Fork Spring Installation

SteveG · Post by **SteveG** » Tue Sep 02, 2008 4:16 pm

Hello all -

I'm changing the fork oil for the first time in my 82 and the fork springs have a tighter wind on one end than the other.

They were installed with the tighter wind at the top.

I couldn't find anything in the shop manual or this site that specifies which way they should be installed. The picture in the manual isn't clear either as to which way they should go.

This leads to two questions: 1. Are the stock 82 fork springs progressively wound? and 2. Which way are they supposed to be installed? (I have bad experiences just reinstalling things the way they were).

Just for info, the springs both measure 22.5 inches.

Thanks in advance, Steve

Brian G · Post by **Brian G** » Tue Sep 02, 2008 4:26 pm

FWIW, aftermarket progressive springs are available for my BSA, and they stipulate that the more closely wound coils go on the lower end. Of course, that's next to no help to you at all, although I imagine the engineering realities behind that instruction would transcend marques. I'm sure someone else will call in soon....

Best Regards,
Brian

alimey4u2 · Post by **alimey4u2** » Wed Sep 03, 2008 4:29 am

A direct quote from EMS (Mike)

Technically, it does not matter which way you install the springs. They will work the same. Some claim with the tighter wound end down, there would be less "spring noise".

EMS · Post by **EMS** » Wed Sep 03, 2008 7:36 am

alimey4u2 · Post by **alimey4u2** » Fri Mar 13, 2009 11:43 am

Just bought these as another "upgrade" to my Prolink front end...

EMS · Post by **EMS** » Fri Mar 13, 2009 12:05 pm

In the middle of restoring a 1978 R100S, I took the fork springs out and they are installed tighter end on top.

cbxtacy · Post by **cbxtacy** » Fri Mar 13, 2009 12:09 pm

The tighter end on the bottom just might lower the cg. Losing 10lbs of ugly fat will definitely lower it. I could do that so easy, I just might start on a program to make the cg of all my bikes lower

. Should I lose 10lbs or make sure the tighter winds are on the bottom?

alimey4u2 · Post by **alimey4u2** » Fri Mar 13, 2009 1:01 pm

I seem to remember that all of the forks I have disassembled had the tighter coils at the top....

However, not too late to learn...

cbxtacy · Post by **cbxtacy** » Fri Mar 13, 2009 1:52 pm

I personally don't think that it makes any appreciable difference where the tighter winds are.

Don #6141 · Post by **Don #6141** » Fri Mar 13, 2009 3:48 pm

Since it really doesn't matter and since the tighter coils on one end make that end of the spring heavier, I would, install the heavy end down . . . . for obvious reasons

Don

EMS · Post by **EMS** » Fri Mar 13, 2009 4:45 pm

Lets get real anal here:

Assume the "looser" end of the spring compresses easier, means first when an impulse is transmitted through the front wheel.
If the loosely wound end is on the bottom, the spring compresses on the bottom first and leaves the upper part uncompressed or static. Turn the spring around and the upper part compresses first leaving the lower part of the spring static. Doesn't that mean, with a longer part static on the bottom, the unsprung weight is larger???

cbxtacy · Post by **cbxtacy** » Fri Mar 13, 2009 6:06 pm

I don't know but being the greedy capitalistic pig that I am, I'm taking bids from prolink owners to some serious product evaluation for them regarding front springs and they're proper installation for superior handling.

As you can see, I will push a stock (more or less) CBX to it's handling limits

. I will take a prolink CBX and run it with stock springs and with progressive (brand) springs. I will run them with the tight winds up and down. I will do it for $1000.00 (plus fuel used) and the results will be yours to peruse. And I will use the same track as in the photo. That's the cloverleaf intersection in NC at the intersection of I95 and Hwy87. Exit 46 on the interstate.

SteveG · Post by **SteveG** » Fri Mar 13, 2009 7:16 pm

Sweet pic, "George I am"

My main concern with the installation with tighter up or down was potential wear. I'm not the kind of guy that can feel those kind of differences in the suspension. But it sure did feel better with the fresh oil in it.

Can't wait to get it back on the road with the rebuilt shock and lubed bushings in the back

Steve

cbxtacy · Post by **cbxtacy** » Fri Mar 13, 2009 7:44 pm

I understand, I'm just looking for some money for a free trip back to NC. Just don't tell anyone incase they took my last post seriously (seriously, do you think anyone would actually do that? (if they do, I hope they don't read this post (and I need to quit posting what I'm thinking, it gets me into trouble))).

Rick Pope · Post by **Rick Pope** » Sat Mar 14, 2009 7:18 am

Progressive wound springs are installed w/ the tighter coils to the top because that's the heavy end, thus less unsprung weight. Or, at least that's the theory. I doubt I could tell the difference on a CBX.