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Respring or revalve? (too soft)

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The bike is a 2006 Yamaha WR450. My weight is 162 lb, and I ride tight woods and open quad trail, anything from wide open sandy whoops to rutted, root-infested single track. I am a B level rider.

The bike has been revalved by Race Tech with Gold Valves front and rear.

The fork and shock springs are stock as confirmed by the RT tuner:

Fork = .452 kg

Shock = 5.28 kg

The problem is the suspension is too soft for the faster sections and jumps. I am bottoming occasionally but the bike is staying too far down in the stroke. Even on relatively easy terrain, I am using all but 2" on the fork travel. This is ok for the really tight trails but not good for the faster trails, whoops and jumps.

In an attempt to fix this with minimal expense, I have changed from 5wt to 7wt and now 10wt. I also increased the oil height to the maximum of 95mm air chamber. Clickers and high speed settings on shock are where one more click stiffer and I am deflecting too much on the roots.

According to the Shop Manual, the stock springs are on the fringe of being too soft for my weight. Current springs are for 154 lb rider. I'm 162.

I want more bottoming resistence but I don't want it at the expense of harshness in the initial travel. Would it be better to revalve or change to the stiffer springs?

If I change to stiffer springs, I would do the following:

Forks: 0.45 to 0.47

Shock: 5.28 to 5.5

The stiffer rate springs are closer to what is recommended for my weight in the Shop Manual.

Edited by Navaho6

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Well, its easy to tell if the springs are right for you or not, just check the fork sag. Your baseline should be 60mm of rider sag in the forks, +/- 2mm.

It sounds to me like you're on the right track, spring seems to be a bit soft and by increasing the oil level to compensate, you are generating mid-stroke harshness. You should have at least 20mm of anti-bottoming resistance at the bottom of your travel. I check this by flat landing jumps to see how far down the fork collapsed. If you bottom, thats not good, if you have 40mm of room, thats not good either. Stick a zip tie on the tube and have the upper part of the fork push it around, thats a easy way to get some good readings.

Oil level is measured in CC, so what I usually do is dump all the oil out and measure, write down that number. Then compare to OE level and add or subtract in CC's. Its very hard to accurately measure oil level without using the CC method.

Hope that puts you down the right path. Sadly I don't know enough about WR's to give you a specific oil height to go by. :bonk:

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