USCA Sidecar Forum

For some extra information about navigating the forum you can go to Forum Tips

Please or Register to create posts and topics.

Well I crashed

Wow that bike is gorgeous, that is going to be a beautiful set up once it's done. can't wait to see it 

 I would check to see if the can program it for a trike mode after you install the sidecar as the bike won't be leaning any more. The RDRS works different on a trike compare to a solo bike. As far as the wreck goes, must being going to fast for the road conditions. Had someone that had the same problems, the bike back in would start going back and forth out of the blue. He decided before it went back to the dealer to get check out to go for one ride, the next day it was going to the dealer. Long story short he didn't have your luck and he don't have to worry about his bike any more. Good luck with your new bike. 

Smitty, thanks for elaborating.

 The bike had trike front end well test and done right. LEO cited road conditions. I had a friend right behind me on his sidecar rig. He said the back end jumped right then left and the bike was gone.  When back end jumped the front went into a stop to stop wobble in a second I was down.

Thinking about it, I do believe that the road-tire's flat surface is the cause, irrespective of it having been ridden before without serious issues. Why do I believe that?

I come from solo riding, for forty years or so. In addition to my Ural rig, I currently own and ride a Ducati Monster 1200S, which is a seriously fast and powerful bike. Remember, I live in Switzerland and can ride Germany's autobahns, right across the border. And by "fast" I mean: up to 150 mph. Bikes of this speed and hp-class react very sensitively to changes of tire brand, thread depth, air pressure and you name it. It's a very delicate thing. So, if you survive for long enough, out of necessity you develop a sensitivity for tire-related issues.

That said: on a solo machine, due to its stock(!) tire shape (cross section), there always is a point of contact with the road surface for each tire. Which results in a line of contact from the front wheel's point of contact to the rear wheel's point of contact. As long as this line of contact supports the combined center of gravity of machine plus rider, the ride is going to be stable.

If you have a car tire on the rear wheel, with a flat surface, said point of contact morphs into a line of contact, transverse to the direction of travel. The direction of the supporting line of contact from front to rear wheel becomes undefined, at least becomes less precise. I would expect a seriously "soft" feeling from the rear end, which indicates a lack of lateral guidance. This may still work well enough, as long as road conditions are perfect.

If, however, by some random variation of the road condition like tar patches and/or grooves, the flat tire surface only has contact on - say - its right edge, the previously undefined direction of the line of contact suddenly does become defined, in an unexpected way. As a rider, you find yourself sitting to the left of the now defined line of contact, unsupported if you will. The bike reacts by leaning left, with the handlebar swinging left.

But, since patches of tar are typically short in nature, the left-leaning influence soon disappears, maybe even reverses into a right-leaning influence (if a left patch of tar follows).

And it reminds me of typical situations in riding a snowboard down a slope with only a shallow gradient, where you try to avoid doing turns, because those would involve lateral slip, which means: energy loss, and the possible risk of a long walk with your snowboard unstrapped. So, as you're sliding along, trying to avoid any lateral grip, suddenly one edge of the board does grip. And it feels like the rug being pulled laterally from underneath, and typically results in a crash as well.

Anyhow, my take on this is:

Never, ever, ride a tug machine with one or more car tires mounted as a solo machine. Having done so before without a crash is no proof of this being safe.

If my verbal explanation is incomprehensible, I'll gladly supply  a sketch or two to support my thesis. Just ask.

P.S.:

on a very related note: if the handlebar could swing between right and left stops, the steering damper was either inoperational or too weak. Because its very purpose is to prevent just that.

 

 

1bmwmc has reacted to this post.
1bmwmc

    I take no issue with your points.  Over the years I have ridden a lot of customize bikes . Some great some bad. Just because some thing never caused an issue in the past does not mean it won't happen .  Seem county got out there did some more road patching real quick.

 

 Shame on the county. good to see the taxpayers money at work. Did the person behind you have any problems.  

 No he was on his sidecar rig and riding toward the inside of the lane. He stores his sidecar rig at my house for the winter. Came over that day and it was so nice out rolled it out to ride a bit. Like many once bitten by the love for riding he has 3 bikes and no where to store them. I have plenty of room.

       We are closing the book on the crashed bike. We will miss that Gold one but it is over. Now we need to focus on the new one and getting the sidecar painted and on. That should all be done by late Spring .  The new bike is home .

20201203_135203

Reardan Tom has reacted to this post.
Reardan Tom

  Are you going to install a Trike front end on it?

 I am not sure . it work good but then again I have not compared it to one without. I have talked with a couple that have bikes like mine and did not do it and claim it works fine. I can always just have Hannigan put one of their raked trees on.

The different tries/wheels on the bike seem to make it feel a bit more nibble if that makes sense.

  The new tug is sitting in bike room. Only managed to get 490 miles on it before first real snow.  Working on getting things I want done to it. The red lights in the back had to go so replacing every thing with Smoked LED's.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Uploaded files:
  • 20201224_133811-Copy.jpg
  • 20201230_165809.jpg