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BRE LLC LOGO    Stock Appearing Kid Kart Engine Rule Set




A Simpler Rule Set for Kid Kart Engines that provides MORE EVEN competition than other rule sets.

Above all else, kart racing is supposed to be fun.  One of the most distasteful parts of kart racing for me is the unnecessary drama that too often occurs regarding kart racing rules, especially engine rules.  Many people believe that the best way to level the kart racing playing field is to make rules that require engines to strictly adhere to factory specifications.  They also justify that by saying that using “stock” engines will control the cost to the racer.  I do not agree with that notion.

The problem with strict stock engines is that in order to ensure that the engines all do conform, a thorough engine tech is necessary at every event.  Human nature is an issue here, especially in motor racing.  I simply know of too many people who use modified engines who claim that they were simply blueprinted.  If the requirement is that the engines are supposed to meet some strict tech, and there is not a regular, in-depth inspection, then cheating will occur, or at the very least, the perception will be that it is.

Stock is not cheaper either.  When parts cannot legally be altered to perform as desired, racers are notorious for searching out those special parts that come from the factory just a little bit different or better.  Or, racers will go to extreme lengths to disguise work that has been done.  None of that is cheap and racers pay a lot for “special” engines that have a winning record.

The Kid Kart class is not only a place for new drivers to learn the sport; it is more often than not the place where dads and moms too learn the mechanics of racing engines.  Very often in their tuning efforts they do things to the engines to simply tune them that are violations of the rule book even though that is not the intention. With a stock appearing rule set, new engine tuners are free to try different combinations and ways of "massaging" parts and observe the effects without the worry of being accused of cheating. Part of the attraction of racing is that it is an outlet for tinkeres to tinker. I say let them.

All of that is insistance on adherance to nit picky rules is way too complicated and is open to unnecessary politics and just is not fun.  All over the country there are tracks that have it right.   They simply say that in the kid kart class, the engine just has to be a C-50 or 51 and on the outside look like it does when it comes out of the box.  Do what you want on the inside. I love that.

Now there are those who will say, “That means I have to get my engine reworked to be competitive.”  That may be true, but it is very naive to say that is not also the case when the rules require “stock”.  In the vast majority of cases, the winning engines, regardless of the rules, have been thoroughly worked over, and often at great expense.  It is much cheaper to get an outlaw engine built once and for all and learn to tune it them to begin the search for that “special” winning stock engine. 

When the rules are stock appearing, there is no more room for accusations of cheating, or involved technical inspection.  You just run what you brung, and if you don’t have enough stuff this week, go find some more for next week.  It’s just simpler, easier, and lots more fun.

The following is a suggested rule set that I wrote and was adopted by the Unlimited All-Stars for their developmental class for 5 to 8 year olds. It addition to here, it can be found at:

UAS Kid Kart

Warning:   UAS Kid Kart Racing is extremely dangerous. All Parents and/or legal guardians of UAS Kid Kart drivers and their minor age drivers must realize and accept that racing accidents can result in severe injury or death. Participants do so completely at their own risk and of their own free will and it is ultimately their responsibility to not enter or withdraw from an event if they do not believe they are safe.
1. Unless stated otherwise in what follows, all other previously stated specifications, rules and policies in the UAS will also apply to the UAS Kid Kart.
2. For the 2017 and 2018 season, UAS Kid Kart engine, safety and body specifications will be monitored and adjusted as needed to maximize safety and maintain a balance in competition.    This policy exists because of how new this class is and will make development easier. After that time the same policies regarding UAS rule changes will go into effect.

Driver Eligibility
1.            UAS kid kart drivers must have a Minor Release, signed by both parents, on file.
2.            The UAS Kid Kart class is for drivers 5 to 8 years old.

Eligible Engines
 1.           Comer C-50 (cast aluminum blower housing) and Comer C-51 (plastic blower housing) 
2.            Other engines will be examined for inclusion in UAS Kid Kart as they are presented to the UAS national office for testing. 
3.            Engines are to be run in stock appearing condition.
A. This means that externally the engine must look as it does when it comes from the factory with the exception of the air filter and exhaust. 
B. The muffler hole sizes are non-tech.  (We have learned that bigger or more muffler holes do not increase performance but they do make more noise) Aftermarket tuned exhaust pipes are permitted but with a higher minimum kart and driver weight.
C. The air filter is non-tech, meaning that the competitor may use any air filter that fits provided that the filter does not incorporate some sort of external scoop or ram effect that is visible when the filter is installed.
D. Any drive sprocket ratio may be used.  Clutch and axle sprockets are non-tech items.
E. The fuel line from the tank to the carburetor is non-tech and an external fuel filter is permissible.
F. Internally the engine may be altered as the competitor sees fit with the exception of the stroke.

Use of Restrictors
On tracks designated as 1/5 mile or longer, engines must use a restrictor to limit top speed.  No restrictor is required on tracks less than 1/5 mile.
1.            Comer C-50 or 51 engines, restrictor maximum inside diameter is .276* (7.01 mm)
2.            Other engines (to be determined as other engines are **submitted for testing)
Engine Stroke Tech

The stroke of Comer C-50 / 51 engines is not to exceed 1.505* and it is to be measured with a dial indicator and a suitable adaptor that attaches to the spark plug hole. (This is very easy to do without disassembling the engine but eliminates very expensive stroker crankshafts*we don*t worry about the bore size in that no suitable over size pistons are available anywhere and it is very impractical to resize a cylinder with an integral head)
Specifications for other engines will be included after they are submitted for testing and approval

Minimum Weight
1.            Comer C-50 or C-51 with factory equipped muffler..150 lbs
2.            Comer C-50-C-51 with aftermarket muffler or tuned exhaust..160 lbs
3.            Other engines. To be determined as they are submitted for testing.

Tires and Wheels
1.            The largest permissible diameter tire size as marked on the tire is 11. 
2.            5 or 6-inch diameter rims are permissible. Maximum rim width is 6"

Gear Ratios
1.            The axle sprocket is a non-tech item.  Use any rear axle sprocket that you want.
2.           You may use different clutch sprockets too.  The ones used on the Comer 80cc engine are permissible.  They require a different clutch nut.

Chassis are subject to the same safety specifications as the UAS.  Although this class is intended for the same kid kart chassis that are legal all over the world, as a local option, race directors may allow full size chassis to be used provided the body work on the kart falls under the same minimum measurements as other kid karts and must be altered to allow the young driver to be easily work the controls and be properly supported.

Body Work
Maximum height from the ground measured at the front axle center is 13, maximum height from the ground measured at the rear axle center is 20
Body work approved by CIK, IKF or WKA is permissible
Otherwise all rules pertaining to UAS body work listed in Section IV, B. 4Body Work will apply

Rear Bumper
The rear bumper must extend at least half way across the tread of the rear tires.  This can be done with a full coverage bumper or a device such as a "hopper stopper".

Driver Safety Equipment
1.           UAS Kid kart drivers must wear an approved chest protection device.
2.           UAS Kid karts are to be equipped with a tether type engine kill switch that will shut off the engine if the driver is separated from the kart.
 3.          Other driver safety gear is to meet the same specifications as the UAS.
UAS Kid Kart Committee