Author Topic: GL1000 fork has no rebound spring?  (Read 1023 times)

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Offline Pelipen

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GL1000 fork has no rebound spring?
« on: July 20, 2018, 07:19:02 PM »
Hi,

I'm working on a set of GL1000 forks to swap onto a 550, and there is no rebound spring. Consulting CMSNL and Bike bandit, sure enough there is no rebound spring depicted on the GL1000 diagrams up through '79, but they did add it in '80 on the GL1100. Seems odd since even the '75 550 had one.

Has anyone added one when adapting these forks? Since I need shorter springs and tubes anyway, it seems like an easy addition if I account for it in the spring/tube length. Does the GL1100 spring fit? The 1000 rod is 18mm diameter, I can't find a spec on the 1100.

The rebound holes in the damping tube are only 1/2" from the top, but that shouldn't be an issue.

Offline slikwilli420

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Re: GL1000 fork has no rebound spring?
« Reply #1 on: July 20, 2018, 08:20:06 PM »
Stop reengineering things. The forks work quite well with a rebuild and fresh fluid. If you are doing the swap for better brakes and beefier forks then go all the way with straight rate springs and emulators. That is a performance enhancement.
All you gotta do is do what you gotta do.

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Offline seanbarney41

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Re: GL1000 fork has no rebound spring?
« Reply #2 on: July 20, 2018, 11:36:48 PM »
But god, he is right, they gotta be wayyyy too long for a 550
If it works good, it looks good...

Offline Pelipen

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Re: GL1000 fork has no rebound spring?
« Reply #3 on: July 21, 2018, 11:11:48 AM »
Stop reengineering things. The forks work quite well with a rebuild and fresh fluid. If you are doing the swap for better brakes and beefier forks then go all the way with straight rate springs and emulators. That is a performance enhancement.

Thanks. Yeah, that's the plan actually. I got the 550 as a non-running parts bike, and the fork stanchions are toast. I have some GL1000 forks with calipers that are in good shape, but too long. The GL are 2.6 inches longer than the 550 top to axle center, and I want them the same overall length. Since I'm doing custom length straight rate springs with emulators, stanchions, stainless lines, and new 16mm master; the absence of a rebound spring was one of those perplexing little things since other models of the same year, and the 1100 all had them. I always find it odd when there is an outlier, particularly when direct metal to metal is involved.

It's something of a resto-mod, with no cuts/welds, so it could be returned to stock if someone were so inclined, and I have all the original parts. Most of it is original, but with a ton of elbow grease added. Overall rake/trail/offset will mirror the 550, keeping the look of the 550 as much as I can, hence not running a CBR front end but with improvements where technology allows.