35mm fork damper mods

[Gavin Housh]

Ok Wildman, you asked for this. These are specs for the pre 75 35mm forks with stock seven in. travel. Remove damper rods and get out as much oil as possible, as braze welding will be done and welding on oil soaked metal is not good. Once you have the dampers in hand have a welder braze shut one side of the through hole in the bottom of the damper rod. After the metal cools you need to file and then sand smooth the filled area so that it's as if the hole never was there. Now find a friend with a milling machine and a 1/16 in. drill bit. Clamp the damper rod in a vise that is parallel to the table on the mill. Find the center of the remaining hole in the bottom. Now move up the rod 1/2 in. and drill through one side of the rod. Do not drill through both sides. Now move up another 1/2 in. and drill again. What the finished rod will look like is the stock bigger hole in the bottom of the rod with six to eight 1/16 in. holes on 1/2 in. centers on one side of the rod only. Start with six holes. Use 15 wt. Bel-Ray fork oil. I've tried the Spectro and it does not give the same feel. Almost forgot high up on the rod are two holes of different diameter, drill the smaller of the two so that they both are the same size. Again no holes go through both sides of the rod. I'm useing eight holes with 15 wt Bel-Ray with the oil just covering the tops of the dampers when looking in from the top with the forks fully extended. These mods work for riders from 160-180 pounds. Heavyer riders will need less than eight holes. Lighter riders may use 10 wt. Remember all the bottom holes are related to compression and the two top holes are rebound. I also used these specs on my ribbed 8 in. forks on my 75 250. If I had it to do over I would leave the rebound holes alone on the 75 forks. Rebound was a bit to fast for my taste. Good luck.

[john durrill]

Gavin,
 would you post this in the library for us?
it will fit in the files section and help folks 6 months from now.
Thanks ,
John D.

[wildman]

I used to make a simular mod on old Maico forks, so i've brazed and filed damper rods before, but I had no idea where to start here. Thanks for the info. Wildman

1975 250 Cross Country, 1974 175 Jackpiner, 1975 125

[Lew Mayer]

Oh no! I have to take my forks apart again?

Lew Mayer