[jt colegrove]

JC, can you send a picture of the tire balance stand to me?

 

jtcolegrove@gmail.com

[jt colegrove]

Depends on whether you’re using the GPS data, which is calculated based on your change in position, or the accelerometers.

 

Accelerometers are noisy, and it’s easy to get distracted with shock/peak values.

GPS data is nice and smooth, but won’t always tell you the full picture.

Your peak values are going to depend on the corner, track surface, temperatures, tire wear, etc…

Your best bet is to look at your data all the time and develop an understanding of the performance envelop of your kart with you driving.

In my TAG I’ve seen GPS values as high as 5G in the banked turn at Boston F1 outdoors.  4G+ accelerometer data isn’t out of the question either for peak values.

In theory, a lighter kart like a JR should be able to produce more lateral acceleration than a TAG, which should produce more lateral G than a shifter.  This is due to the CF of a tire decreasing as normal load is increased.

[jt colegrove]

10 helps the pipe clear the bumper better.  I had one, and got rid of it.  My X30 runs cooler with a cast mag mount.  I use sandpaper on my rails and it stays put.

[jt colegrove]

Dan, I’m also 6’2 and I had to work a bit to find a decent seat position this year.  I’m on a compkart, but the same things might hold true for you.  I’ve experienced the same issues as you where on turn in the front outside tire gets overloaded by excess jacking, due to a combination of my height and too much camber.

I had a T11 copy in the kart to start and I feel like i sit on top of the seat and have to use so much energy to stay in the kart, so I swapped to a T8 standard.

My seat is just over 5MM below the rails, it picks up a decent amount of rubber.  It’s also reclined a touch.  I have wound up almost 1″ behind where J3 had me start with the seat.  Between getting the seat into the right area and pulling caster out of the kart I’ve found the front end to gain a lot of grip.  Before, as soon as you’d turn in the rear inside would jack immediately and the front outside would overload quickly due to the height of my body’s CG transferring more weight than needed.  Mid corner off would usually be oversteer because as soon as I’d touch the gas the rear inside would slam down and flat slide to the exit.

Get your seat low, and be gentle with the throttle on exit.

[jt colegrove]

Front wheelspeed is more useful than rear wheel speed.  If you’ve got front, you can really accurately identify wheelspin on corner exit with this math channel:

 

(front wheel speed/(engine RPM/1000))

[jt colegrove]

Colin,

 

It’s something that’s coming down the road.  I think they got so backed up that it wasn’t something that was finished in time for the launch.  Keep watching the firmware releases.

[jt colegrove]

Hey Tom,

I have a used MyChron 4 with GPS05 unit I’m getting rid of.  It logs things like your engine RPM, temperature, GPS speed, lateral and longitudinal acceleration, and creates track maps.

If you had one, it would be really easy for you to give us lots of information to troubleshoot your problems and get you going in the right direction.

A MyChron 4 costs 350 new, and the GPS is 300.  I’ll sell them both shipped to your door for $340.

[jt colegrove]

I have a Manning, and another that I built.  I had Comet hone / fit a new piston, and had them re-assemble my crank with a new rod kit.  Aside from a very poor package job on the return trip, comet did a great job.

I re-assembled the motor after they did the crank and cylinder, and it’s dead nuts with my MMK motor at big places like NJMP.

[jt colegrove]

Scott, I don’t have any left at the moment.

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