Progressive fork springs

[BuickWildCat]

Since I've got the XS11 running again it seems like there is a lot more dive when I hit the brakes than I remember. The fork fluid has been changed so I was wondering how well progressive fork springs work?
Thanks,
Mark

[crazy steve]

Progressive springs will help with that, but are you sure everything is right with your forks? Filling them with the right amount of oil is critical, did you try adjusting the preload, if you have air forks did you try more air?

You can also 'tune' the forks by changing fork oil weight and amount, I've had good luck with that.

[New2Me]

Progressive springs will help with that, but are you sure everything is right with your forks? Filling them with the right amount of oil is critical, did you try adjusting the preload, if you have air forks did you try more air?

You can also 'tune' the forks by changing fork oil weight and amount, I've had good luck with that.

I thought when the progressive springs are added you do not add air to your shocks? At least that is what someone on here told me last year. I never followed up with how much oil to add though.

[WSL91]

Since I've got the XS11 running again it seems like there is a lot more dive when I hit the brakes than I remember. The fork fluid has been changed so I was wondering how well progressive fork springs work?
Thanks,
Mark

I just made a set of spacers for my springs and they stopped the diving. I made them 3/4" as I have a Windjammer. I'd guess they are too stiff without the WJ

[crazy steve]

I thought when the progressive springs are added you do not add air to your shocks? At least that is what someone on here told me last year. I never followed up with how much oil to add though.

Yes, Progressive recommends that you not add air with their springs. But what I was trying to get across is that with some tuning, sometimes you can improve what you have for little or nothing. The air-assist forks aren't the best candidate for this as the springs are a bit soft, but using a bit thicker fork oil will help with dive.

I rebuilt a set of H air forks, swapped the springs for a set of early non-air springs and added 10cc of extra oil and they worked great...

[motoman]

Over the years of use, the orfices get larger(forks can get hot, and that is friction from the oil), so to compensate for that use a QUALITY 15w fork oil of your preference. Mine just happens to be Silcolene.

[jetmechmarty]

Heavier viscosity oil will slow them in compression rebound. More oil in the forks (less air space) will keep them from bottoming out.

[BigRed]

I bought progressive springs and rear springs & shocks, and I'm happy with them. I didn't put air in the forks with the progressives; just used the spacer length they recommended. They included the spacer material, I just had to cut it. My only disappointment is that I opted for HD springs for the rear because I'm a heavy guy, but I always have it on the lightest setting and find it stiff unless I have a passenger. I think the regular springs for the rear would have been good enough, and I could have stiffened them up when I had a passenger.

[jetmechmarty]

My only disappointment is that I opted for HD springs for the rear because I'm a heavy guy, but I always have it on the lightest setting and find it stiff unless I have a passenger. I think the regular springs for the rear would have been good enough, and I could have stiffened them up when I had a passenger.

I guess that shows how subjective this is. I put heavy duty springs on mine and it wasn't enough. (I'm 225#) It was hitting the exhaust or center stand in the turns. I now have 140/200 rate and that was the cure. Next time I'll go with straight rate as I did on the front and get a better ride.

[motoman]

Heavier viscosity oil will slow them in compression rebound. More oil in the forks (less air space) will keep them from bottoming out.

First part true as far as compensating for enlarged orfices...................second part, true to an extent. A hydraulic lock is more likely.

[jetmechmarty]

A hydraulic lock is more likely.

I'm using a Race-Tech tuning guide. I'm sure I 'm leaving enough space. You are right. No space=hydraulic lock

[Poprock]

I have a fairing. Set up using 15 wt fork oil. Had a rough ride, dive on braking. I swapped out the 15 wt to ATF @ 7# air. Ride is a lot smoother, dive is about the same. Tire inflation is crucial too. Running max sidewall number less 10%. May add 5% back. Full inflate with single rider made a lot of vibration. Lose 4# and the tire works better. Felt a little slippy on some turns yesterday, so I'll try a little more air next time out.

[motoman]

I have a fairing. Set up using 15 wt fork oil. Had a rough ride, dive on braking. I swapped out the 15 wt to ATF @ 7# air. Ride is a lot smoother, dive is about the same.

Imagine it would be.........ATF is NOT a dampening oil.......old school and works in a pinch...that's bout the extent of it.

[Poprock]

Motoman, I bow to your experience and expertise. No desire at all to jack this thread or to start another oil war. However I am curious about the molecular differences between a dampening oil and one that isn't. Can you help me out with that?

[Elevener]

I have heard the atf thing many times, some even mix it with MMO, to me specific fork oil just doesnt cost that much.