AR1 Seat Position

[Richard Gray]

Can someone please give me the correct/recommended seat position for an AR1X? I have searched the web, but nowhere is the info on the older AR's available except the following and I don't know where to take the seat to tank measurement :

SPACERS (SEAT) SEAT TO TANK AXLE TO SEAT SEAT STAGER
AR-1 1.0" to 1.25" 1.0" to 1.5" 8.0" to 8.5" To the left .5"
AR-4 1.25" to 1.5" 1.25" to 1.5" 8.0" to 8.5" To the left .5"
R-832 1.5" to 1.75" 1.5" to 2.0" 8.24" to 8.75" To the left .5"
R-932 1.75" to 2.0" 2.5" to 3.0" 8.75" to 9.0" To the left .5"
CR-932 2.0" 3.0" to 3.5" 9.0" to 9.25" To the left .5"
AT130 1.25" to 1.5" 1.0" to 1.5" 8.0" to 8.5" To the left .5"
TO32 1.25" to 1.5" 1.25" to 1.5" 8.5" to 8.75" To the left .5"


NOTE:

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The stager measurement means that whenever you are measuring the front parts of the seat, that the right side measurement is .5" longer than the left. This causes the seat to be staggered to the left and compensates for engine weight. Also to increase front bite, move the seat forward and the rear of the seat up. Too increase rear bite, move seat back and the rear of the seat down. Be sure that the bottom of the seat is level with the bottom of the frame rails, or slightly below, before drilling holes into the seat. For more or less grip, add or remove seat struts before moving the seat. (All measurements are for Birel standard seats). Use the further back options if you are running the Bridgestone tires and for Vega or Dunlop, move the seat forward and up.

Thanks, Richard Gray (club racing with my grand-nephew)

[Garry Lobaugh]

FIrst have you had your driver drive the kart? The AR 1 is about 8-10 years old and not in the current production mode. There is no magical answer. Start with the base settings as described for an R30-- a current comparison model. But then, invest in a driving school. The biggest gain for the driver is testing and instruction.

As we have our first 2000 laps completed, we can then start toworry about tuning the chassis as opposed to the hand/eye co-ordination of the driver.

In my 20 years of experience, just drive the damn thing, then lets start seeing if there is a problem. Tire compound, track surface, climate and more imporantly the body of the driver have a far greater impact on the whole equation than does some magical set of numbers of seat placement.

Here is an example: we re confirmed again this weekend that the AR28 kart is the very best kart ever in the Birel history for a light weight kid. It allows body weight transfer better for the light guys and increase performance by .7 tenths of a second on a 47 second track. I know dads that would pay $10,000 worth of motor bills to just get a .2 tenths edge.... we did it by a simple chassis test. $350 labor, $350 chassis rental.

All I can urge you to do is to get the time in the seat, then start making changes. Light driver, move the seat up vs the frame rail. Put the seat in the R30 prescribed position. The AR 1 has a narrow front end.. vs the R30.. the kart worked good for the low horsepower classes( honda and Jr. sportsman KT 100) The narrow front end allowed the driver to turn in with ease and to point and steer the kart through the corner.

Fire away if you need further information.. but just keep testing.