Changing fork oil on BMW airhead. Answer for Jeremy

Quick video response for Jeremy about how to drain fork oil out of a BMW airhead fork. I am using my /6 as an example.

[@ElBrooklyn1]

Thanks to you and Jeremy for hooking us up with this detailed explanation of both the fluid change, and the mechanics inside. Nice work!

[@minjobil]

well done Jeremy , clear and easy to understand...many thanks for going to the trouble of making the video.

[@HeikosGarage]

Jeremy was the guy I made the video for. My name is Heiko as in Heiko's Garage. Greetings

[@brucewharton869]

Excellent description of the process, thank you!

[@59jaguar]

Good job explaining this.

[@malcolmnash5850]

Thanks very much for your Tutorial.

[@chrispiatt2235]

Thank you kindly! I just replaced my seals and am now getting that rebound knock from the forks. What a ghastly noise. I'm afraid of the can of worms that awaits my trying to fix it.

[@HeikosGarage]

Just take the fork legs out and follow the manual. There are bumpers made out of a polymer material in the fork that will deteriorate over time.

[@arjundilip1543]

Legend!

[@bobdelaplage690]

Thx brother, my gs first generation has too much oil, ill suck it out from above i guess

[@mvooo]

Thank you for the video! What manual is that you have?

[@HeikosGarage]

It is the newest edition of the Hayness manual for my R90/6. Pretty good manual.

[@nramati]

Thanks to you, what would it take to change the fork's spring? I just got a new pair of progressive forks that I'd like to install. Would it include removing the handlebar- opening the upper fork bolt and just pulling out the old spring and inserting a new one instead?

[@HeikosGarage]

That is exactly right. Make sure you have the bike on the center stand. Remove the handlebar, take the two top plugs out, pull the springs out about half way, hold them there to let the oil drip off, put the new once in and reassemble.

[@nramati]

@@HeikosGarage Thanks! hope it will go smooth :)

[@frankmummolo7727]

After refilling with fork oil, I am assuming that the top fill plugs are still loose to allow air to escape, when Troy “bounce “ the forks to let air escape. Correct?

[@HeikosGarage]

I guess you could do that.

[@boxertwin1]

What number or weight fork oil do you use?

[@HeikosGarage]

I think the manual says 7 weight.

[@vespasandengines]

How to pump the fork? Can I keep it on the center stand and just pump by hand?

[@HeikosGarage]

Once you loosen the damper rod first you need to pull down on the fork slider. The pumping would be needed to get any trapped oil to come out the bottom as well. If you still have you front wheel installed you can just push down the fork while the bike sits on the center stand, just grab the front brake and push on your handle bar. I personally remove my front wheel and the fork brace. By doing that I can manipulate each fork leg individually.

[@Stefan123D]

Which fork oil would you recommend for my 1983 bmwr100?

[@HeikosGarage]

I would have to check a manual but most airhead BMW use 5 weight oil from factory. If that is to soft for you you can go up to 7wt or 10wt.

[@willyvegavega]

How much fork oil do I need to put in each fork??

[@HeikosGarage]

that depends on your model. Check this out bmwmotorcycletech.info/front-fork-oils-amounts.htm

[@nestcard]

Thanks for the video. The bottom threaded ring (#22 in your manual) is completely locked. What can I do to loose it and dissasemble? What do you suggest?

[@HeikosGarage]

The threaded ring inside the fork slider isn't really torqued against anything. It is held in place by a circlip. After removing the circlip it should spin right out.

[@nestcard]

@@HeikosGarage I removed the circlip, but the threaded ring its totally locked. Any idea to loose it?

[@HeikosGarage]

@@nestcard doesn't it have a set of grooves or holes? Try to screw it in farther, just a little bit. Inspect the threads maybe something is damaged in there. You could use a pick to clean the threads some. Washing it out with WD40 and compressed air might help too. I am assuming you are holding the fork leg on your hand and you can look in there.