I hope someone may be able to offer some advice. I am working on a freinds '73 FL with hack of the same year. He purchased the combination new and it has always been hard on sidecar tire, but drives fine. The toe is measuring at 2 inches. I replaced a stripped front mount and the replacement parts are identical to the originals. The rear mount clamps to the swingarm, the swingarm bearings seem fine. I do not see any adjustment to the lower mounts for setting the toe in. Where there shims used in the mount between the ball and socket? The lean adjustment does not affect toe much if at all. Thanks in advance. Morry
Originally written by BoneYard on 11/19/2007 8:19 PM
I hope someone may be able to offer some advice. I am working on a freinds '73 FL with hack of the same year. He purchased the combination new and it has always been hard on sidecar tire, but drives fine. The toe is measuring at 2 inches. I replaced a stripped front mount and the replacement parts are identical to the originals. The rear mount clamps to the swingarm, the swingarm bearings seem fine. I do not see any adjustment to the lower mounts for setting the toe in. Where there shims used in the mount between the ball and socket? The lean adjustment does not affect toe much if at all. Thanks in advance. Morry
Hi.
2 inches is too much toe-in. It should be no more than 3/4" to 1". The early sidecar frames were not fitted with any place to mount the rear of the sidecar frame to the bike frame so they just clamped it to the swing arm. Your frame is an early one for a rigid frame. The clamp that you have was a changeover in the period when HD added the swing arm, sometime around 1958, IIRC. Later, afer 1979, they added a pad on the right rear and left rear of the frame for passenger pegs.
How are you checking your toe-in? I have two 10' pieces of 1-1/4" steel square tubing that are very straight and stiff. They have feet on each end and I place one against the front and rear wheel on the right side of the bike and the other one parallel with the sidecar wheel on the hack. The HD sidecar book shows where to take your measurement. I don't have my book handy now but I think the point is at the front of the front tire.
There should be some adjustment on the lower ball mounts. IIRC, the rear one will srew in and out. There are no shims for the balls. ALso, lean out should be no more than 1 degree. I usually set it at zero and my weight gives a bit of lean out.
Good luck.
I am measuring with a straight edge on the bikes rear tire as it is somewhat wider than the front and using a laser sighted off the sidecar tire. The HD book shows measuring at the back of rear tire and front of front tire. Front and rear mounts on the sidecar frame have the ball shaft press fit into the tubing, retained by 2 set screws into a grove on the shaft. I see from the parts book the '78 and later sidecars use a different rear mount with a threaded ball shaft and jam nut. I'm guessing I'll either have to modify the mounts or bend the sidecar frame to get toe to less than 1 inch. Seems odd that HD would engineer this way.
Originally written by BoneYard on 11/20/2007 6:32 AM
I am measuring with a straight edge on the bikes rear tire as it is somewhat wider than the front and using a laser sighted off the sidecar tire. The HD book shows measuring at the back of rear tire and front of front tire. Front and rear mounts on the sidecar frame have the ball shaft press fit into the tubing, retained by 2 set screws into a grove on the shaft. I see from the parts book the '78 and later sidecars use a different rear mount with a threaded ball shaft and jam nut. I'm guessing I'll either have to modify the mounts or bend the sidecar frame to get toe to less than 1 inch. Seems odd that HD would engineer this way.
Well, as I said, what you have there is really a rigid style sidecar frame which is being put on a swing arm bike. I would try to make some sort of threaded adapter to move the front of the sidecar out. If you have access to a machine shop and a welder, you could move the front outer thread mount out a ways to alleviate this condition.
It sounds like you are doing a good job measuring with the laser so you are very likely correct when you say that you are at two inches. Of course you are aware that this needs to be adjusted since it will cause undue tire wear and odd handling.
I've always found that Harley sidecars are pretty close on their adjusments when the year of the bike matches the era of the sidecar. You are correct, though, when you say that there should be some adjustment.
Let us know what you wind up with.
Good luck!
gnm109,
I appriciate the help. Interesting HD took 20 years to come up with a fix! Think they may have had some inventory to use up? I double checked my laser measuring with a couple of straight edges and came up the same. I'm going to try and make a cupped shim 3/16 inch thick and install it the front ball socket. There looks to be plenty of threads in the coupler to allow and still tighten. I did find an old post here where the guy removed the set screws and pulled the ball shaft out till the toe came in spec and relied on the "press fit" to hold in place, but I'm thinking that would be risky at best. Thanks again, Morry
Originally written by BoneYard on 11/20/2007 8:03 PM
gnm109,
I appriciate the help. Interesting HD took 20 years to come up with a fix! Think they may have had some inventory to use up? I double checked my laser measuring with a couple of straight edges and came up the same. I'm going to try and make a cupped shim 3/16 inch thick and install it the front ball socket. There looks to be plenty of threads in the coupler to allow and still tighten. I did find an old post here where the guy removed the set screws and pulled the ball shaft out till the toe came in spec and relied on the "press fit" to hold in place, but I'm thinking that would be risky at best. Thanks again, Morry
It sounds like you are on the right track. It would be OK to extend that front ball shaft if you could get it out. Some of them were set-screwed in and then plug-welded so they wouldn't move.
HD changed the rear mount on the model of sidecar frame right afer the one you have. It had the long extension cut off and the rear mount connected farther forward on the frame at the passener peg pad. That model had almost two inches of thread in the rear setoff mount.
Good luck!
Now there is an idea. I had it out to replace the outer nut that was stripped. If my shim isn't enough I sure could pull that shaft out far enough to get the correct toe and drill and plug weld it in place. I really appriciate the help. Thank you!
Originally written by BoneYard on 11/21/2007 7:44 PM
Now there is an idea. I had it out to replace the outer nut that was stripped. If my shim isn't enough I sure could pull that shaft out far enough to get the correct toe and drill and plug weld it in place. I really appriciate the help. Thank you!
Good. It's worth a try. Also, you could mock it up after you get it out and check your toe-in before you make your weld....or better yet weld something like a 3/8-16 nut on the outside of the tube and use a set screw to hold the shaft in place instead of welding it. As long as you have about three inches of the shaft sunk into the tube, you should have enough strength.
Let us now how it works out!
HApp Holidays.
