Front end question

[Guest]

New, rebuilt E model fork tubes on my 1000C. They are stiff to the point where if I put 25 psi in them they don't compress at all when I grab the front brake. I'm still running the single caliper. Without air, they're still stiff but they give a little and they ride low. Are these characteristics of progressive rate replacement springs or do i have some binding. Everything is straight and the bike corners better than it did with the other forks. These forks are the ones I bought from fatkid89704 back in May. This is my third set of GS forks that I've rebuilt, so I'm pretty sure I didn't screw them up. My thought is that the new seals are sticking, I bought the Leakproof seals instead of the Suzuki seals.

[BassCliff]

Spring has sprung...

Mr. JATO,

I probably should not say anything for fear of embarrassing myself, but it's late and nobody's watching. 8-[

As I understand Progressive springs, they are stiffer than stock. But they are supposed to soak up the little bumps and really get stiff on the bigger bumps, so as not to bottom out.

So you've installed Progressive springs in your forks? I have a pair waiting to be installed in my bike. When I do that I'm planning to never use air again, especially that much. Right now I run about 15psi. On my bike the max allowable is 35psi but the manual never gives numbers over 10 when setting up the suspension.

Perhaps you need longer spacers (instead of air) to adjust the preload? I asked questions about new Progressive springs in this thread and got some great information. Maybe it will help.

Thank you for your indulgence,

BassCliff

[Billyboy]

NO AIR WITH PROGRESSIVES.

And 25 is 11 lbs too much for standard stock springs.

[JATO]

I installed a new set of forks that were suspected of having progressives. The purpose of the new forks is to run dual front brakes. My problem is they're stiff even without air. The bike goes down the road straight so I'm pretty sure they're not bent.

[JATO]

I let the air out. I'll take it for a test tomorrow.

Edit: I weigh 200 lbs and with me sitting on the bike, the front end has has 1/16 of an inch of "squat." If I forcefully push on the bars while holding the front brake, I can get maybe 2 inches and then it rebounds. BTW, the bike is a 1978 GS1000 that I'm trying to put a 79 E model front end on.

[SqDancerLynn1]

Something doesn't sound right, I would start by checking what they used for spacers with the prog spring ?? If they used to original spacers it would make for a VERY stiff front end

[JATO]

I did the reseal job and all of the spacers appeared to be stock. I don't know the history behind these forks so I'm in the dark here. Also, I have 20 weight fork oil in them if that helps the diagnosis any.

Under the bike's own weight, it sits lower in the front then it did with the other forks and I can't get them to "stretch" any. They've almost got to be binding internally. Come to think of it, when I did put them on, the lowers gradually angled towards each other and rotating the uppers in the triple tree didn't change this. The other forks didn't do this.

[JATO]

BTT for the day crew's review.

[t3rmin]

If you really have Progressive springs, it sounds like they're working as expected but you have too much preload and might want a ligher oil. You want around an inch of sag with you on the bike, I believe. Too much preload would give it an overly stiff feeling, as would a heavy oil.

Exactly how long are your preload spacers?

[hp1000s]

The stock pre-load spacers are at least 3X's too long...I'd hate to be the one trying to compress all that on top of Progressive springs.

[chef1366]

I tend to agree with the preload. Unless you are binding.
If the preload is that strong how in the world did you get your fork caps back on?

[JATO]

The caps went on fine, I think they're binding. It's going to have to wait until the weekend for me to do anything about it, job schedule and all.

[JATO]

Problem solved. It was a combination of sticky seals and bent metering rods. So, I took the right lower off of the "new" forks and put it on my "old" forks. Now I have a straight, perfectly functioning set of pseudo E forks. Now I need to true up my front rim, I think I over did it when I tightened the spokes. I know I didn't hit anything.

[JATO]

Wobbling front rim fixed too. Spent about an hour tightening and loosening spokes until it ran true.