rotax in f125

Daniel Morency · Posted: Sat Apr 08, 2006 5:10 am Post subject: Kart Classes in Solo2

I'm the kart Chair in our local (Non-SCCA affiliated) autocross club. We have several other kart classes for adults, running on the premis that we can get adults and their children to share karts and race together (but not vs. each other)

Check out our website for the rules that we currently use. We have corresponsing rules compared to the SCCA junior classes (except FJ1, a restricted briggs) and a FSS class where we allow anything without a gearbox that we deem to be safe.

Check it out at www.cumberlandmotorclub.com

Please be aware that we work very hard to make our running very transparent to the cars, they don't like losing to the karts at many venues. Smile

Last year at one event a 9 year old got FTD, the course was so short and tight!

This year my son is running a KT100 with a 4 hole can and it looks like I'll be running a KT100 with a pipe in our FSS class. I may try both to see how much more comes with the pipe vs the can.

It helps to make autocross a more family oriented event. We spend a bunch of time in Kart schools to get the kids up to speed and prefer if the also race at the local rental indoor track for experience.

All SCCA regions can create and operate region specific classes, just get involved and work to make it happen.

Dan

Vernon Head · Posted: Mon May 01, 2006 4:57 pm Post subject:

Jason, do you weigh at least 385? That's the minimum weight in the class, regardless of engine. Rotax weight minimum was 355 last time I looked. If Sebastian could weigh 355, he might have beaten you by another half second.

Brian Garfield · Posted: Mon May 01, 2006 5:46 pm Post subject:

Not so Vernon, according to the rules I read. A Rotax, being an alternative 125cc 2 stroke motor without front brakes, runs at a weight of 360lbs. It must run at 385 if you add front brakes.
19.1.C.2
"Other Allowed Karts: ...All karts with engine configurations other than moto/ICC 125cc, that are allowed to compete in F125, must have at a minimum, a single rear disc that brakes both rear wheels equally and adequately for the power plant used. The addition of front brakes is optional; however, the kart must then be run at the 385lb minimum weight."
19.1.D.3
"Other Engines: Engines must be either a) mass produced single cylinder two-stroke engines not to exceed 125cc or...
...Karts with engines under this specification must run at a minimum weight of 360lbs."

Did I miss something?

I'm sure there are plenty of other variables based on how each driver was doing, what tires, etc., etc. But to me, with Jason's recent experience, it does sound like you simply loose at the start. At a Pro Solo, that's a very big deal, especially with the shorter courses. However, throw in a 90 degree turn at the start and a 60+ second Tour course, you even things out quite a bit.

It's not the first time I've heard this though. What I understand is that it is common for the shifter driver to not "carry" speed as well because they don't have to, and this sometimes actually makes the shifter driver slower even at the higher levels of experience. So, the shifter driver tends to overbrake for turns where the clutch kart is always carrying the maximum speed possible. I'm not saying this is always true, only that I've heard it several times, even from drivers who own and run both.

Brian

Wes Greene · Posted: Mon May 01, 2006 6:17 pm Post subject:

I ran the rotax weekend before last. I was at least four secs off the fastest shifter. That was with the wrong jet and a sticking powervalve. The start was real slow. I don't believe any of the shifters had real clean runs either. All and all I would say equal drivers with everything right....the rotax should be a couple of seconds slower. But no less fun!

Vernon Head · Posted: Mon May 01, 2006 8:40 pm Post subject:

Sorry, Jason. Brian is right, I need to read the rulebook more often. However, I couldn't find any restrictions listed for the TAG motors as far as clutch, porting, etc. I could be wrong about this. But if not, then you could probably get well over 30 hp and run a mult-spring, multi-disc clutch to help you get off the line quicker. Then, with no shifting and lighter weight, who knows?

Daniel Morency · Posted: Wed May 17, 2006 6:23 am Post subject: Rotax DD2 in F125

Can a Rotax DD2 with it's two speed gearbox, run in F125?

Thanks

Dan

Vernon Head · Posted: Wed May 17, 2006 9:41 pm Post subject:

No gearboxes allowed, except moto and ICC.