spring ??'s



13 replies to this topic
  • kozmic

Posted April 01, 2002 - 06:53 AM

#1

Can anyone suggest what rear spring (and/or fronts for that matter) I should use with my shock? And what strengh the '01 yzf426 comes with stock? And how to tell what spring you got? I bought my bike about 6 mo. used and am beginning to wonder if the guy before me changed it to a softer one. Here's why I ask....The lowest I can set my race sag (and still get about 1" of static sag) is about 6.25". I have it set to ~5.25" right now with about .25" of static sag.

I weigh about 190 (185 on a good day). I hear folks say that the stock spring set up should be good for up to about 180 lbs? I don't see how this is possible, unless of course as stated before, I have a less than stock strengh spring and don't know it. The guy I bought it from was obviously a "I don't jump" kind-of-guy and weighed at least 10-20 lbs more than me. He also had all the comp clickers out about 14-16 clicks. even a very moderate jump would bottom at least the front for me until I realized they were set so soft.

  • skthom2320

Posted April 01, 2002 - 09:25 AM

#2

I am not sure what the stock rear is but I weigh the same as you do. I recently had my suspension done by JM Racing and they went to the next stiffer spring - a 5.6.

I was able to set the sag with the stock spring though. If you want a stocker I'll be happy to sell you mine cheap. Send me a PM. Since you're in Houston I'll be glad to meet you at 3 Palms or Splendora...

[ April 01, 2002: Message edited by: skthom2320 ]

[ April 01, 2002: Message edited by: skthom2320 ]

  • bassr_#186

Posted April 01, 2002 - 09:55 AM

#3

I weigh around 190 and use the stock spring. I set the race sag at 90 mm and the static sag is still within spec.

  • Lackey-92

Posted April 01, 2002 - 10:58 PM

#4

Hi,

The stock spring on th '01 426 is a 5.4 and if your spring is stock it will be silver with a yellow mark on the end coil. If the spring is any other color then it's a guess as to what weight it is. A good rule of thumb on your spring weight is this.

Set your rider sag to 100mm (Approx 4.0") then check your static sag. If the bike has less than 17mm (.75") then the spring is too soft. If you have more than 25mm (1.0") then the spring is too stiff. It is opposite of what you would think but that physics.

I run a 5.6 on mine and I weight 200 with my gear. My suspension is re-valved though.

  • kozmic

Posted April 01, 2002 - 11:36 AM

#5

The spring is in fact silver, but I don't know about the yellow mark? I'll have to check. It is a Racetech spring. Says "Racetech" clear as day in white lettering and has what I believe to be a product number or something?

Did Yahama use Racetech springs stock?

I was trying to get to about 100mm race sag but if I go where past about 140mm~150mm my static sag goes to nothing (like 6.5mm). The position of the low comp clicker shouldn't have any affect, right?

I'm really thinking that this isn't the stock spring. I think the guy I bought it from must have tried to make an mx bike a trail bike and didn't like the outcome?

  • txthumper

Posted April 01, 2002 - 12:12 PM

#6

wanna sell the spring..sounds like its softer than a 5.4, maybe a 5.0..thats what i need in the woods..i weigh 165..let me know

  • txthumper

Posted April 01, 2002 - 12:13 PM

#7

oh yeah..i have a set of stock fork springs..46kg, they have maybe 10 minutes on them...you need them?

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  • motoman393

Posted April 01, 2002 - 03:41 PM

#8

If it is a Race Tech spring then look at the last 2 digits on # stamped on the shock spring! If your spring's last 2 digits are "52" then you have a 5.2 spring etc etc this should give you a good basepoint. I am 168lbs and run 5.2 and .44

  • John_Lorenz

Posted April 01, 2002 - 03:46 PM

#9

:D I took my stock one off and placed a spring in from a Hum-Vi

Think thats why my back is hurtin :)

  • Shawn_Mc

Posted April 01, 2002 - 03:56 PM

#10

I took my stuff to Enzo and Ross set me up with a 5.6 in the rear and .47's in the front. Made a massive differece. I read in a mag somewhere though that the suspension guy at Pro Circuit set up a 250F with a 5.7 spring. The mag editors wondered about that, then marveled at the ride. Makes me wonder...Going a tad stiffer requires less initial loan resulting in a softer initial stroke, but im curious about the rising rate aspect.

  • kozmic

Posted April 02, 2002 - 06:28 AM

#11

I wrote the number down, but as luck would have it, I'm on the fifth floor at work and the paper I wrote it down on is in my truck :) . I'll get it at lunch (soon). But I could have sworn that the last two digits of the number were 56. Does this mean it's a 5.6? And again, did Yamaha use Race Tech springs stock? Anyone?

Here's how I measure my race sag - maybe I'm doing something wrong....

I thread a piece of thin rope through the rear axle from the chain side. Then tie a loop in the rope at the end on the muffler side then loop the the rope around the muffler tip. With the bike on the stand I pull the string up to the top of the chain side number plate. Then while holding that mark with my thumb measure the distance from there to where the rope hits the axle. Then I take the bike off the stand and stand on the footpegs. While barely leaning the grip against the wall, I again hold the rope up to the same place - the top of the chain side number plate - and hold that mark with my thumb again. Then very carefully get off the bike - while still holding the mark - and again measure from the mark on the rope to where the rope hits the axle. And I was very careful to make sure that the rope was securely on the muffler tip and didn't move between measurements.

So basically, I measuring the distance from the top of the chain side number plate to the top of the rear axle hole while on the stand with the rear wheel off the groud and then again off the stand with me on the bike. Same with the static sag 'cept without me on the bike for the off-the-stand measurement.

I can measure the distance while on the stand w/o the rope but this is the only way I can measure it while on the bike by myself.

Can someone confirm that this is correct or not?

Thanks!

[ April 02, 2002: Message edited by: kozmic ]

  • kozmic

Posted April 03, 2002 - 03:38 AM

#12

Ok, here's what the spring says: RACE TECH 622856. Anyone know if this is the stock spring?

  • BK14MX

Posted April 03, 2002 - 06:31 PM

#13

Thats not a stock spring. The only idea I have for you is to get a second person to make the measurements while your on the bike. I recently found out how much the correct sag will help the bike handle. Also, I have a race tech spring on my bike too, one thing I did notice, and this is where I made my mistake, it's taller than an OEM spring. I just put the collar back where it was before, which caused the sag to be all jacked up. Get another person to help with the measurements, it will make it much easier to figure out whats going on, good luck.

  • kozmic

Posted April 04, 2002 - 04:31 AM

#14

Thanks....that at least tells me it has been changed :) . Maybe the guy I bougt it from did the same thing. I'll check it out.





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