Tool to disassemble 83 CR250R Showa forks

[SlowDinoDog]

It's a damper rod.... stuff a broomstick in there, push it hard against the ground and turn the ratchet...

I actually used a wood dowel for a bit of resistance with the impact gun...I prob hit it again with the impact gun after the springs were in and compressed which was giving it some resistance.

[RichieGoatGruff]

1st fork I took apart was an 81 XL250S, to install a terrykit... The instructions actually said to use a broomstick. Last, most "modern"d-rod forks I messed with were on my 90 FJ1200. Used a broomstick for them, too.

?

[DEATH_INC.]

On 3/6/2017 at 4:35 AM, Sofiedog said:

The '82/'83 manual discusses a 3 position adjustable compression damping feature.  However, I measured 14 indentation positions on mine which is consistent with what I had read in "GP's Classic Steel '83 CR250". Also, the adjustment feature looks different than the 3 position adjusters on the '82 forks. Look at the difference in the pic of the adjuster in the '83 Addendum diagram above. You can make out the little spring in the '83 addendum pic. I already have the forks back together but I think as you turn the adjusting screw on the bottom, it may affect the preload on the little spring which may affect how much fluid "leaks" out the top of the hollow nut?

The Service manual simply specifies 506 cc of ATF with a nominal level of 7.7 inches and a max level of 7.0 in and min level of 8.4 in. Manual states this will slightly stiffen or soften "fork spring effect" in second half of travel. The Service Information table in Chapter 3 says nominal front fork air pressure should be 0.0 psi but refers to a Service Limit of 21 psi. I don't know if thats for tuning or to recognize the pressure builds up during a race?

Anyway, I'm starting the tuning process with 5W Honda HP fork fluid at the lowest level of 8.4 in, the damping adjuster in the middle and 0.0 psig in the forks. I should have time to ride it this week to begin tuning.

Thx again for all the help.

Not sure if the CR was the same, but I had an '83 KX125 that had a similar unit, it was a 'pop off' valve to vent compression spikes, and the adjuster did simply adjust the preload on the spring. It had 4 positions.

I modded mine into a simple compression adjuster without the spring. I couldn't tell you if it was better or not, I was like 17 or so, it was a lot of years ago.

Fork air pressure? Yes it was normal to put a bit of air in them for extra springing back then, there simply wasn't the availability of aftermarket (or even oem optional) parts.

Some of the older guys here will remember the brief trend of removing the springs and running air only back in the late 70's too. It was about as successful as the newer air forks. ?

From memory most ATF was 10wt, which is what most damper rod forks specced.

Edited August 26, 2018 by DEATH_INC.