Well I just bought an older Dauntless subframe off Ebay to go on my '79 BMW R100T. It has two ball end type mounts (out of 4 points). All of the pictures I see on the web seem to have threads for clevis type mounts. Can anyone clue me into how the ball-joint mounts work?
I had a California sidecar many years ago that had ball and flower bottom mounts. The front mount slipped out more than once.
See this thread
http://www.sidecar.com/mbbs22/forums/thread-view.asp?tid=7715&mid=47420
The ball (and collet) mounts are used on sidecars with BMW /2 style connections for the lower mounts. URALs, Dneprs and CJs use this type of mount. Smaller versions of the ball and collet mounts were also used on the pre '89 CSC cars and early Motorvations.
The earlier Dauntless sub-frames used female threaded mount points so ball, clevis or eyebolts could be used. Their later varsions were more mount specific and eliminated this option.
Lonnie
Thanks Sidecarpete and Lonnie. That may certainly narrow down my side car choices 😉 At least I know I might have to have some work done to the subframe if I get a sidecar without collet mounts.
Strange that the shown tie screw is standard, on my MZ and many older rigs it allways had a lever head and a small leather belt to keep the tie screw in position.
Frankly I loved the ball fists they were very easy to handle and you did not have to hastle much with allignment when reassambling the rig.
Sven
If the balls are threaded on, then you can unthread them and we can supply either clevis or eye bolts to thread back in. These sub frames were often made of a specific aplication rather then a generic to the original owner may have wanted to go with the balls for some reason. In general I find the heim joints to be much easier to work with.
Jay G
DMC sidecars
www.dmcsidecars.com
866-638-1793
The ball for the rear mount is welded on. The front mount is a piece of steel with the ball machined on one end. The other end has female threads that, according to the previous owner, screw onto the front motor mount - I assume after removing the existing nut. It looks like grinding off the ball on the rear and drilling a hole for the threaded end of the heim joint. The front mount may need to be refabricated.
I just (as in last night) picked up a nice Velorex 563 I found used, local and at a great price. So my options at this point seem to be:
1. Modify the subframe mounts to use heim joints.
2. Trade subframes with someone who needs ball mounts.
3. Trade sidecars with some one who has a Ural/Dnepr/Chang but wants a Velorex. (Good luck with that!)
4. Sell the subframe and buy a new one.
Dauntless Motors breifly built sub frames this way for use with Ural sidecars. The sub frame did not provide an upper front mount rather it just had a frame clamp for the upper front mount. Current sub frames clamp to the cross tube between the down tubes right under the steering head, The sub frame then attatches to both engine mounting bolts on the right side of the bike. The rear sub frame attaches to both sides of the bike near the swing arm pivots, goes under the muffler on the right side and up the side of the bike attaching just ahead of the upper right rear shock mount.
Jay G
DMC sidecars
www.dmcsidecars.com
Dave,
The Velorex metric clevis bolts will not work with the normally used 5/8" heim joints as they are designed to slip over a 12mm eyebolt. 5/8" heims need a 3/4" clevis throat.
Other options could be:
Front upper mount as pictured we have here for $56. including shpg.
For a rear subframe mount a pad eye can be fabricated from 3/8" steel and welded to the subframe tube at the best distance for good triangulation of the Velorex mounts. A thin 1/2" washer will fill the small gap so you won't distort the sidecar clevis bolt when bolting it up.
Oh, forget about the castle nuts when mounting use 8.8 x 12mm nylocks for the strut connections. The castles are made to use once. They don't line up the same the second (or third) time around.
Lonnie
Just a point of view as engineer.
The ball head eliminates bending stresses and leaves only push pull stresses in the base of the ball.=> never ever weld a broken off ball to its base post.
While the heim joint takes off the bending stresses too, the stress is a shearing force in the base of the screw.
Steel has only 1/4 resistance against shear force than its pull/push resistance.
So go pretty big with the heim joint when you change the mountings.
Sven
