changing shock oil R100/7
I am new to the Forum and new to BMW ownership. I am doing a cosmetic restoration on a 1980 R100/7. I read a post about changing shock oil that said the shock spring must be released to allow for pushing up the rod that releases the shock oil at the bottom. I suggests the spring will "pop up" a couple of inches. It looks to me like the top attachment nut must be taken out to accomplish this. My question is do I need to remove the top shock nut to change the oil, and if so, how difficult is it to get the sping back into the shock?
You only need to remove the whole nut assembly if you're going to thae the forks apart. Just remove the fill plug, then the bottom nuts and wave washers. The fork lowers should fall down and the oil will drain out. Do this on the centerstand and use two flat sided pans, one on each side. You can leave the front wheel on. When the forks are drained, pull down on the front of the bike so that the "studs" come through the holes and put on the wave washers and nuts, one side at a time.
If the studs don't want to come through the holes you can use a pin punch to stick into the center of the stud and pull it over and into the hole. You'll note that the recess is machined for a 4mm. allen wrench. You may have to use that to get the nut to tighten. Do not tighten the nut too much. They can break off!
Thanks for the info. I took off the lower keeper nut and washer but nothing happened. Do I tap on the inside of the shock to get the lower part to drop or does the fluid come from around the threaded stud rod?
The 4mm socket screw is pushed into the fork to release the fluid. Getting a Clymers or Haynes manual would be a prudent choice for maintenance. I found using the older 265 ml refill quantity worked better for my old forks. I also filled my forks with Mercon V ATF fluid. Unscrewing the fork caps helps the fluid drain.
This is kind of hard to describe without pictures. All the above advice is good. The manuals are not perfect, but they help.
You have the bike up on the centerstand with maybe a board underneath of it so the front wheel is an inch or two off the ground?
You were able to get the nuts and the washers off of the small threaded rod at the very bottom of the forks (underneath the rubber caps)?
You have the filler caps off the top (but not the big cap that clamps the fork tube to the upper triple plate)?
If you wiggle the front wheel and pull down a little, the whole assembly should slide down the tubes a half inch or so. When that happens, the oil can drain out the holes.
If it won't slide down and the bike is new to you, you might consider removing the wheel, axle and fender brace so you can work each fork independently. Kind of expanding the simple change the fork oil job, but again, if the bike is new to you, gives you a chance to clean up the pin that holds the brake caliper, maybe take the lower part of the fork completely off the tube. Chances are, if regular Maint hasn't been done, the bottom of the fork is going to be filled with crud and you can't clean it unless you remove it.
Again, with the nuts removed, the isn't anything keeping the lower parts from sliding down the tubes, so if it doesn't, might need to do some additional inspection.
Thank you all for your considerate help. I do have a manual, but it does lack certain instructions. I realized in the middle of the night that it should have been obvious to me that taking off both sides was the only way the fork(s) would drop. Duh! Today should be more successful. Thanks again
(you might want to consider using different vocabulary in the future. "shocks" typically refers to the boingers in back. "forks" refers to the boingers up front. carry on.)