I am wondering what the Ka100 longevity of chain, sprocket, and driver? I am seeing heavy wear on them. My first race I made it to the last race and last lap on a used clutch driver was totally worn and threw a chain. 2nd race weekend with a new driver and new sprocket, I made it day 2, I went off and pulled over and my sprocket was done. 3rd race weekend new sprocket, last race was a standing start and felt the rear tires slipping and threw a chain. Looking at the sprocket looked pretty worn and decent amount of wear on the driver. Any thoughts why this might be happening? I have tried to adjust the chain guard as there is a little rub but it seems to be on the sides which I stretch it out, but wondering if perhaps that is part of the issue.
Not a KA guy but sounds like misalignment.
I also hear 2 stroke guys throw new chains on every race at higher levels
Something sounds misaligned or you’re using some subpar chain lubricant.
I run standard chains, non-o-ring, and can get literally like a dozen weekends out of them. I can get almost a season out of a sprocket and driver too. I might throw a new chain on for a race weekend, but the used chain goes in my toolbox for practice days.
I would definitely check the alignment of the rear sprocket with the clutch driver using a straight edge or the laser tool that some kart shops sell.
I would also try adjusting the tension on your chain, I’ve found with the KA100 that running the chain too loose (like you may have run on an old Yamaha) tends to wear the teeth on the back edge in a sort of “sawblade” shape.
The driver should easily last over a dozen events if aligned correctly. The sprockets may wear more or less depending on what brand/supplier you’re using. The cheaper ones, made from softer aluminum with a thinner coating, can wear much more quickly on the higher horsepower 2-stroke karts. I’d splurge for the more expensive ones that use better materials with the better anodized coating.
Definitely an issue somewhere. We run full seasons on a single chain, and I replace the drive sprocket maybe once every other year. The rear sprockets last forever as long as you don’t hit a curb.
Get a good chain laser alignment tool. Also, lube the chain between each sessions. Chain tention is important as well, not too loose, not too tight.
Something doesn’t seem correct. I have run KA at the club level for 4 plus seasons and still have the same driver. Its about due for a change but I would avoid aftermarket drivers, they are known for issues. The chain should last a season as long as you don’t have an issue. Sprockets are also a year or more as long as it is aligned. I have been using Bel-Ray Super Clean chain lube applied after every session. If you see any shiny aluminum flakes around your drivetrain that is a sure sign of misalignment.
I think I must be running our chain too loose. We have damaged 2 drivers this season and go through chains much much faster than you guys. I use laser aligner, so that isn’t an issue. Also use Motul C4 chain lube, so it’s a known quality product.
Something to look into more…
That was my last race of the year, I have 2 different chain aligners that I am going to try next year the courtney concept and a generic one I found online. I might also try Chain Monkey Tensioning tool, to make sure the chain has the proper slack.
Chain tension can be a pain sometimes. I try to have it so when I push up on the chain, it’s not quite touching the cage around the clutch/drive sprocket. This also depends on the mount you use. I use the Odenthal 5 degree mount.
Using the stock OTK mounts. They rock a touch on the cross bar weld. So the tension changes quite a bit as you tighten or how you tighten.
Always tighten the front clamp first, which should tighten the chain. Then it’ll slack off as you tighten the rear clamp. I also like to use the engine stop as a fine-tuning adjustment for chain tension. If the chain is too loose or too tight, I just crank the engine stop bolt a few turns forward and back to adjust it. It also helps on the KA to take the rear springs off the pipe, otherwise it wants to hold the engine in place when you’re moving it.
I got tired of stripping the threads on the OTK mount for the engine clamps.
May have done that a few times this season. 
Trading in the old OTK and likely going CRG to align with team mates. The OTK has 2 years and 35 race weekends on it with a second frame having about 13 weekends on it. Otherwise would be putting an ORP on it.
I use the Odenthal on our OTK with no issues.
What brand of sprocket do you use?
I use RK because it’s the only one they sell near me
No wonder the new model will add a new chain tensioner
For front sprockets I use the IAME one and for rear sprockets I use literally whatever I have.
Chains I use RK usually.
Adding a couple of questions as a KA (Jr) newbie here…
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Used kart I bought had only 3 of the 6 bolts holding sprocket on to carrier. Owner said “that’s all you need at this power level”. Looking for a second opinion on that one…
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Advice for chain was “o-ring for practice, non-o-ring for racing” because of the additional friction from o-ring chain. Is that additional friction meaningful?
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I asked about sprocket guards, answer was “only if your climbing curbs on a sprocket 78T or higher”. This makes sense to me I think, but wanted to bounce off y’all…
Some would say what I run is overkill, but I never have driveline problems caused by hitting things and the bottom of my frame looks pretty great considering how much I aim for curbs. My theory is that even with a small sprocket size, there are certain angles that can allow something below to penetrate into the area (e.g., not everything you meet is going to be in the shape of a horizontal plane the neatly meshes with the horizontal plane of your kart frame).
I personally run two types sprocket guards no matter what sprocket size I’m running:
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The plastic round kind of sprocket protect that hug the sprocket. Though cheaper looking, I like the plastic because it flexes a bit so when it strikes something and absorbs some of that impact and isn’t so jarring.
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I also run this style guard at the same time (it bolts around the frame rail in the back, and hangs just below the sprocket):
I guess if was running a truly tiny sprocket I might take off the plastic guard and just run the bolt on frame type.
That frame guard is cool, I haven’t seen that one before!
Kind of like the OTK protector for their big brake disk kit.
3 bolts is totally fine. Use a sprocket guard if you are running a larger gear or if you want more peace of mind. I jumped a wheel this season and the landing bent the sprocket and ended my race but with a guard it may have saved it.
O-ring is totally unnecessary in KA. I have regular chains last for multiple weekends no problem.