Stiff front suspension - advice?

7 replies to this topic
  • ack1961

Posted April 30, 2012 - 05:51 AM


Hey all,
I have a few front fork questions on my '03 WR450.
I've recently lost quite a bit of weight, and when I was riding this weekend, I noticed that I can barely compress the front end at all. Another buddy rode it for a while (and now loves my WR450), but had the same complaint. We bled the air out and we tried to soften up the compression & rebound as much as possible, but it was still stiff as hell. Nothing we did helped very much. I'm running the stock spring setup.
I may have never noticed it being so stiff before because:
a. I'm novice rider who usually rides woods trails
b. we were riding hilly terrain with many jumps and water breaks
c. I weigh 50 lbs. less than the last time I rode it here (I now weigh 200) with the stock spring setup.

I figured that I'll try to perform the fork maintenance and change the oil. I watched a few videos posted recently and it doesn't look difficult at all. I'm ordering some parts (dust seal, main fork seal, bullet, seal driver, etc.) but I can't find in the Service manual which weight oil to use.
On page 5-35, it says "Recommended Oil - Suspension Oil 01".

I was going to add Yamalube 5W to my order, but I thought I'd check here first before I ordered the wrong weight.

Any advice would be welcomed, thanks.

  • Pooley

Posted April 30, 2012 - 08:19 AM


Best advice is to take it to a reputable suspension shop and have them set it up for your weight, riding style, typical terrain and desired preference of plushness. I'd also advise to spend the few extra bucks and bring the entire bike, not just the suspension to have them have everything set properly. Being that the bike is an 03, there may be some parts that have gotten worn out over time and you may not see the wearing, but a professional will.

Several years ago, I tried to do what you are suggesting and tune the totally stock suspension by changing the oil weight, level etc. I was still unhappy with how the bike performed and then went to a shop. It was light-years better than what I could accomplish myself. I ride a 01WR426 and weight about 185 lbs. The stock springs were acceptable for me (even up to 195 lbs) but the internal valving, shock oil wt and height definitely needed to be changed.

  • ack1961

Posted April 30, 2012 - 02:45 PM


anybody else know what the equivalent of "Suspension Oil 01" is?

  • msgbean

Posted April 30, 2012 - 03:14 PM


Suspension oil 01 is 5w.

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  • dustdogg

Posted April 30, 2012 - 04:08 PM


Did you remove the front wheel during this time? You may want to read the manual and and follow the procedure on the proper way to tighten up the forks and front wheel. If done incorrectly it can cause the forks to "bind" up which will cause it to feel as you described. Even if you didn't touch the wheel I would double check this. You may also want to verify fork oil level and set the clickers back to stock and go from there.

  • ack1961

Posted April 30, 2012 - 06:47 PM


Thanks for the replies.
I will definitely re-install the front wheel. I've read several threads today that echo how critical the front wheel re-assembly procedure is.

  • GuyGraham

Posted May 01, 2012 - 02:51 AM


Yamaha S01 is more like 2.5W
Motul 2.5W is 15centistokes, and Yamaha S01 is 15.6centistokes
Motul 5W is 18centistokes

see this

Edited by GuyGraham, May 01, 2012 - 02:55 AM.

  • MANIAC998

Posted May 01, 2012 - 03:17 AM


Nice find Guy!!! Thanks!!!


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