Advice for running an X30 coming from 4-stroke

I raced 4-stroke Hondas (GX200) in Canada, from 2003-2009. As far as I can tell, this is very similar to the Briggs 206 class. I have since moved to the US and got into running an X30 at Go Pro Motorplex. It is the best thing I’ve ever driven. And this the best site I’ve found for information on karting.

I am running a CRG KT11. I am unsure how old it is. The tag on the rear crossmember has 08 on it, so I assume it’s pretty old. I considered it in decent shape to start out with. After a few test days, and three races, I think I have somewhat adjusted to how to drive a 2-stroke, which I had no real understanding of coming into this. In my most recent race, my best time was 4 tenths off the fastest lap of the race, which I was very surprised to see. We run MG yellows.

My issues:

  • There are bumps on the entry to turn 1, and the entire kart hops and it feels as though all four tires come off the ground. I feel helpless, and having a good apex/exit depends on how the kart settles back down from this entry. None of the other corners are like this at all, it is much easier to enter them consistently.
  • I can not get up to speed in qualifying or the first laps of the race. I realize this is probably from my driving, rather than the kart setup. Most of my confusion is from the first point I brought up, but I figured I would present this issue as well.

Lacking any understanding of 2-stroke setups, I have been guessing at setups for this kart. A decade ago in 4-strokes, I settled on running the front at max width all the time and adjusting the rear track width to change how much the inside rear lifted. I decided to put myself in a box with this kart and fix my rear track width at 55", as it seems to be common to run your rear as wide as you can. An early test was running the rear ride height at max or min. Minimum (axle up, chassis down) was clearly faster and easier to drive. I run one seat brace on each side, to the top of the bearings, and I have yet to experiment with different configurations. I have a CRG M20 axle. When I was starting out, I felt more comfortable running with the center axle bearing tight, and I’ve left it tight for now. However, I haven’t tested that recently, now that I am a couple seconds faster. It didn’t really make sense to me to run without the center bearing, when I felt like the kart was four wheel hopping in the air.

The previous paragraph ended up being about the rear of the kart, so this one is about the front. I am not very familiar with adjusting this, as I said, I only really adjusted rear track width when I ran 4-strokes. I’m at maximum front width, with 17mm spindles, and CRG wheels. Both the top and bottom caster/camber adjusters have the spindle bolt all the way back. On the kart stand the camber is about 0 degrees, and the toe is 1 degree in. I have tried adding caster by moving the lower adjuster forward, in the direction that made the camber more more positive. I feel like I understood this adjustment, and found it to be useful depending on how much grip the track had. The only thing that I have felt that maybe helped the issue with bumps into turn 1 was adding the front torsion bar, and putting it in the stiff setting.

Besides messing with chassis adjustments, I’ve tried backing off and braking earlier into turn 1, but I’m still extremely inconsistent and just can’t get the kart to settle down. In the last race, I started to experiment with the same braking/lifting off early, but partially staying on the throttle. Resting my foot on the throttle didn’t seem to hurt anything, but wasn’t necessarily better either. I’m sure I wasn’t doing it right, but I did start to wonder if there was something to that technique.

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Welcome Jonathan and thanks for the kind words. Two questions…

  1. do you have a little video we can look at?
  2. does the kart seem noticeably worse at that turn?

Hi Johnathan,

It’s strange, although I’ve felt the bump in turn 1, I’ve never had an issue with it upsetting the kart. Here’s a video of me from a few years ago at GoPro that might help:

Maybe it’s just a matter of finding that sweet spot? There definitely is something to maintaining some foot input, as you’re going to find that a kart is generally more stable if there’s braking or acceleration happening, as you’re putting force through the kart and keeping it loaded. So that’s a valid technique in some cases.

Regarding setup, unless you’re running into a specific problem, I wouldn’t worry too much. Being 4 tenths off is pretty good, so given that you’re probably running on older equipment, I would say you’re close. I would play with little tweaks on track widths and stuff like that to see if you can squeeze another tenth or two out of it, and then I’m sure if you can dial in turn one, that’s another tenth. It sounds like you’re fairly close to a neutral setup, which is good. That probably means your driving is overall pretty consistent, and you’re driving competently.

I noticed you stated that you had 1 degree of toe in. If in fact you do have toe in, it can make a Kart extremely darty in a corner. Dependent upon our weight I would safely suggest 2 mm total toe out.

You need to set the toe 1-2 degree out. I am running the same exact chassis but with a my09 leopard. Granted i’ve only tested/tuned 2 race days so far and am further off pace than you but am running similar settings. Being 4 tenths off pace you’re in good shape, keep playing with it.