Strange request, but what better place to ask?

[SKR8PN]

I know the braintrust here is into just about anything with an engine on it,so here goes..........
I bought Willy an mini bike to use as a pit bike. I love this girl to death,but,coordinated she is not   She promptly crashed it on her second ride.    I am thinking seriously about making a sidecar for this thing      Anyone here now any RULES about building a sidehack? You know,like axle placement,seat height,yadda,yadda yadda??
I have done a couple of searches and come up empty handed. Any help or thoughts along the lines of design would be greatly appreciated. Remember, this is only a 4.5 hp unit,so lightness is important

[enjenjo]

I've built a side car or two    

For what you want, you need three mounts. One low at the rear near the rear wheel, or front of the swing arm if it has suspension, one high at the rear on the seat post, or top strut near the seat post, and the third near the neck, about even with the neck bottom. This will triangulate it both ways, making it plenty strong. The centerline of the sidecar wheel should be 4" to 6" in front of the rear wheel centerline, to make it more stable, so it's not easy to tip over like a tricycle. More than that, and it gets hard to steer. You want the height of the sidecar wheel set so the minibike is not quite vertical with the rig setting on a flat surface, 1/4" difference is plenty. This is done for the right feel riding it. For some reason if you make it the same, the bike feels like it's falling away from the sidecar all the time. The sidecar wheel has to have some camber compared to the minibike, you want it to lean in at the top a bit, otherwise it's hard to ride in a straight line. If you have suspension on the minibke, you can use a swingarm for the sidecar wheel, so it doesn't throw the bike all over the place, if no suspension, you can mount it rigid.

Riding one is a whole new experience, it rides like a car, you have to steer it, unlike a normal bike where you do a lot of leaning. It takes some getting used to.

[purplepickup]

Jim, there's a sidecar forum here: http://www.sidecar.com/megabbs/category-view.asp .  I poked around in the technical discussion section and found some threads that might answer a few questions.  There was reference to a "Rig setup" thread but I didn't see it.

Enjenjo is right, riding a bike with a sidecar takes some getting used to.  Maybe a motorized trike would work for Willy.

[GPster]

There is a magazine for sidecar enthusiasts call Hacked (or maybe only Hack) that is from up around Clarksburg W Va. They used to do some business on line so you might find them that way. Linda and I were subscribers when we were doing that  and maybe for your purposes it will help Side caring isn't like motorcycling (you don't lean into curves) but it does add balance with the cost of being harder to steer. They had a guest technical editor that was a retired engineer/teacher and I had collected his articles but I gave them away when I sold my last bike. Here's some of what I remember. The wheelbase of the two-wheeler is measured from the front axel center to the real axel center. This is the proper way to measure it because that will give you the center of the tire contact area. Because the center of the arc of a turn is outside of the line of the wheelbase the sidecar wheel is always swinging a different arc than the line of the cycle tires. To keep from scrubbing the sidecar tire so bad the rule of thumb is that the sidecar axel is ahead of the rear wheel axel 10% - 15% of the cycle's wheelbase. There is only a thought on the width that the sidecar wheel is mounted from the rear wheel. The wider the better and I've never seen one that has a tread width more than the wheelbase. There is no imaginary place to aim the sidecar wheel. A straight line from the front line of the bike wheel is what you use and thesidecar wheel is parralell to that line with 1/8" toe-in. Ordinarily you figure on lean of the wheels loaded but that has to do with suspended vehicles so I wouldn't think it applies to minibikes. One other idea though. The center of gravity of the vehicles is not on the ground. It is easiest to imagine it at the top of the seat  with and operator sitting on it (maybe higher up with some women operators) so any weight placed low and out near the sidecar wheel will lessen the tipping problem. Because you said this would be a pit bike a tool box and/or a spare battery for jump starts would be helpful. If you have any definite questions, ask them and I'll try to help figure them out. GPster

[SKR8PN]

Jim, there's a sidecar forum here: http://www.sidecar.com/megabbs/category-view.asp .  I poked around in the technical discussion section and found some threads that might answer a few questions.  There was reference to a "Rig setup" thread but I didn't see it.

Enjenjo is right, riding a bike with a sidecar takes some getting used to.  Maybe a motorized trike would work for Willy.

George,your just not right  But I'll tell ya what......that picture put a whole 'nuther idea out on the floor  I shall return later,i gotta go take care of some business

[58 Yeoman]

Be easier to put on training wheels.

[kb426]

How old is Willie? Maybe you're pushing things a little to soon. Most every child crashes. That's why we buy helmets and other protective gear.

[34ford]

Willy is his wife if I remember right   not a child, so I don't think you want to ask an age here      

[SKR8PN]

Lets just say Willy is " old enough to know better,but to young to resist"

I kinda LIKE Georges idea of a trike setup........might be easier to build AND easier for her to ride.  Me thinks I should look into this one a bit more.........  

[Crosley.In.AZ]

A side car takes so getting used to .

Even at slower speeds.  I'd look into a trike type set up on 3 wheels , rather than a side car / hack

[kb426]

Boy, did I step in that one.

[Crosley.In.AZ]

Boy, did I step in that one.

yes ,  you wear it well though!


 :!:

[Leon]

I've owned a sidecar and it can be worse to ride than a bike without one.  In a right hand turn, you can pick the sidecar up and the bike leans left, causing a rapid left turn.  I taught motorcycle safety for the Navy for 10 years and had a couple go through my class.  They had the same problem under certain conditions.   I'd suggest converting it to a trike.

[EMSjunkie]

I taught motorcycle safety for the Navy for 10 years and had a couple go through my class.   .

Wet Bikes  :?:    :?:


Vance

[manyolkars]

I have two  sidecars. One on a 1942 Harley and one on a Cushman Eagle  motorscooter because I have two sons and no wife.  
A sidecar is VERY difficult to master because you have to go against the grain of common sense to operate one.
    When turning right and the sidecar comes off the ground, the first thought is to turn left to set it down.  But you have just steered into oncoming traffic!   The first time it happened to me, I was very forunate that oncoming traffic stopped for me.  There was also the time I ran over some bushes in somebodies front yard while learning.
        The solution is to lift the car HIGHER!  It is counter intuitive but it puts you back in control.
  It takes a LOT more effort to turn corners because you steer instead of leaning.