Fork tube wont come out

[SlowOldGuy]

Unless you drain it ALL out, blindly putting 424 ml (or cm^3, pick one) will result in different levels in each tube. 

Typically if you do this several times without actually measuring the level, you'll end up with over filled tubes.

What tools do you need?  Is there no PVC in Japan?  No 18mm bolts?  Fork tools are really simple to build.

DavidR.

[weymouth399]

I agree with David, unless you start with a completely dry system it probably won't be accurate. 

If you go with oil level it will be more consistant. 90mm-120 is a good starting point depending on weight and springs

And you can't be assuming that the cc. number is perfect. Yamaha couldn't even get the spring rate right for MOST riders, missed it by about 1/3 that's quite a bit. 

It's what feels good to you, those are generic numbers, for generic riders
Now you can dial it in to you and your riding style.

That's my 2 cents

Bob W

[SlowOldGuy]

In the end it worked sufficiently, 100% over beforehand as the front end was starting to bottom out!

Just an FYI.  The oil doesn't control whether or not the forks will bottom out.  The spring is in charge of the fork bottoming out.  The amount of oil in the tube has some effect on the overall spring rate, but it's primary job is to control the fork velocity, not the position.

DavidR.

[RichBaker]

In the end it worked sufficiently, 100% over beforehand as the front end was starting to bottom out!

Just an FYI.  The oil doesn't control whether or not the forks will bottom out.  The spring is in charge of the fork bottoming out.  The amount of oil in the tube has some effect on the overall spring rate, but it's primary job is to control the fork velocity, not the position.

DavidR.

But, if a lot of oil has leaked out, the air space/spring will be a lot bigger.... and that does contribute somewhat to bottoming resistance.

[SlowOldGuy]

Which is what I was referring to when I said "The amount of oil in the tube has some effect on the overall spring rate..."

Maybe I should have made it more clear.  I agree the air spring has an effect.  I think it is less of a contributor as oil leaks out. 

DavidR.

[fb747]

Yea i think there wasn't a whole lot of oil left in the forks, so not much damping going on just springs to soak up bumps. When i hit a big one it went to rock bottom.