As the sleeves broke in they became more concentric and flat across the tread which helped some as well by giving more even grip.
So we took a look at what was going on. Racing karts have a lot of Ackerman angle built into the steering geometry. This is so the chassis can lift the inside rear wheel as the steering wheel is turned. Since Karts have no differential this lift is important to reduce inside wheel scrub and drag when cornering. The amount of lift is tuned by chassis flex. When engineering cars for Formula Drift, we learned that excessive Ackerman causes cars to spin out due to too much front drag. We figured that this was happening here. So we reduced the Ackerman to its lowest setting possible and it made a huge difference.
The kart could now actually be drifted smoothly for as long as you wanted, however, you could not run much angle and you could also not go very fast. The explosive power delivery and poor low-end power and throttle response of the racing two-stroke engine also made it hard to keep steady torque on the wheels which is important for doing smooth drifts. A cheap 4-stroke engine would actually do better here.
9 comments
do you think putting the sleeves on the front would introduce enough slip to make it easier to manage? also, dad of the year?
No, it would be really hard to control and you would still have the basic problem of not enough steering angle and too much Ackerman angle and too much front drag.
When you say “a lot of ackerman angle”, what does that mean? More inside wheel scrub or less? I am confused… Cool article!
It means the inside wheel turns more than the outside.
Haha, nice article! Looks like a fun experiment even if it didn’t work out.
This is definitely something I’ve wanted to try one I get a kart.
Thanks for this writeup, I found it to be quite helpful. I am an amateur rally racer and I’m building an electric kart to get accessible seat time between rallies. I am very keen to turn it into a drift kart.
What you wrote at the end matched up well with my own thoughts on how I might be able to turn this into well tuned a drifting machine. I will be playing around with the steering geometry – hoping that plus the insane torque from the electric motor is able to get the job done.
Would you be willing to connect briefly on this? You seem incredibly knowledgeable on the subject, I think it would help tons. I’m more than happy to share my results with you! I don’t see a way to send you a message here. Am I missing something or is that the case? If so I will give you a burner email in here. Thanks!
a few years back my son and 10 year old son and i used to play with an old margay sprint kar (mine) and an old Rup racing kart (his). both were terrible on at street drifting, but were AMAZING on grass and dirt with Harbor freight Pred motors. The instant torque and broader power band made throttle modulation sublime and even with drift slicks the Rup was a decent drifter if the speeds were low.
Funny experience: I noticed that the jacking and Ackerman was great for grass and dirt drifting on kart slicks thanks to the lower surface friction. It allowed for CRAZY angle at high speeds and awesome feints.
That’s said I have a big diameter rear axle. I flipped the rear wheels and mounted them backwards to narrow the rear track. That alone made the Kart less likely to spin out, even on pavement.
Yeah the high strung two stroke is way less than ideal for this for sure.