75 R90/6 Fork Fixes

Just picked up a 75 R90/6, it has a lot of touring type things on it like a windjammer, hard bags, crash bars, top case, etc.. I was just wondering if this would cause the fork to feel packed down or sacked out. The bike has 56k on it and maybe the springs are just tired im not sure. What is the accepted route to go when trying to firm up the fork. Thanks Greg

Springs do eventually wear out.

I've got a '76 vintage, with Hannigan fairing. It exhibited similar characteristics. This past winter, along with installing an Omega charging system, I did some work on the forks. I installed a set of Progressive springs, and used 10wt oil, along with new fork seals and whatever slider bushings needed replacement. After the maintenance I also installed a fork brace. For the re-installation of the fork legs I first slid them into the triple-clamp and snugged up the top retainer, with the wheel and axle installed but not tight, along with the front brake caliper. Then I took the bike off the centerstand and proceeded to bounce the front end, then snugged the clamps on the lower triple-clamp. More bouncing and snugged up the fender mound. More bouncing and then installed the fork brace. Finally snugged up the axle. Now the fork works, doesn't sag, and responds well. It also made the bike's handling improve.

Keep in mind that the bike was known for a very pronounced dive under braking. It will likely be more than any other brand bike you have ridden before.

Having said that, does the bike just seem to be nose down at rest or only under braking?

If it's only under braking you can try changing the fork oil. IIRC the oil used to be about 5 wt and if you go to a 15 wt oil it will stiffen up the ride quite a bit and will be the cheapest thing you could do for it. If the bike just seems to be nose down you could change out the springs then add a higher viscosity oil.

bluecycle3 said:

Just picked up a 75 R90/6, it has a lot of touring type things on it like a windjammer, hard bags, crash bars, top case, etc.. I was just wondering if this would cause the fork to feel packed down or sacked out. The bike has 56k on it and maybe the springs are just tired im not sure. What is the accepted route to go when trying to firm up the fork. Thanks Greg

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Replace thefork springs with an aftermarket Hevy Duty spring. OME springs weak.I had a 74 /6 replaced the fork springs. I now hav e an 83 rt. Replaced the springs.much less dive on hard breaking.