Calkins
We ran a single cylinder MX bike last year at BUB....here is some of what we learned.
Most offroad trans are designed for trail or track riding and seemed to be geared awefully low for land speed racing. I know you can change the final ratio, but not always enough to deal with the different trans ratios and patterns. By the way, do a quick check and make sure the front sprocket you want to run 'fits' the cases and don't forget that rear drum hub limits how small of a rear sprocket you can use.
According to
Jack D and my limited experience, the power delivery of a single or vee twin seems to suit the salt surface better than some of the in-line four cylinder high RPM motors.
An big offroad, top heavy, MX gas tank is the 'worst' thing imaginable to try and tuck behind!
Considering the chain...we stretched the swingarm and had no problem running a super long chain, but we also had the swing arm at a realistic angle.
Rick G, one of our teammates, made a billet triple tree that returned all the trail lost from lowering the forks.
Considering steering/suspension angles, read some of the 'math' books and web pages...it becomes obvious what ideas work by their popularity. I picked a bike that had demonstrated stability at
our target speed and copied those angles.....with runs up to 132mph the bike felt like it was running on rails the whole week.
Make sure the steering damper is designed for road race or flat track. MX dampers typically only damp one direction and allows the bars to easily return to nuetral....road race damp both directions.
The tire manufacture would NOT offer ANY opinion about a DT tire on the salt, but after talking with a few local guys that compete at Springfield I feel good about about and can argue that the tires are run in the tall 130s in the mile.
and the good news.....
The MX bikes are great for making friends...most everyone has a story about their first dirt bike.
Old MX bikes are $$ cheap, especially when you and your buddies have bits and pieces shoved in the back of garages!
Even better, they are simple.....there was so much other stuff going on at the event that it was a wonderful to be racing a KISS bike.
Any single cylinder bikes is ~25% the width of every hyabusa that has rolled out of the factory.
and the best info/advice I think anyone can offer.....
Do your homework, ride what you have to start if the tires meet the required speed rating, then you will know what you need to do.
Good Luck!
Mark
