Ka100 Budget analysis

Hi all,
I am considering making the jump from racing the Briggs 206 at the club level to the IAME Ka100 at the club and regional level. I am planning out the costs, and I have most of the info I need to know. However, I am curious about several things.

First, How many club races can a set of tires last in the Ka100? In Briggs, we can go 3 club races without seeing a drop in performance.
Secondly, per race, how much should I expect to spend on replacement parts to be competitive? (I.e. Carb/Clutch parts that get worn out)

Third, if I plan to race regionally, (including unrelated test and tune days) how much should I plan to spend on replacing general parts? (I.e. crash replacements, etc.)

Finally, how much should I plan to spend on practice tires? (I plan on and already practice about every weekend, or every other weekend.) Would I have to be buying a new set per every day of practice?

Any other info I need to know would be appreciated!
Thank you, I appreciate any help!

What tires does your club run for 206 and for KA? If they run the same compounds, then wear probably won’t be much higher in the KA compared to the 206.

I do a carb kit and new plug before each race weekend, mostly just as cheap insurance, but I’m sure you could get 2-3 club weekends out of each if you wanted. I know there are plenty of people out there who are taking theirs much further. A carb kit is something like $30 and a plug is maybe $5. That’s about the only engine related maintenance I’ve done. I’ve not had to touch the clutch on my KA.

Depends on how much you crash :slight_smile: Generally higher levels do bring out more aggressive drivers, but it’s a difficult thing to quantify. Ultimately, I wouldn’t expect your regional-level parts budget to be much larger than your club-level parts budget.

Again, we’d probably need to know what compounds you’re running to give a more accurate estimate. For regional/national events I would plan on having a new set for the race weekend, and also having at least a lightly used set (1 club weekend max) to practice on for each regional weekend. Most guys at regional/national events I go to have a new set to switch to for practice, and then a new set is required for qualifying on Saturday. But you could get away with a lightly used set for practice if you’re on a budget.

The biggest cost difference between 206 and KA is probably going to be in engine time. A 206 can go multiple seasons without needing to send it to a builder, but for a KA you’ll probably want to get a top end done after 8-10 hours of run time, and a bottom end after 15-20 hours. For most this usually translates to a top end sometime in the middle of a season, and a full rebuild during the offseason.

I have 1 season of racing KA at the club level and can attest that these motors are reliable and consistent. As you point out tires are going to be your main expense. As for how they compare to what is used on 206 varies from track to track. Also some races may require a spec tire that you will have to buy for a specific race. My track used MG reds and the wear and constancy was excellent. As far as how that compares to 206 might be tough to compare but I would guess it to be similar.

As for parts in a season of 11 races and I think 3 track days I didn’t have any motor related expenses other than a carb rebuild a few times and new filter screen, mostly just preventative maintenance. I think I replaced 1 chain and 1 sprocket and 1 spark plug. I cleaned the clutch twice and greased the roller bearing. Some recommend cleaning the pipe of carbon build up once or twice a season.

Accounting for crash items is always a concern. I would have extra axles, a spare steering shaft, tie rod ends but all that should be the same regardless of class.

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I think Jake and Robert pretty much covered it, but you should also consider fuel/oil costs when comparing the 2 engines. Our club series uses pump gas for the 206 which here in southern California goes for around $3/gallon currently. The 2 strokes however run on ms98 which is upwards of $16/gallon. Over the course of a season this is definitely something to consider.

Running in the KA class for the last two years, here is what I have done/experienced.

Tires - wear depends on the track and your driving style. I typically buy new tires that I use for qualifying at a regional race, and then use those tires until the next regional race. Regional races are usually 6 to 8 weeks apart with 3 or 4 club races and practice sessions. I stretch it out because it’s a little bit of a cost savings, and training. We’re not really fighting for podiums and most of the time that needs to be gained is in the driver, not the tires or setup.

Engine parts - I need to get better at the some of the preventative stuff, so I rebuild the carb every 2 or 3 months before I see drop off. I’m going to try to get better at doing before each major race. Plug I change every 6 to 8 weeks, right around each regional race. I think the reeds need to be checked and replaced around 5-6 hours on the motor. I let this go for a long time, and started to see performance drop off around 12 hours. Also, every 2-3 hours I would clean the header and remove the carbon off of it, and I would also remove the carbon off the piston and clean the combustion chamber. Top end rebuild should be around 12 hours, bottom end won’t need to be done until closer to 60 hours.

As far as crash repairs, that all depends. We had gone 3 years without any major damage, and then last year we had one crash that cost almost $1k alone.

Thanks guys for the responses. In both my club series and the regional series that I’m looking at, they use the MG Evinco Blues.
Ryan, I’m jealous that they allow y’all to use pump gas on the 206 because where I’m from, we have to buy ms93 which for 5 gallons ends up costing $100 every time we need fuel. I do need to factor in fuel and oil for the cost. Do y’all have to mix the oil and fuel together, or is that an onboard system like the 206?
I’m also curious about the clutch. In 206, we have springs and pads that need to be replaced relatively often. Is the clutch somehow different in Ka? I’m no mechanic, but at find it hard to see how the clutch might be different. Other than that, engine maintenance seems to be low on the Ka.
As for engine rebuilds, is it better/cheaper to go longer between rebuilds or shorter? I have actually heard things all across the board on this one and I’m curious about what y’all have to say.
Thanks for the help!

You’ll mix the oil and gas together yourself prior to pouring it in your gas tank.

I’m less familiar with 206 clutches, but on the KA I basically just leave it to my builder to look at. Someone else might be able to offer more details, but they are relatively hands-off, especially compared to the 2-cycle karting engines of ages past.

Going longer between rebuilds will be cheaper, and you’ll absolutely hear tons of different opinions on how long to take them. The only risk you really run with stretching it out too long is eventually running down on power. So far the KA has been an incredibly reliable package. It would probably be worthwhile to ask a local builder their thoughts, particularly whoever you plan on taking it to when you do need work done on it. That’s who I ultimately end up listening to when it comes to my engine.

Either way, a KA will definitely require more frequent rebuilds when compared to a 206 - just want to make sure you factor that in while budgeting the step up from the Briggs.

We use Evinco Blues in our club and regional races as well.

The clutch on the KA is springless. It is a disk with 3 pads on it and open on one end. I got through 2 season on one of my motors before I needed a new clutch.

And for top end and bottom end rebuilds, it’s probably best and cheapest to be a little longer, or until you feel like there is a power drop off. Top ends can easily make it 12-15 hours between rebuilds. I haven’t made it to need a bottom end yet, but most top engine builders will check everything and suggest when they need to be rebuilt.

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I’ve got 24-ish hours on my bottom end and intend to stretch it another top end before rebuild. That said I did easy bottom end maintenance myself (main bearings and seals) at 20 hours. My bottom end will be pretty straight forward in that it really focus’s around rod and thrush bearing replacement.

Rpm should be considered in top end frequency. We turn KA’s right at 16k at our home track and both my brother and I both had pistons break at around 8 hours. I’ll be pulling down top ends betweeen 6-8 hours depending on how much of that time is at my home track. Places like GoPro and Née Castle where you’re not spinning it as high you may be able to get more time on the top end.

My clutch was used when I got it and I put a full season on it and it still looks solid. I’ll prob throw one in the spares pile for this year so I have one at the ready but right now this same clutch has plenty of life left.

The clutch is very reliable as it is the same clutch from the x30. If they do fail they crack one of the flex points. I keep a spare on hand but have not seen any issues.

The main concern I am aware of over top-end rebuilds is the piston has a pin that keeps the ring from moving. This pin has been know to fail and allow the ring to move and then it catches on a port and causes big problems. As a precaution top-end rebuilds are suggested around 12 - 14 hours. I think someone pointed out your operating RPM’s and the more you run probably should rebuild sooner.

Where are you racing?

For fuel, IAME specifies 98RON with oil at 20:1 (6 oz/gal). 93 AKI premium pump gas is 98RON / 88MON. Klotz Techniplate oils satisfy JASO FD, which is the strictest specification for oil for high-RPM two-strokes.

stock timing spec per the manual is 2.1mm and stock squish is generally higher than min race spec due to head gasket thickness.

Not saying 93 octane absolutely won’t work but when optimized for race conditions the squish usually gets tighter and the timing is more advanced. Probably best to run a 98 octane (MS98L is spec fuel for many organizations that race KA) to provide a margin of error when considering detonation.

I am looking at racing in Texas’ Regional series; I also race in the GHRS in Houston. For both we are required to have VP MS98 in KA. Now that y’all bring up engine specs what kind of stuff are y’all doing to the engine settings to keep it competitive?

So, you plan to run the Texas Sprint Racing Series. We’ve ran that the last few years and were one of the first to run the KA in the series. Were you at Speedsportz for the last race?

It’s not a tough motor to keep competitive. Everything listed above would keep it competitive without much more work.

Not sure how you mean this. Are you referring to tuning, preventative maintenance needed or what is done on rebuilds? There are several threads dedicated to the KA and they are all work searching and reading.

Yes, I was at the last speedsportz race last Sunday. I was the #616 Tony Kart Lo206 Senior that seemed to always be in the back hunting people down despite having top 5 pace :roll_eyes:. Robert, I am kind of referring to the tuning, although I am also curious about preventative maintenance. I’m Mostly curious about the engine stuff because someone brought up head gaskets and stock timing or something like that. I will look at those threads about Ka tuning. Thanks for any help!

We were there as well. My daughter moved up to run in the senior class for the first time at that race.

Don’t worry too much about timing or head gaskets, etc. While they are things you can do to change the performance, most engine builders have their way of adjusting it. I don’t think there is a “magic” setting that makes any one motor better than the other.

Is the lady that’s been taking pictures lately, associated with you?

Yep! That’s my mother. If you’re interested in buying pictures, they are here: https://mimivance.photoshelter.com/archive
More pictures from this last race will be up soon. In that race the Ka senior class alone had more than all of the Lo206 combined, which was I though was really interesting. As for the engine maintenance stuff, I’m glad it’s not that bad because I’ve heard crazy stories about what they did back in the Rotax days.

Cool. I saw some of them the other day, and that there were more to be posted.

KA has really grown here in Texas in the last 2 years. I think there may be a few LO206 racers that will convert over. While the initial cost may be more, the maintenance is very easy and not anywhere near the level of the X30. There’s already something like 22 KA seniors signed up for the entire TSRS series. I am sure we’ll have more entries at each race for those that are 1 offs or miss the cutoff (2/14) to sign up for the entire series.