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Building a Harley softail rig

When I get a bright idea I have found from experience that I need to try and discredit the idea and only after a great deal of pondering should I do it, that said.      Moving the car wheel back by extending the swingarm may not be such a good idea as it probably will alter the dynamic behavior of the car when extreme braking is involved with dire consequences,  teeter tottering the bikes back wheel off the ground at worst and reducing traction at best. NO NO!!!!!!!! So back to the drawing board and perish that thought. When I harden the bikes underframe around the CG which is just behind the back motor mount I am also creating a new hard point for the car's front mount which in turn will reduce front wheel load when braking if I simply re attach the car there. With both upper and lower struts at the back I would simply lengthen the struts and pivot them backwards from the bike and they really carry the load at the back. So my Heim joint etc is really just a positioner and one end of the toe in adjustment. In keeping with that thought I also will bring the towing wheel or rocker tandem wheels off the same hard point and to the other side. I am thinking of using 4.80X8 class D wheels with a 900 lb load rating @ 65mph. By incorporating a free rocker tandem I would be using the trailing wheel as a suspension to reduce shock on the front wheel. I would harden the frame by incorporating a piece of 5/16" 1045 cold rolled steel to fit behind the engine mount from tube to tube with threaded holes for the tandem mount bracket bolts. I would just bolt the bracket on under the bike and jack it up to fit the rocker and wheels on the pivot at the bracket. I could then run the front wheel alongside the primary case and and the back wheel on the inside of the rocker putting it behind the clutch bulge. I would have a 3 part system that would go in the car trunk and probably not take 15 mins to install or to remove on the bike.  With the bracket removed I would have the full ground clearance under the bike Now to ponder that solution.  later Chuck

The more I think about it the more I like the little walking beam axle to carry the bike with a car tire on the tub side. I feel it would be an asymetric beam  but I still need to decide if I need to give the advantage forward or to the back wheel. I feel that if I gave the advantage to the front it would help set the suspension up for potholes and reduce the shock load on each tire as well I would use a beam approx 20" tween axles jack it up and put the beam on The car side would only carry its normal weight and using the electric trim I could even level it out side to side. I would still stay with a 3 piece system for easy stowing. I already have 4 ways on the rig so I would just let those leds run off the battery or put in a trailer hookup on the bike. Because my bike has low ground clearance I do not see how to leave the mounting bracket on when riding so that is an unavoidable chore . Then not having to deal with a trailer is also a very big blessing and a good trade off. Not counting my labor its also only about $100 out for wheels/hitch etc. Other materials I either have or will scrounge or trade for KACHING.  Maybe I can find a way to leave the bracket on and have enough ground clearance making it a 2 part deal. I have a width limit the rig has to stay between the car's mirrors so thats the booger. Later Chuck

I have been working on the towing contraption and have made great strides. This is new territory I believe and because I have a heavy rig it has to be strong. My concept is that the bike has to be carried and the side car wheel really will just be doing its normal job and carry the kerb side weight. Keeping in mind that I like things that are lightly stressed when carrying their normal load I started at the wheels. I chose 2  480X8". C class wheels with a combined rating  of 1400 lbs + Then I chose to go with a walking beam tandem as it is a no shock system that yet gives a very smooth ride.  I used existing hard points on the left side of the bike frame to attach s 2"X2" subframe the projected forward tp the front motor mount. I then made a crossmember that bolts to the subframe beam and then bolts to a hard point I added to the sidecar frame. The motorcycle essentially rests on this crossmember. Now the crossmember is so dimensioned that the Tandem and the sidecar wheel are near dammit perfectly aligned with each other. I allowed for correction with shims if it ever became necessary at the side car hard point. i also reinforced the inner tube beam of the side car chassis with a 2"X2X3/16" angle. So I can create hard points later if I decide to move the car backwards to decrease the lead. I also use it to distribute the Vertical loading from the tow bar which is attached to a mount at the front where the crossmember and  and the re-enforced beam come together. The tow bar is just a bolt on. The bikes wheel ride about 5" off the road and because it rocks on the tanden should never ever contact the road unless everything else has gone to hell. Now I had to make a towing trim link to go on the side car so I can raise it up the level the combination out from side to side with a parking attachment point for my electric trim actuator when towing.  This has been a 1 step forward and hopefully only a 7/8 step back at each stage of the way. However I am now in the weld out stage and should have it completed during this coming week. I am also designing a much lighter rig for a very good friend who runs a Antique BMW 500 cc rig with a car. That one, tho much simpler also has its problems but I have learned so much from building my rig that its a piece of cake by comparison. I will probably go with a single Class D wheel on the bike side. I have set a goal of 30 mins to install or remove the towing rig but I believe I can do it in about 15 minutes and then put all the pieces in the car trunk Till its time to go home. I will leave the rig in the trunk of my Mercedes 230 which is our travel car. I do not expect to be rescued but if it happens my wife can just drive the Benz To me and not have to screw with a trailer etc etc. With a 1000lb load the Benz should be happy  

                                                                                           Later Chuck

Well I tested the rig with my wife driving the Benz and me following in my truck. I started out with about a 5" deep pothole and she eased the car thru the hole and the tandem which follows the same track as the left wheels of the car went thru the pothole. I planned that the bike back wheel would be out of gear so that the wheel would act like a 3 rd wheel. well it kissed the road when the back tandem wheel was at the deepest point with the rear suspension only moving very slightly just like I  had planned I am not worried about the front wheel as the towbar is only 50" long and there is no way you can get that wheel on the ground. We went for a little drive and the rig just followed the car. Becky says that the only time she felt the rig was braking she could feel the extra weight. Everything tucks right up in the trunk. So I call this venture a 100% success. This is made for hiway towing on reasonable roads tho it will traverse some pretty bad road if you go slow. That walking beam makes the bike just float along when traversing a heavily trucked hiway. I thought of slaving the bikes lights to the tow car but believe that I will just make a towing light board that can go on the back as part of the tow rig.

Now I have the best of both worlds I can take my bike along when Mama travels with me and not have to worry about getting my trailer ripped off at the other end.  A very real concern. I also do not need another special trailer

                                                                         Later Chuck

CCjon has reacted to this post.

Chuck, your description sounds like it worked perfect. Any photos available?


It really beat my best hopes. Like I said I am a digital dumbass and when one of my grand kids visits I will have them publish a lot of photos. The best part is that to solve the design problems I had to work on associated problems like jacking for example. That is a classic problem and the way I solved that was to create  a jacking point on the car and the front of the Mcycle under the left side floor board then also a add on that goes to the swingarm to lift the rear wheel. I then use a Mercedes side jack that fits the points to jack whatever wheel I need up. I tie the front brake with a cord and put the rear wheel in gear and engage the reverse drive so nothing can move when I am jacking. If I need to go very high like when putting wheels on the tandem or taking them off I just put a piece of 2X4 under the jack to get the extra height. My bike is now very custom built and I only have to replace the belt final with a chain and also the alternator/charging system, also to replace the Ural wheel with a HD black spoke mag/disc brake/car tire, to pretty much have the bike completely done except for final paint after it proves itself this summer. If I still find the steering objectionable at that time I will take the lead down to 10% with the option of going back to 15% Its 18% right now

To look at the bike it just looks like a slightly different Fat Boy but if you know what you are looking at you will see that this is very definitely a Horse of a different color with a lot of radical points to it. This thing is built to go to the moon, if there was a road there, and come back under its own power. Its a Road Warrior, it functions like one and rides like a comfortable armchair whilst being as bullet proof as a HD Evo can be made

later Chuck