R90/6 - Front Forks

[cris nitro]

Hi everyone;

I posted several months ago about replacing the fork springs on my R90/6. Well, I took the advice and bought a set of Progressive springs to replace the sacked out OEM's.

 

I have never had these apart and need advice on doing the job. I also want to replace the fork oil as it probably hasn't been changed in years. What weight oil and how much or what level?

 

Sorry, I do not have a manual for it.

Thnks for all your help.

Cris

[StuGotz]

Forks R90

 

bike on centerstand

 

remove caps from bottom of fork sliders

 

unscrew hex nuts 13mm wrench while holding the internal hex 4mm steady to prevent tube ends from turning.

 

unscrew caps at top of tubes (trip clamp) with pin wrench. (they may be stubborn, use caution not to gall pin holes.)

 

pull sliders down slightly to allow oil to escape.

 

screw bottom plugs back in and install bottom caps.

 

add 9 oz fork oil per slider from dealer ( if not avail, any hi temp, anti foam fork oil will work, I use old Shell aero4)

 

install top caps.

 

open beer.

 

MB>

 

OOPPS!.

 

Don't forget to install new springs while top caps out! You may have a pvc spacer that gets installed with new kit. This preloads the new spring to a diff rate than stock. If too stiff, then you may cut a slight amount off spacer each time for a preload adj.

 

 

 

 

 

[cris nitro]

MB;

Thanks for the help. I am currently busy over the next several weeks getting our clubs hare scramble track ready and will dive into the forks when it is over.

The instructions from Progressive describe the PVC spacer for the pre load. It seems pretty simple.

 

The hard part is going to be finding a pin wrench.

 

Cris

[SteveHebert]

I also clean the forks when doing this by using some diesel and working the forks up and down several times. Lot's of crud comes out. Very easy job with great results.

[StuGotz]

 

The hard part is going to be finding a pin wrench.

 

Cris

 

....these came in the original factory tool roll under the seat.

You DO have the tool roll, don't you?

 

You might find one at Bob's, A&S BMW, or fleabay online.

 

MB>

 

 

well lookie here:

 

http://www.cycleworks.net/index.php?main_page=product_info&products_id=350

 

good luck.

 

[cris nitro]

Great idea on flushing out the forks with diesel fuel. You do this with the forks still on the bike?

 

Yes, we do have the tool roll, I'll check for the pin wrench tonite! Thanks.

 

Cris

[cris nitro]

Well, I installed the new springs over the weekend along with fresh fork oil. Everything was fairly painless, except for when I "pulled down the sliders", they dropped down with a clunk about 1 inch and the damper rod disappeared into the bottom of the slider! No, problem, they pulled right back up into place and I could get the nut on it.

 

Wow, new bike! With the correct springs, the bike feels great, staying up in the stroke of the forks has transformed the handling.

 

Thanks for all the responses and help.

 

Cris

[Mighty Manfred]

My airhead came with Progressives up front. I've used their springs and shocks on a couple of Yamahas and installed a Progressive monoshock on the rear of my bike last Friday. Mucho improvement.