stock springs with heavy duty springs on a modified engine to prevent clutch slippage without making the lever way harder to pull. It worked great for a little while, then the clutch started acting funny. It would not work smoothly when I tried to ease it out, it would grab and pulsate and it became almost impossible to slip it slightly coming out of corners without it chattering and pulsating. When I pulled it apart everything looked good, but the pressure plate looked a little funny where it contacts the clutch plates. I bought a new pressure plate and my problems went away.

 

The second time was with a different bike and was from using cheap aftermarket springs. When I started to have the same symptoms as before I decided to pull the clutch apart and measure the clutch spring rate and found that they were not even, some of the springs were substantially lighter than others. I think some of them started to sack out while others held their original spring rate. Again I replaced the pressure plate and went with new springs and never had an issue again.


Edited by KJ790, November 14, 2013 - 09:49 AM.


  • Bandit9

Posted November 14, 2013 - 11:42 AM

#32

I wonder where I could find some different springs? I would like to try some springs that are the same the length, but with a lighter spring rate.

I know Rekluse has a few different spring rates for adjusting the auto clutch engagement rate. I'll give them a call and see what they say.

Maybe Cannon Racecraft could make some cheaply.

  • Bandit9

Posted November 15, 2013 - 10:55 AM

#33

Cannon Racecraft said they can do it with no problem, for $80 a set of a 6 springs.

  • funt

Posted November 15, 2013 - 12:58 PM

#34

I'd get an MSR raptor or something and keep the stock clutch springs.



  • Bandit9

Posted November 15, 2013 - 03:10 PM

#35

The whole point of changing springs is so not to mess with the pull ratio, which changing the perch/lever or drilling holes in stocker does.

Edited by Bandit9, November 15, 2013 - 03:10 PM.


  • funt

Posted November 15, 2013 - 03:42 PM

#36

If I can shift from neutral to first without clunking and there's a nice bit of free play, that's enough pull for me.



  • Bandit9

Posted November 15, 2013 - 03:58 PM

#37

I'm not worried about shifting from N to 1st. I use the clutch on just about every corner and everywhere else too. It isn't that big of deal, I'm just seeing what is possible through just doing spring changes.

Edited by Bandit9, November 15, 2013 - 03:59 PM.


  • Bandit9

Posted November 16, 2013 - 06:01 AM

#38

This looks interesting

http://www.onelightclutch.com/

  • woods-rider

Posted November 20, 2013 - 08:17 AM

#39

This looks interesting

http://www.onelightclutch.com/

 

 

That does look interesting, but they don't really say how it works which would make it hard to justify the high price.



  • grayracer513

Posted November 20, 2013 - 10:34 AM

#40

The Rekluse springs that are changed out for the purpose of adjusting the engagement point of their setups are not pressure plate springs usable in a normal clutch.

 

Install a Z-Start Pro in your WR and you'll have a pinky finger clutch pull.  Of course, you won't really ever have to pull it, but... :excuseme:






 
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