April 9, 2016 at 6:35 am #64141
IAME X30 Super shifter, for those not familiar it is a 175CC shifter motor, makes 49hp at 13,000 RPM and 20 lb-ft of torque at 14,500 rpm. Anyone have thoughts on a weight for this motor?, seems like a possible option for us heavier guys, but only if it wouldn’t upset the apple cart, wouldn’t want a $6000.00 motor to be the motor to have. Thoughts?.
April 9, 2016 at 7:46 am #64145
Per current SCCA rules it is not legal due to the wording for no engine bigger than 125cc.
I have made the claim that a mod moto that has been overbored is illegal for being higher than 125cc. But never filed any paper work, since it is most likely my driving that lost not an extra 0.2CCs
As nice as it would be for the larger guys to use a bigger motor to be more competitive. I am still going to say, KM and karting in general is a physical sport and benefits from drivers in good fitness.
Sure 410lb with a KZ engine can be tough to make if the driver is taller, but most race series run around or below that min weight for KZ engines. With a good driver, chassis setup, and good engine, I don’t see why they would not be able to place in the trophies at nationals.
April 9, 2016 at 8:28 am #64146
Good fitness only goes so far, a person cannot lose 3 inches of height no matter what they do, honestly this doesn’t matter to me, I can run at 410 and if I wanted to be more competitive I would buy a KZ, not spend $6000.00 on the X30, and yes people can place at nationals overweight, so it is by no means worth upsetting the apple kart (ha, see what I did there), I just think it is worth discussion for the future if KM continues to lose entries, something to potentially attract those who wouldn’t normally think of a kart because of weight.
April 9, 2016 at 8:36 am #64148
Daniel is correct. The limit in CC for a gearbox motor is 125.
If I recall correctly, an allowance is made for a larger single-speed clutch-type. More than a decade ago I ran a Biland SA250 (4-stroke twin) on a test basis at a Pro Solo. Way too slow off of the line to be competitive there, perhaps better at a regular autocross?
As far as the overbore goes, for Moto engines at least, it is not possible to do like a car engine, as they have the Nickasil coating in the cylinder. So, +0.020″ (or 30, 0r 40) is not something which can be done without a subsequent replating. The answer there is to recoat at the stock bore, if some repair is needed. Sleeving (typically with iron, possibly an alloy steel) is also prohibited.
There are “Big Bore” kits which increase the CC’s significantly. Those of course are illegal.
April 11, 2016 at 6:27 am #64222
I think the CRF250 would be a better engine for heavier drivers due to the increase of torque the 4 Stoke makes. I think a 415lb min weight would be a good balance. The increased torque and large powerband would make it very good for autocross.
April 11, 2016 at 8:01 am #64235
The 4-stroke gearbox 250 has been talked about for many years.
But no one took up the fight to get it approved. There is at least one company which has a conversion kit to set one up for a kart, likely that would be not too hard to find. Consult with the current Kart Committee members to see what it would take. I personally have thought it a good idea for a very long time.
The single drawback always mentioned is the expense of repairs should anything go wrong with the engine. Top ends of those motors are not easy like the 2-strokes.
April 14, 2016 at 8:00 am #64407
April 14, 2016 at 9:28 am #64419
I don’t personally intend to write a letter about this right now, it is not really an option I need for myself, it is tricky for me to get to 410lbs but not impossible and it is on me to do what needs to be done. I just wanted to discuss this for the future, KM still has good numbers at Nationals at the moment, not what they used to be but still safe, I think it is still wise to consider options for the future that would open the class up to larger guys, if we continue to see a decline, KM is a class that people tend to have strong feelings about, and if the numbers are not there it would be more vulnerable then any other class.
April 14, 2016 at 12:23 pm #64426
Scott, letter summited.
As far as attendance for KM goes, it could defiantly improve on the local level, as well as national.
There is a big hurdle for new drivers entering KM between finding a mod moto engine, or dealing with the extra engine costs of a KZ, and 2 strokes in general. It is not that appealing for new drivers, it is not a class you can just jump in and be fast. That is why street class has taken off, bolt some RE71s on and race the whole season, cheap, fun and competitive.
KM needs to look at alternatives, such as spec Honda as the base engine config of the class, not hidden in mod moto rules. You see listing here everyday for spec Honda engines, how often is a mod for sale?
I have asked a few people why they don’t want to drive KM, most say they don’t want to deal with 2 strokes and the maintenance that is also required. 4 strokes they would like. Currently the CRF250 is an expensive option, and also illegal for the class. If a national karting series starting running them I am sure the prices would drop.
Then there is the L0206/clone, very popular class at kart tracks around the country, while not as fast as a single speed tag. They are cheap, reliable and easy on tires, meaning easier entry to the class. This would be a far stretch to run in the same class as a shifter and be remotely close in times. I hate the ideas of additional classes, but may be we should explore and look deeper this route. Again currently legal but not competitive against a single speed TAG. One thought is to remove the age cap on FJA and make it junior, senior and master in a single class structure?
For the existence of KM to continue I think we should start talking about what needs to be done to get newer drivers into the class.
April 14, 2016 at 4:44 pm #64433
That is very true that the top reasons for not driving a Kart have nothing to do with competitiveness and more with maintenance, work, and steep learning curve. I’m biased as I love driving karts and never really get it when someone immediately rights off the idea of a kart, but different strokes and such. But there do seem to be many avenues to grow this class and all are worthy of discussion, whether it be opening it to more popular local sprint racing class (shifters are not very popular in my area) or adding 4 stroke options for those who don’t like 2 strokes. I’m going to try and do my part next year when I get a different motor and throw my current motor in my old chassis and see if anyone wants to rent it, the first hit is free.
April 14, 2016 at 4:49 pm #64434
“the first hit is free.”
I think it was Jason Vehige who used to call his kart “The Crack Pipe”
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