Picked up a 78 r100/7 in great condition. The steering seems stiff so I want to check the tree bearings. I removed the handlebars and clamps, and removed the center 36mm bolt. Question is do I need to remove both 36mm fork bolts? Can't seem to loosen either of them with the wrench I'm using. It looks like I do, as I can't loosen the slotted nut that holds down the triple tree to the bearing. Thanks
Yes, the 36s have to come off, they sandwich the upper stamped triple clamp to the fork tubes. When I use the tool kit tool I help it along with a brass/lead hammer. ( Depending on your experience with using a hammer I would suggest tank removal beforehand. ) Once you get the upper triple clamp off you'll see the steering bearing adjustment nuts. Once those are removed you'll be staring at the upper bearing. The grease gets old and stiff and makes the head bearing feel brinelled. Remove the old grease, look for vertical divets in the bearing races and if none found, regrease and reassemble. If your fork action was nice and smooth, I've found it helpful to mark the fork tubes to lower triple relationship with a sharpie to retain the original alignment. The adjustment nuts tend to be a bit tricky because you think you got the perfect amount of play until the crown nut is torqued and the bearing tighten up, it'll take a bit of patience to get it right.
Stiff and smooth, good, Stiff and notchy, bad. Disconnect any steering dampener if fitted and see how it feels. On the brinelling, Wipe the races with a solvent soaked rag to clean them...like really clean, and dry with a clean towel. You are looking for an even shine all the way around the race. If you see vertical lines, clean some more and look again (especially if the bike had been sitting). if you still see lines, replace the bearings. They don't cost a whole lot but you need some tools. Google Ed Korn.
The flat, stamped 36mm toolkit wrench is one of the better tools for removing the top fork nuts-- it grips well and can be tapped with a hammer. If you get a 36mm socket, you'll need to carefully grind off the chamfer on the front of the socket-- it'll grip the thin top nuts much better. --Bill
I got a 36mm but its from a kawasaki tool kit. Maybe I'll re try that. Just need more leverage on it. Def should remove that tank as I could see the wrench an or hammer slipping and smashing the tank.
I think I have that same wrench, a Kawasaki box end wrench with the tappered handle. Tool Kit size. About 6 or 7 inches long? I use mine all the time. I currently keep it in the on board tool kit but have to remove it because the Heyco/BMW wrench also does the swing arm sockets and having one wrench for two functions makes more Tool Kit sense. The Kawasaki wrench is a much better tool. It is forged steel. Not stamped. Most of the Heyco/BMW wrenches are forged but not the one we are talking about. I also carry a small sized hammer and use it as an impact tool often on the bike. It's really too small for the exhaust nuts and my OEM exhaust wrench. So if there should, unlikely, be trouble with these on the road and should luckily actually have that wrench I'd need a big rock. We'd really like to know when you find out, is it greasing time or you have to change bearings?
A small deadblow happer is nice. You can saw off the handle and use it as a "thumper" hammer. You can also buy a handleless thunper, woodworkers use them. http://www.highlandwoodworking.com/yellowthumperdeadblowmallet.aspx
Chris Harris of Affordablebeemerservice.com has an excellent set of tutorials on YouTube that discusses all the steps involved in removing and replacing the steering head bearings on BMW airheads. Unfortunately, for newbies, he did not show the removal of the inner bearing races from the steering head. He used a MIG welder, and did this off camera. The factory way to remove the inner races is to use the Kukko internal puller 21-6 ($160), and counter-stay 22-2 (also $160), both available from samstagsales.com. These tools make it foolproof, and you won't damage the frame as is possible with other methods. These tools are pricey, but still less than the labor cost at your nearest BMW dealer.
When the point is reached in the disassembly to inspect the races and they look like they have to be replaced, cycleworks.net sells some reasonably priced tools for the job:http://www.cycleworks.net/index.php?main_page=product_info&cPath=29_33_50&products_id=64 I repacked the bearings in my /7 about six months ago without a full tear down. It is possible that the grease has gotten hard and the bearings and races are ok. If not, the tool set should make replacing the races much easier. Good luck!
When I got my R100RT the steering was stiff and notchy. After tear down and clean up (the old grease was like wax) the 34 year old bearings and races looked brand new. Steering head bearings should last a lifetime, that is unless someone over tightened them and damaged the races. TINK
That just isn't so TINK. I think BMW recommends changing them every 25K? If you are super touchy about your front end setup and I am, it doesn't take much longer than that to notch steering head bearings. I have changed countless sets of notched steering head bearings that did not have dried grease in them. With use they notch. Wheelies and hard braking notch them sooner but . . . . Steering head bearings that last for ever? The steering damper on K75's somehow makes them last WAY longer than usual. I have never looked into it but they do last longer on K75's from what I have seen.
