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Frodad78
1/21/2017 4:43pm
1/21/2017 4:43pm
Bike: 2005 YZ125
My issues are I have harshness in the initial stroke on the front forks. When I back off on the compression the harshness dissipates but now they are too damn soft on bigger hits. Blew my left hand of the bars today on a big landing, pretty sure its because I bottomed the front so hard my wrist over rotated.
How do I resolve this?
My issues are I have harshness in the initial stroke on the front forks. When I back off on the compression the harshness dissipates but now they are too damn soft on bigger hits. Blew my left hand of the bars today on a big landing, pretty sure its because I bottomed the front so hard my wrist over rotated.
How do I resolve this?
The Shop
The cheapest route, back your compression off and add about 15-20cc of oil to control the bottoming...
The fork oil is an idea to consider.
Can someone explain what exactly a revalve job does? For instance would an aftermarket product like Gold Valves help?
Thanks!
This was good advice. It's super easy to do and takes less than 30 min total. I would start with 10cc with the clickers at your current spot. Try that. You should feel less bottoming. Then add another 5cc at a time. I probably wouldn't add more than 20cc unless they were set up with really low oil level as 20cc is enough to make a good difference.
A "revalve" at it's simplest is to adjust the size, thickness, and number of shims that control how the oil flows in the forks. They are basically small thin washers that block oil from coming out of a small orifice. They bend more when the oil has more pressure against them.
It doesn't take much change of the shims to make a big change in the feel.
A revalve will also include setting the forks with recommended oil volume, but it is extremely common to "tune" that yourself by adding/removing up to 20cc or so.
"Gold valves" are a product that replaces the stock valves in the suspension. The "valves" are just the item that has the holes that oil flows through. The size, placement of the ports are a huge part of the feel and tuners have to learn how each new fork's stock valve affects the overall action. Race tech simplified this a little by producing and replacing stock valves with their own because that takes one huge variable out of the equation and makes it easier to find a good setting for a wide range of riders.
Also remember, any fairly large changes to the front will effect the back and fronts ability to work together.
1) Run SKF Green seals.
2) Run fresh OEM bushings (Inner and outer. The copper that is laid onto the non-teflon side wears off, causing the bushings to fit too loosely, which causes them tilt during fork action, causing stiction).
3) Run Honda HP 5 weight oil (It's the slipperiest stuff I've tried, and it's cheap to boot)
4) While you've got them apart to change the seals and stuff, check the tubes for runout. They are probably fine as it's hard to bend 'em, but it's a good thing to check off the list.
5) Be crazy OCD when reassembling the front end. The best method I've found for lining everything up is the method where you remove the fork caps and sink the forks through their travel with everything really loose so that the forks can fall into perfect parallel. In brief form, my method is to mount up the forks to the desired height using only the lower triple clamps to hold them in place. Install the wheel and axle tightening only the nut-side lug, and the nut. Then with everything else real loosey goosey (including a screw driver wedged into the non-nut fork lug to hold it open so it can slide on the axle, the upper triple clamp bolts loose and the steering nut loose so the upper clamps can swivel into alignment with the lower), I'll pull the caps out and sink the forks down till they bottom out and then start tightening things up. You want to take caution not to tweak the alignment as you tighten everything back up. For example, don't hold the wheel between your knees as you torque down the steering nut as this can twist everything up. Finally, I run pretty light torque values on my lower clamps to ensure there's not pinching going on, even lower than the manual suggests.
In my experience, these things pretty much solved my small bump harshness. Good luck.
So I added 10ml of oil to each fork and went a little stiffer on the compression. Had a good practice day yesterday, I was able to be way more aggressive and really slam through this set of rollers without feeling like the forks were mush so I think we made some progress here.
My only complaint now is that I'm still getting headshake on jump downsides and heavy braking. I like to get over the front of the bike so I think maybe dropping my tubes in the clamps might solve the issue. My Sag is right at 105.
Thanks again for all your input, It felt good to be hauling yesterday with confidence in the front end!
Pit Row
Thanks everyone for all your input and information!
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