Consistency between US circuits for weights/tyres

I have brought this up at some events before but figured it was worth bringing up on a larger platform.
I raced most of my life in the UK so the seemingly varied rules and regulations even regionally between tracks makes life difficult for drivers. For example in the UK, a weight and tyre are thr same for that class NATIONALLY. So you can enter a Formula TKM Senior race at any circuit in the country and the weight limit is 152kg, and tyres are Maxxis SLC.

Contrast that to the Midwest for example. I run 206 and 125 shifter and for my 4 local events (WRP, NCMP, SIRA AND BATB) require 3 different tyres and vastly different weight limits.
WRP use Bridgestone tyres, NCMP use MG, we had to use Hoosier in 125 shifter at BATB 2019. In both shifter and 206, weight limits can vary but 15lbs or so, which when you have to run loads of lead like I do, adding 15lbs isn’t easy. For example. 206 masters at WRP and NCMP used to be 370lbs, but for 2020 WRP increased theirs to 385lbs

I understand that in the case of tyres, clubs or tracks have agreements with tyre suppliers and in the case of weights, some people have desires to push weights higher. However, I really do think that there needs to be some consistency and cooperation between at least regional circuits. If I were to do a full season at 2 circuits and BATB, I’d need 3 different sets of tyres, which is a huge chunk of money.

Any chance this will ever change?

After 2021, we’ll be down to two manufacturers in the Midwest, I believe. I’m pretty sure WRP is gonna make the switch for 2022. 1 more year on the current contract. MG and Hoosier.

The weights are ridiculous high regardless and it 100% stems from the “make everyone happy and include everyone” mentality.

Senior is 375 and Master is 390 at SIRA.

I’ve made the argument time and time again and I’m met with a rash of responses of “I can’t get that low on weight.” Yet, at the track, I rarely see anyone without 20+ pounds of lead on the kart.

That’s not strictly true. It’s only true if racing within Motorsport UK competition. Though independent clubs largely fall in line with Mototsport UK regulations they are obviously not obliged to thus there’s the occasional deviation, as you see in America. Clay IKR for example use Maxxis Sport as oppose to the softer Mojo rubber. I think that’s because competitors have to run them for more than one race to save costs.

The UK has a lot of tracks in a small land mass and generally speaking it’s the same group of drivers and teams frequenting them, so homogonoisation tends to be a little stronger than in America. Obviously we have Motorsport UK as well. But even in historic TKM we have three series who run different tyres and different regs.

I can’t see the American model changing any time soon.

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That’s at your particular track though. For example, we have a TAG Heavy class in my area, that has decently sized people that don’t run a ton of weight, if any.

I mean, sure, the drivers could probably all get in better shape and lose some pounds, but when the average height/weight of drivers in the class is 5’8+ and 180+, it can get a little hard to match the weight of a 5’5" guy.

I’m 5’ 10", and getting weight down has been a little challenging, for what’s basically hobby racing.

There you go Alan ruining my logic :sweat_smile:. I admit I’ve been out of the UK scene for 5 yrs (my last MSA events were some TKM and 250 superkart events in 2012 and IKR events in 2014/5) but even then, there is still less variation than over here.

I agree I dont think it will change soon either sadly.

True, and 206 in general does seem to attract heaver drivers and thus add weight. NCMP are running a 206 light class with strong grids but there wouldn’t be enough at WRP for that.

I see you are in PNW. I loved in Yakima for a year and ran at Tri-cities a lot. I loved it and still miss that track.

You know me I sniff out stuff logical inconsistencies :slight_smile: I do understand it’s not as drastic as in America. I think it’s pertinent to remind people that if we compare Europe with America (connected landmass is compariable), in some ways its worse here. For example if I buy an X30 in France, and turn up to a Motorsport UK club for a hack my engine wouldn’t be legal.

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Much like IAME/Vortex/Rotax are currently fighting each other to establish their brand of TaG engine amongst the various kart clubs, tracks, series, and orgs. in the U.S., so are the kart tire brands battling each other for these same groups.

The competition is fierce enough that it ends up with the mess like it is now. And there is no overeaching sanctioning body making things more streamlined. In fact, to complicate things, some tracks and even sanctioning bodies are also the importers of specific tire brands here.

It’s a pain (although there is one small plus in preventing one brand having a monopoly), particularly when you want to travel to try different clubs or series, especially annoying when it comes to rain tyres, but I don’t think it will change anytime soon. If anything, the division and animosity between the different groups using different tire brands seems to be getting worse.

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It would be great if all clubs dropped the tire brand / specs entirely. I’m not sure how much money a club gets paid to do that, however. Maybe it’s substantial?

At our club track most people just run MG since that’s what the on track vendor sales. The regulations are void of any preference:

  1. TIRE SIZE: Must be CIK/FIA approved tires ONLY suitable for 5" or
    6" diameter rims.

  2. SPRINT TIRES: Only one set of new tires or two sets of used tires
    will be allowed per event. All competitors in Sprint, 2 and 4-cycle
    classes, must qualify and finish all heats on the same set(s) of tires.
    Tires will be marked after qualifying. It will be left to the Race Direc-
    tor or Chief of Tech to allow one-for-one replacement of a tire that is
    damaged by road hazard or accident. Tires may be reversed on rims,
    but must retain original markings.

  3. SPRINT RACING/RAIN TIRES: If the race is declared a rain race, the
    Race Directors may, at their discretion, waive the “qualify and run all
    heats” tire rule in Sprint events. The intent of this rule is to allow the
    competitor to choose the tire that he/she deems safest in these condi-
    tions, rain or slick. This decision may be made at any time during the
    course of an event and is to be used to assure safe completion of the
    event. Any such announcement of this change will be made to all com-
    petitors at the event at which time they may have the option to use any
    tires of their choice.

Generally the clubs get compensated to mandate a tire brand.

Are drivers willing to pay a higher entry fee to cover the difference?


That would not be great, because then racers would have to start carrying multiple sets of brands of tires depending on the conditions and track to get a competitive advantage. That would just make things more expensive over all.

At least with a control tire, you have a level playing field with what’s being run on. When people run open rain tires, you get these large gaps on performance, because driver X brought a Vega and driver Y brought a Bridgestone.

Although I wish we had a national spec tire to make it easier for racers to enter a different region and not have to buy tires, I totally understand why certain regions lock to a single tire supplier.

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I’d imagine if choice was an option, we’d all end up runjing the same tires for a given track anyways. Not sure that it would make sense but we’d end up with possibly different tires for each track. So, Yellows at etown but whites at NJMP or something. Ugh. Gonna need more hubs.

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You definitely would, but people would either.

  1. Run whatever tires they had, and then complain when they had the slower tire compared to the winner.

  2. Complain that they had to run too many different types of tires to be competitive.

A spec tire makes more sense because everyone has to just run the same thing, and setup around it.

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The only way you can get nationwide adherence to a particular spec is if the class owners introduced strong incentives for clubs to join their programs rather than run independently. Stuff like frequent racer miles and all that kinda thing. You’d need officially sanctioned clubs and that kinda thing. That requires hard miles and serious salesmanship. Is it worth it? I don’t know.

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That too. I’m not sure, other than someone who had an insane passionate for the sport, and could be a good salesman/organized, if it would actually be worth it to put in all of that effort.

The other thing is that the United States is BIG. Much bigger than mainland Europe, so the number of events that we cover across a few states, could be a few countries for our European colleagues.


The only way a tire war works for the manufacturers, the series, and the drivers is when there is a sanctioning body that is heavily invested in the tires performance and overall racing product. With all the different clubs/series this isn’t possible and you end up with what Davin said, drivers bringing multiple brands/compounds each week.

Also with the shorter distances of sprint races it’s hard to justify having a war over tire performance when even a soft compound tire holds up well over an entire race.

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Well you know in Road Racing typically it’s open tire but more often than not everyone or at least nearly everyone ends up running the same tires.
Just sayin’

True, but road racing incentivizes tire longevity due to having longer races.

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Yeah, but the manic short-term performance of sprint racing drives crazy behavior.

Last time we looked at a spec brand it was going to pay out something like $5 per entry per race.

It was not enough to warrant our smaller club to pick one tire and run it. The open rule allows the guys who run RT66 or ROK or Battle at the Brickyard to run their leftovers from those events. I have not heard of anyone complaining that Racer XYZ was faster due to tire choice.