KiwiMike
March 29th, 2011, 08:21 PM
This turned into a bit of an essay guys and I know to some of you I'm preaching to the converted, but this may help someone looking at getting started. So I apologize to you at the start.
I read a post recently, where someone asked a karter about what frontend geometry he was using and he stood there like a stunned mullet, not giving up any information, but a shrug of the shoulders.
Now if this guy was an LTO karter (left turn only or oval) then thats what you would probably get, as LTO is a pure science, especially if you are racing on dirt.
Asking that sort of information, is like asking to borrow his wife, they are not going to tell you.
However a shifter karter will tell you how his is set up, because it isn't such a science, as they tweak only two setups, wet and dry.
So as our BSRs perform similar to a shifter kart, I will give you a basic set up, which is guaranteed to work every time.
Toe Set Up.
Toe Setting is always set to 0, but can use increments up to 1/8" toe out.
The faster you want to go, the less toe out you use. Toe setting is done by adjusting tierods in or out and measuring between the front of the rim and the back of the rim and checking the difference.
Camber Set Up.
Camber is used to increase or decrease the tire contact patch to the road surface. Negative camber is when the tire is leaning in to the center of the frame. Positive camber is when the tire is leaning out, away from the center of the frame. With that in mind, set your camber to 0, due to low speeds.
Caster Set Up.
Caster can only be adjusted if you have an adjustable spindle set up with hiem joints. Most of us set our caster when we weld our spindle brackets to the front axle. Some shifter karts will run up to 15 degrees of caster, this helps with wieght jacking on the chassis, lifting the outside rear wheel in the corner. However it wouldn't be wise to set 15 degrees in a BSR front end as a shifter kart is only 2" off the ground and we sit 24"-30" off the ground, so natural leverage will take care of some wieght jacking. I set 8 degrees of caster in mine, so between 8-10 dregrees will be fine, but I have heard of some guys just leaving the caster at 0 and haven't had too many problems steering.
Akerman Set Up.
It pays to back cut your axle at 25 degrees from square so your spindle brackets angle to the rear of the frame. This will let you set akerman into your steering without your tie rods binding up on the spindle brackets.
I read a post recently, where someone asked a karter about what frontend geometry he was using and he stood there like a stunned mullet, not giving up any information, but a shrug of the shoulders.
Now if this guy was an LTO karter (left turn only or oval) then thats what you would probably get, as LTO is a pure science, especially if you are racing on dirt.
Asking that sort of information, is like asking to borrow his wife, they are not going to tell you.
However a shifter karter will tell you how his is set up, because it isn't such a science, as they tweak only two setups, wet and dry.
So as our BSRs perform similar to a shifter kart, I will give you a basic set up, which is guaranteed to work every time.
Toe Set Up.
Toe Setting is always set to 0, but can use increments up to 1/8" toe out.
The faster you want to go, the less toe out you use. Toe setting is done by adjusting tierods in or out and measuring between the front of the rim and the back of the rim and checking the difference.
Camber Set Up.
Camber is used to increase or decrease the tire contact patch to the road surface. Negative camber is when the tire is leaning in to the center of the frame. Positive camber is when the tire is leaning out, away from the center of the frame. With that in mind, set your camber to 0, due to low speeds.
Caster Set Up.
Caster can only be adjusted if you have an adjustable spindle set up with hiem joints. Most of us set our caster when we weld our spindle brackets to the front axle. Some shifter karts will run up to 15 degrees of caster, this helps with wieght jacking on the chassis, lifting the outside rear wheel in the corner. However it wouldn't be wise to set 15 degrees in a BSR front end as a shifter kart is only 2" off the ground and we sit 24"-30" off the ground, so natural leverage will take care of some wieght jacking. I set 8 degrees of caster in mine, so between 8-10 dregrees will be fine, but I have heard of some guys just leaving the caster at 0 and haven't had too many problems steering.
Akerman Set Up.
It pays to back cut your axle at 25 degrees from square so your spindle brackets angle to the rear of the frame. This will let you set akerman into your steering without your tie rods binding up on the spindle brackets.