I used to be pretty friendly with a guy who built a few super karts of his own. He made a revolving jig so welding the frame would be easier. The jig had movable fixtures to allow the tubes to be located in different positions so he could make any design he wanted on the same jig. With a 600cc superbike engine you'll be the fastest thing on the track, is there such a class for racing this or is it just for fun?
Just some of comments on the design, you might want to consider running without the cross brace under the seat as you will need to get the bottom of the seat about 1" off the ground otherwise it may get too top heavy. Another thing is you might want to consider running a pair of inboard chassis rails from the inboard axle bearings which run parallel with the outboard rails and then merge into the outboard rails approaching the waist line of the frame, or use one u shaped rail which runs from the inboard axle bearings and across the front of the seat, this could have bolt together, rubber insulated stays which join the inner and outer frame near the waist line which would be adjustable to control torsional stiffness of the frame. Also, most modern karts have frames that start to taper in to the waist line much further rearward than your design. You may also want to run a torsion blade across the rear of the frame, turn the blade virticle for max rigidity or flat or removed for max flex.
A roll cage would add to much weight. When you go and buy a $200,000 lambo you pay a little for going fast and a lot for safety. They have high safety coefficient. Since i do not have the money i am throwing safety concerns out the door. The lower the safety coefficient the cheaper the project. No I am concerned with safety but i want a crazy power to weight ratio.
have you measured up the engine to see how much space is required to make it all work? 250cc karts frequently run the driver offset to one side and the motor on the other side as there isn't enough space to mount the motor behind the driver. Mounting the motor behind the driver makes the frame excessively long which makes the handling less responsive. See the pink Thundermaker frame for an example of an offset frame.
If you think you can go with a conventional frame, take a few design ideas from the blue frame, it's a very conventional, common design and well proven to work on the track. These days the design differences between the different frames is so subtle that you should be able to copy pretty much any modern frame and end up with a pretty good kart.
I enjoy visiting nearby Watkins Glenn raceway to watch the Kart races. If memory serves me correctly, they ran a 500cc shifter-kart class that might give you some ideas for your design. Also, there is a “super–kart” class very popular in Europe as wells as in the US.
If you’re designing a one-off kart (not intended to meet certain class specifications) but instead as a fun personal project. There are many individuals & companies building mini-sand rails that run engines up to and including the Suzuki Hayabusa 1300cc engine (even with turbo’s)! There is even a company now which produces a mini version of VW’s type 1 transaxle for just such an application.
Trouble is thats way beyond "gokart" classification. There you're into SCCA formula size stuff. It's still fun though. Do me one favor though, WEAR LEATHERS.
CNCPro, I live near ROAD AMERICA, they added a kart track in addition to the 4 1/2 mile road course. Lotsa good stuff.
Last edited by RICHARD ZASTROW; 04-13-2007 at 12:57 PM.