Cheap, inexpensive, useful, ...hydraulic jacks...
for use in servicing your BMW Airhead motorcycle
© Copyright 2020, R. Fleischer
Above are two inexpensive 'bottle jacks'. Note my 12 inch tall 'machinists square' in the center, and the ruler below. These are in the photo to give you an idea of size. Jack tops (sometimes called anvils) are often the versatile types that screw-down into the jack pistons and those jack pistons are shown with jack pressure released, that is, down. Another one of my jacks, not shown here, is very similar, the adaptor top made from a piece of iron pipe, cut with a hacksaw, to make a half round longwise. Nicer than the bent metal type in the right side of the above photo; and is described in this article. The jack on the left side has a top I made from aluminum stock.
Below is a photo of my small scissors jack. It is rated at 2 tons. I find this small jack quite useful. I have made a curved cradle for the top of this jack, as shown. As on my other jacks, the curved cradle is rotatable. This jack cost a bit more than the bottle jack type I discuss in this article; still, this scissors type was fairly cheap.
To make very useful jacks for all sorts of work on your BMW motorcycles, I suggest you purchase a small scissors jack as shown, and also purchase the smallest, cheapest, hydraulic bottle jack at your nearest auto-parts store, WalMart, etc. For the best versatility get a short one that has a screw top that you can extend upwards.
The packaging boxes typically list approximately 6 inches of possible lift movement. In actuality, for the one's I have seen, the hydraulic piston will move a bit under 5 inches. These jacks sell for $15 or so, and every one I have seen is made in China. I have yet to see any of them leak or otherwise fail.
Unscrew the top threaded part to its upper limit, if it has such a threaded top part (which I do find useful).
Obtain a piece, maybe 4 inches long, of iron pipe (but, read the entire article here...you might want another material or size). I suggest the inside diameter of that pipe to be such that after you cut it, it fits under and slightly around, but not at all snugly, at any frame or swing arm round tubing areas that you might use it at. In particular, have the piece of pipe, as cut, fit the 'crossover' at the forward area of YOUR Airhead's swing arm.
Note that most Monoshock Airheads have a larger diameter crossover, and perhaps you will want to measure one, and make your jack fit universally.
Cut the pipe LENGTHWISE to make two halves. I usually do this in the middle, or with a slight bias towards one side; there is no need to have your adaptor be so large as to grip the bike crossover, etc. Clean-up one of these halves ...that means clean up and round the sharp edges. Weld or bolt, or?....that half to the top of the jack, keeping the top threaded part of the jack cooled with a wrapped water-soaked rag if welding.....weld such that the curved piece will be SQUARELY welded to the top. Again...be SURE it is squarely welded, and don't just tack weld it, weld it all around.
Some jacks can be drilled and tapped and an aluminum pipe or other piece used, so read onwards. Further, some jacks have their tops include a rotatable anvil unit, and perhaps even on a threaded shaft that can be adjusted for height. I find those jacks by far the most versatile. I suggest you do NOT weld your adaptor to the jack anvil if the anvil does not rotate.
Just one use for these types of jacks would be to jack up the round tubing rear cross-member, to enable you to move the rear tire a bit off the floor. Very handy when wanting to rotate the rear tire such as to rotate the engine when setting valves, ........and many other chores.
You may need a sturdy piece of wood to have the jack high enough. I have found a 1 inch piece of plywood, and a piece of 4 x 6, to be just right for most Airheads. On one of these many jacks I have modified, I put holes in the corners to enable sturdy mounting of the jack to studs sticking up from various pieces of wood. Let your imagination work for you. I also have small pieces of wood to use at the top of my jacks for various purposes.
Some may prefer to use a taller jack to begin with, with a larger base to the jack (or, make a base). Be cautious, because if the minimum jack height is too tall, you may have troubles using your jack at all.
The first photo contains two relatively recently-made jacks. Neither one has the iron pipe as described, because after some begging, I gave away my last of the iron pipe ones.
The first photo's jack on the left has a undercut (spot faced depression, hidden from view here) under the milled aluminum piece, and a central hole, and I drilled and tapped the jack top piece. It is way overly-fancy. The jack on the right was one I made up in about 10 minutes, crude, and functional. If you make up some sort of jack like these, consider if you need a much larger base, perhaps of heavy metal or maybe a foot square piece of plywood, if so, perhaps bolt the jack to it.
You can also sometimes use a large conventional low floor jack, etc., depending on your bike. For a late model Airhead with the exhaust collector chamber, that chamber is going to prevent you from using the frame cross piece. A jack under the exhaust collector, with a piece of wood, works fine. Many of you have conventional or low-boy large size jacks, if they do not work for you on the motorcycles you own, why not consider the jacks in this article!
One item not shown is that I have pieces of wood that fit the top of these jacks ...and make the top of the jack a flat surface ...so the jack can be used at places like the oil pan, etc, without damaging any fins, etc.
04/13/2003: Add .htm title; clarifications.
09/06/2003: Add photo of two types of these jacks; minor text changes.
02/25/2005: Final editing and release.
10/04/2012: Add QR code; add language button; update Google Ad-Sense code; move photo to top, edit article slightly.
2013: Remove language button script, was causing problems with some browsers. Update article.
03/05/2016: Metacodes and layout.
07/16/2016: Minor updates on metacodes, scripts, layout, fonts.
07/16/2018: Reduce excessive html, fonts, colors. Add the scissors jack photo and clarify some details. Add 10pxl margins.
12/11/2019: Clean up. Clarify some details, 12/02/2020.
© Copyright 2020, R. Fleischer
Return to Technical Articles LIST Page
Return to HomePage
Last check/edit: Monday, December 07, 2020