Odd spring in bottom of 77 Type 1 fork

Discuss all things 1970 & later Airheads right here.
Krauser4valve
Posts: 56
Joined: Thu Aug 26, 2010 8:37 am

Odd spring in bottom of 77 Type 1 fork

Post by Krauser4valve »

I took the bottom threaded cap off my right fork after draining the oil, something didn't seem right. I found this, anyone seen a spring added to the BOTTOM of a fork? The gunk in the bottom cap has a lot of silicone sealant in it, someone had added it to the threads. The spring is smaller in diameter than a normal BMW fork spring and is ~ 5 inches long. Image
Krauser4valve
Posts: 56
Joined: Thu Aug 26, 2010 8:37 am

Re: Odd spring in bottom of 77 Type 1 fork

Post by Krauser4valve »

Hmm, I took a look at Snowbum's site and I see a spring here that looks like the one I have. http://bmwmotorcycletech.info/ForkTool.jpg That looks like a later bike than mine though as it has electronic ignition :?
Kurt in S.A.
Posts: 1647
Joined: Tue Aug 03, 2010 12:08 pm

Re: Odd spring in bottom of 77 Type 1 fork

Post by Kurt in S.A. »

Possibly aftermarket anti-bottoming springs? They were highly touted at some point.

Kurt in S.A.
Krauser4valve
Posts: 56
Joined: Thu Aug 26, 2010 8:37 am

Re: Odd spring in bottom of 77 Type 1 fork

Post by Krauser4valve »

Thanks, I had no idea. I googled "anti-bottoming springs bmw" and found a reference to Luftmeister selling them.
lrz
Posts: 342
Joined: Tue Aug 03, 2010 8:01 am

Re: Odd spring in bottom of 77 Type 1 fork

Post by lrz »

I had/have those in my '77.

After the rebuild, including new bottom "bumpers", I was informed that it should be either the springs or the bumpers, not both.

Mine handles well with both...
Krauser4valve
Posts: 56
Joined: Thu Aug 26, 2010 8:37 am

Re: Odd spring in bottom of 77 Type 1 fork

Post by Krauser4valve »

I think I'm going to ditch the springs and order new bumpers and washers. With the Progressive Suspension springs on top it is just way too stiff to ride around here with our lousy roads. BMW HD springs might be the next step.
Duane Ausherman
Posts: 6008
Joined: Thu Aug 12, 2010 12:39 pm
Location: Galt California
Contact:

Re: Odd spring in bottom of 77 Type 1 fork

Post by Duane Ausherman »

I remember those and they are just more snake oil.

It doesn't matter where you put the spring, top or bottom, the result is the same. You just have a longer spring.

So much was made of the added spring that it became outside of physics. People want magic and are willing to pay for it.

Yes, there is a valid question of ride height and spring compression. However, most of the attempts to fix the forks ignored the most important thing, the alignment. If the forks have stiction, then the rest is a waste of time and energy.

So many riders keep to the idea that what worked on forks on other bikes will work on the much stiffer BMW fork. Wrong. If they have stiction, the bike won't handle as well as it possibly can. It may even have a wobble. If you aren't deathly afraid of a wobble, then you haven't been in one.

Ask anyone who has been in a tank slapper at 80 mph if they want to do that again.
Ask the Indians what happens when you don't control immigration.
User avatar
mattcfish
Posts: 754
Joined: Mon Aug 02, 2010 11:18 pm

Re: Odd spring in bottom of 77 Type 1 fork

Post by mattcfish »

The biggest advantage I can see to the springs is that they don't desolve
Bellingham, WA USA
1975 BMW R90/6
1975 BMW 2002
1971 VW Westfalia
1985 VW Vanagon
http://advrider.com/index.php?threads/b ... s.1074183/
Krauser4valve
Posts: 56
Joined: Thu Aug 26, 2010 8:37 am

Re: Odd spring in bottom of 77 Type 1 fork

Post by Krauser4valve »

After re-assembling the fork with the stock bumpers and washers replaced, I inserted the axle to check on the alignment. It doesn't line up without applying a decent amount of force to the left lower vertically. I could be nuts, but I'd swear that the left fork side looks to be longer from the bottom of the RS fairing. If I measure each fork tube distance between the top and lower clamp, the left fork tube is .020" shorter. Time to make a adjustment?
lrz
Posts: 342
Joined: Tue Aug 03, 2010 8:01 am

Re: Odd spring in bottom of 77 Type 1 fork

Post by lrz »

When I refreshed the forks myself, I didn't have that problem.

When a MaxBMW tech replaced fork tubes after a deer collision, I experienced that exactly. Also, the front end did not track right at all.

Though I finally had them make it right I don't know 100% what the issue was, but was told that the wiper rings had been destroyed during the initial repair.(?)
Post Reply