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Main Area => General GS500 Discussion => Topic started by: noiseguy on February 16, 2011, 01:55:48 PM

Title: Stock front forks: new springs, oil, damper rod modifications?
Post by: noiseguy on February 16, 2011, 01:55:48 PM
Finally sick of front end dive on my stock 1990 GS forks. Have new Sonic springs on order, .80 kg/mm (I'm 170#, want them for street use.)

Questions:

What oil should I run in this? 10W, 15W?  

I've seen posts on plugging the hole controlling the rebound rate on the damper rod, as a way to compensate for the stiffer springs (increases rebound damping) Anyone tried this with improved results? Or leave alone for now?

Any opinions appreciated.
Title: Re: Stock front forks: new springs, oil, damper rod modifications?
Post by: RichDesmond on February 16, 2011, 03:14:09 PM
I'd go with 15w.
Title: Re: Stock front forks: new springs, oil, damper rod modifications?
Post by: centuryghost on February 16, 2011, 03:46:20 PM
Rich sent me this when I got mine:

"
Instructions should be in the box. The same info is on the site at:

http://www.sonicsprings.com/catalog/damper_rod_forks_tech_article.php

Use 15w oil, set the height to 115mm.

Here's how to set sag:

http://www.sonicsprings.com/catalog/setting_sag_street_tech_article.php

Thanks,
Rich"

BTW, the person who posted before me is the same Rich!  :cheers:
Title: Re: Stock front forks: new springs, oil, damper rod modifications?
Post by: Pelikan on February 16, 2011, 04:54:00 PM
Yeah, I just recently got the .85s and Rich recommended 15w.  I wouldn't tool around with the damper unless you have to.
Title: Re: Stock front forks: new springs, oil, damper rod modifications?
Post by: noiseguy on February 16, 2011, 08:26:38 PM
Coolio. I'll start there and see where it goes.