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yz 426 revalving

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So i have been riding my bike lately and getting used to it and so far I absolutely love the handling.I really feel a big difference since i rebuilt the shock. But of course i want to make it better.

I am 6' 2" and i weigh about 178 with my gear on. I am a low B level rider and i only ride motocross, i dont do any trail riding at all. Personally i dont mind feed back though my forks and i like to feel any ground difference under my front tire. For my shock not so much, as i have already felt it through my forks.

I have looked at the mx tech spring calculator and i am spot on with the fork springs. Are there any valving issues that i can address here though? I have seen some post of the 2001 blowing through the stroke. I dont really have a bottoming issue on G outs or anything involing jumps of any size, unless i do something stupid of course. They do seem to dive a little too much when i get on the brakes hard though. I dont have a problem with pushing or sliding out in flat or sandy corners or anything though, and it rarely tucks. what can i do to fix the diving? I want to try and do this myself if i can. Adjustments arent fixing this either.

As for the fork the spring calculator says the stock shock spring is a 5.5, and it recomends a 5.3. Ive looked at the 2000 and 2002 models and they have a 5.0 stock spring. Did yamaha try to do something different with the 2001 model? Personally i dont feel its too stiff, but i dont really have experience with anything else so. Is the valving too stiff for me also? Are there any issues i can address? It doesnt really squat that much durng hard acceleration but sometimes it doesnt seem like the traction is all that great(during acceleration). I have the sag at 102 mm to compensate a bit but that causes me to run wide on turns sometimes, its not TOO much of an issue but i would love it to be a non issue. I have pretty good traction over dips and around flat turns and such though. Those are the only complaints i have about the rear shock so far.

So for actually valving. For the forks i have the base valve and the midvalve, right? And the shock has the low speed and high speed rebound and compresstion? Ive done some searching and it seems that removing shims lessens the stacks effect and adding shims increases the effect of that stacks particular function. And the size of the shims work the same way. Is this right?

Sorry for the long post and the lack of understanding, but i really want to learn how to do this. I know it sounds dumb but im kinda excited to learn how to do something like this, ive learned a bunch from this site and i would love to learn more. Thanks for any help guys, i really appreciate anything you can tell me.

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That particular motor had a bigger effect on the front when breaking due to the amount of engine breaking it provided. If it were me I would try running a little less float or stiffer mid comp valving. This will help hold the front up alittle more. I am not sure what the float is on that bike.

As far as your shock, when are you having tracktion problems? If it is general traction problems, I would lower your ridder sag to 105 and see if that helps. If not try softning the high speed (hex head) to let the rear settle in a little more. If you are having trouble on chopy corner exits, try speeding your rebound alittle to help the rear wheel keep from packing and in contact with the ground better. If these things dont work, you may have to soften the lowspeed portion the your comp stack.

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That link doesnt work, it says that it cant find the page. But thanks for the help so far though.

So i found the stock fork stacks here on TT after some googling.

(10) 24mm X .1mm

(1) 22mm X .15mm

(1) 20mm X .15mm

(1) 18mm X .15mm

(1) 16mm X .15mm

(1) 14mm X .15mm

(1) 13mm X .15mm

(1) 12mm X .15mm

(1) 11mm X .25mm

(3) 18mm X .5mm

(1) 11mm X .3mm

(1) 24mm X .12mm

So, since i want to make my mid valving a bit stiffer i could replace the 18mm with another 20mm? Is this right? I want to try small changes at first.

And for the shock I will try the adjustments on the high speed. I kind of have trouble with tuning my shock, its like i cant tell a difference sometimes except for sag adjustment.

thanks for the help though, i really appreciate it

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That link doesnt work, it says that it cant find the page. But thanks for the help so far though.

So i found the stock fork stacks here on TT after some googling.

(10) 24mm X .1mm

(1) 22mm X .15mm

(1) 20mm X .15mm

(1) 18mm X .15mm

(1) 16mm X .15mm

(1) 14mm X .15mm

(1) 13mm X .15mm

(1) 12mm X .15mm

(1) 11mm X .25mm

(3) 18mm X .5mm

(1) 11mm X .3mm

(1) 24mm X .12mm

So, since i want to make my mid valving a bit stiffer i could replace the 18mm with another 20mm? Is this right? I want to try small changes at first.

And for the shock I will try the adjustments on the high speed. I kind of have trouble with tuning my shock, its like i cant tell a difference sometimes except for sag adjustment.

thanks for the help though, i really appreciate it

No I wouldn't go that route because, it will make it stiffer but its marganal that far down in the stack. Your stack starts at the 24's and ends with the 11. The shims listed under the 11 are inactive or noncontributing to the compression stack. Sence you are wanting to stiffen as a hole, I would either add a 24 or pull the 11 off the bottom. The 24 will have a greater effect as it is right at the piston face and will make your stack more rigged not only at the begining but also all the way through. If you pull the 11 you will be changing your clamp to a 12. That will make the stack stiffer all the way through but with a less effect than adding a face shim. Now to your float. I am not exactly sure what the float is on this bike, but looking at the stack you have posted, it looks to be pretty big. You will have to measure it and see what you have for sure. Assemble all of your shims that sit on the collor to the piston and measure them and the piston together. Then add your collor and any shims that sit under it along with your compression shims and subtracks from your first measurement and the difference is your float setting.If you add a 24 you will be opening your float even more witch will not be productive so you will need to adjust your float to compensate for that. To do this, you will need to shorten your collar by .1 using the adjustment shims under it. Or if you decide to pull the 11 off the bottom, you will have to lengthen the collar to compensate or your float will tighten up quite a bit. either way you will stiffen up your compression.

Btw, your stack doesn't match what suspension network has listed. Go here http://www.suspensionnetwork.com/ and set up a free acount so you can see what they have. Your best bet is just to pull it apart and measure it all out for yourself that way you know it's right.

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So, i assume that making the entire stack stiffer will make the valving stiffer? But yes, i was riding today and i can really feel the forks drop when the engine breaking starts. I like the engine breaking on it, but the dive has to go. So i was saying replace the first 18 with a 20, but that seems to be counter prodictive since the float will close up. I want to take my forks apart and check this out myself, but its in the middle of riding season and i only have one pair of forks. On the other hand i have 3 shocks that i can play with.

So the general concept is making the valving stack stiffer will make the vavling stiffer. And vice versa. Is this right?

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