Caster l blocks.


New member
What affect on a kart racing on dirt would a 6 degree left side caster block have on the handling of the kart . the right side caster block is a 10 degree . Also is there a big performance advantage having a 1/2 inch king pin instead of a 3/8 kingpin . Thanks.
flex and durability is all. 68 caster block is that stock? at any rate it affects weight jacking and camber gain. which unfortunately you may or may not want. less degree less gain / less jacking . if your on the right rear to much it could help.
We'll try to give it a shot without writing a whole chapter in a book. Caster is a huge element in weight jacking as the kart corners and controls the timing of weight jacking - which corner unloads/loads when. Rule of thumb: if you are running on a short track with tight turns you need to run lots of caster to get a better run off the corner than with lower caster. On a sweeping high banked tracks you need to run less caster to get the same effect.

Increasing caster split (the difference between LF and RF caster, 4 degrees in your case) results in a larger percentage weight loss/gain (depending on which front wheel you are looking at), basically controlling the amount of weight transfer with a given angle of steering wheel input. More caster split will tend to free up the kart because less weight is transferred to the right side tires by weight jacking.

A 1/2" kingpin is a good deal stronger than a 3/8" kingpin, so when you hit something, it will be less likely to bend - or, conversely, more likely to cause something else to bend in a collision, due to its extra strength. Other than collision performance, I can't think of any other advantage of 1/2" over 3/8". If there are other advantages, others will chime in.
Are you talking about KPI or castor? Both will affect the kart although I've never seen either really affect the outright speed of the kart. They're both more about getting the whole kart to work together.

Ltg. On the bottom of my caster block on the left side it has a # 6 stamped on it so I'm thinking that's 6 kpi On the spindle arm on the left side is a # 10 stamped on it guessing that means 10 degrees of caster On the right side the caster L block has a # 10 stamped on it thinking that's 10 kpi and on the right spindle arm there's a # 12. It's an older kart. I guess I'm wanting to know is 6 kpi on the left front good for dirt racing .
If you want to change KPI, you will need to change the spindle and the L block together. KPI is built into the spindle, the L block just allows you to adjust to the proper camber.
to better answer the question ,not knowing chassis type . a 6 degree caster block is not going to cause you to go from the front to the back. you should be fine . phantom has a 5* lf frt that is for asphalt which some have run on dirt. there should be plenty of adjustment to adapt to the conditions you run in