Castor on 1 1/8" chassis

Cakalac

Member
Have you guys played with castor on the 1 1/8" chassis? I know the weight transfer is slowed down on the thinner wall tubing naturally so would not running less caster transfer that weight faster to help the kart handle or even create some bite. I am on 9LF 12RF at 375. 60L 46.5N 68X. I was thinking about trying 7RF and 10LF to see how if felt. I know it changes my camber as well and I've considered that. I run diff tracks and was thinking about playing with caster to see if I can find another tenth or so. I know most guys say leave it alone and work on tires. Yes, I know tires are the key...however I found out this weekend at the Big O that more are using that tuning mechanism that most think. I run all grip level tracks but I'm not sure there are any really "high bite" tracks I run.
 

Bumpy

Member
I think you are backwards on UR tho'ts.
IF the 1 1/8" chassis is slow to rotate/transfer then increased caster would increase the speed of rotation/transfer.
More caster will 'dip' the RF and raise the LF, rotate weight off the LR and onto the Right side quicker at entry.
 

Cakalac

Member
I think you are backwards on UR tho'ts.
IF the 1 1/8" chassis is slow to rotate/transfer then increased caster would increase the speed of rotation/transfer.
More caster will 'dip' the RF and raise the LF, rotate weight off the LR and onto the Right side quicker at entry.
You are right I did have it backwards...thanks for clearing that up. So less caster would be for less grip which on the tracks I've ran lately haven't been high grip at all or close. I think backing caster off will help with that. I believe I'm on the high end currently at 9/12 and this chassis came from a current pro factory driver that ran higher grip stuff more often. I don't run those surfaces often. I'm more low to medium bite...
 
High bite track LESS caster, lower bite MORE, bigger tracks less, smaller tracks more, close split more weight transfer, open split less weight transfer.
silly question! is less caster like 7-10 where more caster is like 10-13? still a 3 point split and close split woul be like 7-9 and more split me like 7-12, just examples, trying to get the correct terminology. hopefully that makes sense
 

XXX#40

Member
backwards sort of on the close and open split, depends entirely on which side you change to open or close the split.
 
I've never raced dirt, so I'm not commenting from any experience other than Sprint racing. Less LF caster, it seems to me, would mean less weight transfer off the LR tire, and that would be great, if the stagger was right. So why so much RF caster? If you changed the camber 1/2°, how much does that change the corner weights? Dirt karts have changed so much over the years, I wish I knew more about it!
 
I've never raced dirt, so I'm not commenting from any experience other than Sprint racing. Less LF caster, it seems to me, would mean less weight transfer off the LR tire, and that would be great, if the stagger was right. So why so much RF caster? If you changed the camber 1/2°, how much does that change the corner weights? Dirt karts have changed so much over the years, I wish I knew more about it!
Depends on type of kart, and tires. Some karts will change more than others, and also how much of a change depends on what tire you are using. Just too broad a question for one answer given the amount of variables.
 

Bart

New member
Has anyone tried reverse castor. More on left than on the right. Iv heard of ppl doing this but never tried it myself. Does anyone have knowledge? Curious minds want to know.
 

Yakattack

Member
I would also add depends on what kind of engine you are running...
I know some of the bigger 2 and 4 strokes... your set up changes quite a bit...
 
I did a drawing, with my CAD/CAM, of a spindle. I then rotated (copy) the whole assembly by 1/2°, 7 times. 3 inches from the pivot point, the spindle moved .024" between each rotation. Kind of arbitrary, I was just guessing at where the inside edge the tire would be. The closer you get to the pivot point, the smaller that number would be. If someone wanted to tell me where the inside edge of their tire is, from the pivot point, and how wide their tire is, I could be a little more accurate. Knowing this number, people might find it a little easier to adjust their cross when adding/subtracting camber.
 
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