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Discussion Starter · #23 ·
I'd look for a decent scooter wheel that you can use and make work, then pick a scooter tire for that wheel. Most scooter tires are rated for well over 450 pounds load.
I’ve got a good friend with a beautiful Vespa, I’m gonna consult with him about it …. Later Mate…..Blitz
 

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Discussion Starter · #27 ·
OK @GapRunr …. After playing around with some scale work-up’s I’ve decided you have a valid point about the leverage variable. It’s unexceptable. It’s advantage would be rare but it could indeed happen … sooooo
I’m modifying the tow rig portion on the motorcycle to be fixed and rigid to the moto frame and the hitch and swivel point to be at the very rear only and be a universal home built to give full range of motion. Thanks for your expert advice … I will benefit from your experience and I thank you for you time and advice. Look for an update soon and a new version ..(white PVC mock up).. of the structure on the bike itself ……,,,,, BeWell StayUpOn2 ……… Blitz
 
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I’m modifying the tow rig portion on the motorcycle to be fixed and rigid to the moto frame and the hitch and swivel point to be at the very rear only
The ever-dreaded can of worms... When you accomplish A, then it impacts B which must then be addressed. Building a swivel and U-joint at the rear of the bike completely eliminates the unlikely but possible side torque on the bike. But, now, all the trailer weight is behind the bike. The rear shock preload will have to be adjusted or the shock replaced to compensate for the weight. This would be a great time to consider a progressive (dual rate spring) rear shock but one must consider the fulcrum affect which will reduce weight on the front wheel as a direct correlation to tongue weight. Stiffening the rear shock will cause less weight transfer to the front wheel.

I have a travel trailer with heavy tongue weight. Even with load levelers my front wheels wear unevenly as a result of a fulcrum affect of the weight on the hitch loading the rear axle and reducing weight from the front. Adding spring strength to the rear axle directly reduces weight even further on the front axle so with this trailer fully loaded, the front axles weight is less than when the truck isn't loaded.

Many years ago, I commissioned a trailer for my motorcycle that was small enough to be towed behind my bike yet strong enough to carry a motorcycle. It was indeed small enough, and strong enough but way too heavy. My front wheel would leave the ground on acceleration and I was never able to tow it with a motorcycle. I still use it to carry stuff but behind a vehicle. Tongue weight on Blitz's Shadow won't transfer to the frame anymore and must be carefully considered when loading your trailer to keep enough weight on your front tire. Your initial hitch design shared the load between the front and rear wheels.

Additionally, the height of the hitch is a critical dimension now as well. If your hitch is above wheel axle height, you'll be more likely to wheelie during acceleration. If the hitch is below the axles, your front wheel will get lighter during braking. That is regardless of tongue weight. So, elevation is a consideration. IMHO, you'd want your hitch to be slightly above the axles so your front wheel will be loaded during braking. But not so much that your front gets overloaded in hard braking. Once again, your initial hitch isn't affected by this either.

So, basically, you'll be trading one potential handling hazard when in unusual angles to another potential hazard caused by cargo loading.
 

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Discussion Starter · #29 ·
The ever-dreaded can of worms... When you accomplish A, then it impacts B which must then be addressed. Building a swivel and U-joint at the rear of the bike completely eliminates the unlikely but possible side torque on the bike. But, now, all the trailer weight is behind the bike. The rear shock preload will have to be adjusted or the shock replaced to compensate for the weight. This would be a great time to consider a progressive (dual rate spring) rear shock but one must consider the fulcrum affect which will reduce weight on the front wheel as a direct correlation to tongue weight. Stiffening the rear shock will cause less weight transfer to the front wheel.

I have a travel trailer with heavy tongue weight. Even with load levelers my front wheels wear unevenly as a result of a fulcrum affect of the weight on the hitch loading the rear axle and reducing weight from the front. Adding spring strength to the rear axle directly reduces weight even further on the front axle so with this trailer fully loaded, the front axles weight is less than when the truck isn't loaded.

Many years ago, I commissioned a trailer for my motorcycle that was small enough to be towed behind my bike yet strong enough to carry a motorcycle. It was indeed small enough, and strong enough but way too heavy. My front wheel would leave the ground on acceleration and I was never able to tow it with a motorcycle. I still use it to carry stuff but behind a vehicle. Tongue weight on Blitz's Shadow won't transfer to the frame anymore and must be carefully considered when loading your trailer to keep enough weight on your front tire. Your initial hitch design shared the load between the front and rear wheels.

Additionally, the height of the hitch is a critical dimension now as well. If your hitch is above wheel axle height, you'll be more likely to wheelie during acceleration. If the hitch is below the axles, your front wheel will get lighter during braking. That is regardless of tongue weight. So, elevation is a consideration. IMHO, you'd want your hitch to be slightly above the axles so your front wheel will be loaded during braking. But not so much that your front gets overloaded in hard braking. Once again, your initial hitch isn't affected by this either.

So, basically, you'll be trading one potential handling hazard when in unusual angles to another potential hazard caused by cargo loading.
Thank you Gene, your insights are of great value to me. I’ve gotten similar feed back from my friends here …
The consensus here is to proceed with the original hitch design, conduct controlled tests and decide. We all feel as though the chances of finding my self at the kind of angles necessary to cause a problem are unlikely at best and the advantage of distributing the trailer tongue weight more evenly between the front and back tires is worth the very low risk of leveraging the bike with the trailer and loosing control. It would take a very steep and deep switch back turn to ever find myself in any trouble and because it’s a turn the odds of any significant speed are zero. Soooo … I’ll take my chances. I like those odds.
I have to get a new RoseBud tip for my OxyAcet torch today then out to the shop so I can mill the bearing mounts and decide if im going to re-enforce or re-make the seat support struts on the bike from heaver stock. To me the stock support does not feel substantial enough for dealing with the constant dynamic forces it will be receiving. Every time you make an adjustment at the handlebars in direction, it directly translates to forces applied to the trailer through the hitch connection as it tries to twist the steel… I want NO failures in metal fatigue or welds. When I get this under my thumb (in a couple days) I’ll get back here with updates and pictures. Again Gene, thank you for your time and brain power. BeWell Mate …………….. Blitz
 
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