Fork springs dimensions

[Guest]

I just read in the manual that front spring length should be 421mm. I measured mine when I serviced the front forks and they are 500.5mm. I replaced the oil with 15w oil but I did not put any air in the forks and it still feels very soft. Are these springs Progressive? I thought they might be that is why I did not put any air in the forks.

[Hammered]

In my 750, the stock springs were 2 piece. A shorter upper and then the long lower. The Progressives I replaced mine with were a one piece and roughly the length you stated. Hope that helps.

[razooki]

In my 750, the stock springs were 2 piece. A shorter upper and then the long lower. The Progressives I replaced mine with were a one piece and roughly the length you stated. Hope that helps.

But I thought the progressive springs were supposed to be stiffer than stock. When I'm straddling the bike and apply the front brakes the bike dives about 3" and I think that is way too soft. If they are indeed progressive spring I'd hate to cut them. Maybe I'll try some air in them or a piece of pipe but I had a hard time putting on the top as it is.

[salty_monk]

The 850 has a soft spring that looks almost identical to a progressive spring as it's progressive wound & 1 piece.

Either cut it or replace with progressive.

Dan

[razooki]

Dan, I was trying to figure out if I have the stock springs or progressives or springs from another GS. The manual indicates a much shorter length for the springs (421mm stock vs. 500.5mm on mine) and I would hate to cut mine if they are indeed Progressive springs.

Raz

[crapwacker]

progressive springs are wound with closer coils on one end and factory ones usually are not. And they sometimes require a spacer. You can check their website for setup info for your forks

[Steve]

It's not so much a matter of how much it dives when you try pushing down on the forks, it's a matter of how much is sags when you put your weight on it. The difference between fully extended and loaded with your weight should not exceed 20-25% of the total travel. Most of our bikes have about 6 inches of fork travel, so you only want the front to sag about 1 to 1.5 inches. Adjust your preload with PVC pipe spacers to get that correct ride height.

.

[razooki]

It's not so much a matter of how much it dives when you try pushing down on the forks, it's a matter of how much is sags when you put your weight on it. The difference between fully extended and loaded with your weight should not exceed 20-25% of the total travel. Most of our bikes have about 6 inches of fork travel, so you only want the front to sag about 1 to 1.5 inches. Adjust your preload with PVC pipe spacers to get that correct ride height.

.

I'll try that I just hope that I can actually compress the springs and the pipe in order to screw in the top caps.

[Don-lo]

Did you try it with 10-15 psi? The bike really is made for that.

[razooki]

Did you try it with 10-15 psi? The bike really is made for that.

I did not because I thought that no air is needed if using Progressive springs.

[Don-lo]

I have progressive springs and I run air, works wonderfully.

[salty_monk]

I don't run air in the 1000's with progressives. The 850 also has a progressively wound stock spring so you're right - it is hard to tell!

Try upping the preload first, if you need to go much more than an inch above the top of the threads I would think about cutting some coils to stiffen the spring rate.

Dan