I don’t know a lot of people that actually tune with toe. Usually it’s something you set and leave unless track conditions change to an extreme level (like rain).
Toe-out will help initiate turn-in, correct. Toe-in will increase stability. I can’t think of a single reason or any time we’ve ever run toe-in. Excess toe will increase scrub and tire wear.
Like I said, most people I know set the toe and don’t really use it to to tune that much.
That said, I could see where extra toe out could be a good thing in cold weather to help heat up front tires (much like DAS).
To add to this discussion, I know after making any other change to the front end you will have to readjust Toe. Camber, Caster, Track and Ackerman changes will effectively move the spindle around changing the Toe as well, so you have to compensate for those changes.
I have seen many references to "X’ mm, inches or degrees, but nothing on where they were measured from. In the case of Degrees, it seems pretty straight forward, because it measure the rotation on a fixed axis. Where as a conversion from degrees of an angle to a distance depends on the length of the radius (mind wanders back to Trig Class). Most Modern Alignment Machines go by Degrees for this reason. Without some sort of Angle gauge, you are left with a tape measure. So, where do you measure from? Inside of front rim to front rim or center-line of tire to center-line of tire? Each location would equate to a different measure of distance (mm or x/x inches), because they are a different distance from the pivot point.
Secondly, I have always understood Total Toe is not the difference in Toe from forward measure to rearward measure, but rather difference in measure from perfectly parallel (0* toe) of the forward change only. Using center-line of tire as an example. 0 Toe means the measure between the front of the tires is equal the measure between the rear of the tires. 2 mm of Toe-Out should equal 0 Toe measure + 2 mm. At least that’s how every video I have seen on Sniper adjustments describes it. 2 mm Toe-out is equal to 1 mm out per side.
If I am wrong here, please enlighten.
Caster and camber adjustments shouldn’t really affect toe. Like I noted, I almost never tune with toe adjustments, but I do make camber and caster adjustments regularly.
To help the original post, I found these videos very helpful in conceptualising kart tuning. It’s very top-view and the presenter articulates each topic very well.
On the contrary, when making Alignment adjustments you may have the set Toe close first, but you always make all other adjustments before locking-in your final Toe adjustment. Lets take camber for example, if you change camber positive or negative from 0 you are effectively tilting the stub axle up or down. Assuming they are level with the ground, that tilt will force the fixed tie-rods to pull the Toe further out. Similar with Caster, by tilting the spindle/kingpin forward or backward, you will pull the Toe further out as the tie-rods become no longer level with the ground. Now most people will likely make Track/width adjustments with spacer on the end of the spindle, there is also some play using the eccentric rings on the kingpin. Say you had both arrows such that camber and caster were the same, but rotated them 180 degrees. Essentially you widened or narrowed the width, which again would affect Toe.
Now because steering geometry can have an affect multiple angles as it moves, you have to first make sure toe is at least close. Make all of your other adjustments, then set your final Toe. Cars are even worse due to multi-link suspension setups, as angles change with suspension travel too. Thankfully Karts do not have that, so best to always set “Final Toe” last.
Same idea repeated around 10:58 mark…
I wonder if the trade-off is worth it? Drag the tire and heat it up, or let it roll and figure some other way to heat it up?
I also wonder; if you toe the right front out 1/8 inch, doesn’t that drag just compensate for the pulling to the left caused by stagger? It would be interesting if there was some way to mark the position of the steering wheel to see if it was in the same position while on the track.
In Sprint racing I used to set the toe-in at 1/16, (each wheel 1/32) just to compensate (take up) for the slop in the front end geometry. In the 70s we didn’t have the great front end geometry of today’s karts.
You guys are the experts on this, I’m no dirt racer, but if it was me, I’d have both wheels rolling straight ahead, at least until it was proven, by me, that something else was better.
A few years back, an excellent karter named Nick Firestone (who also raced in the Indy 500 a couple of times) wrote 24 articles over 24 months with 4 - 5 topics per article. In one, he measured his toe on the stand and then, with his son’s help, measured toe again on the ground while sitting in the kart. His toe went from approx. 0 on the stand to a total of NEGATIVE 3mm (by sniper) with his weight added. He races shifter so I assume a 32/32 mm frame like a CRG Road Rebel. So he changed from barely any on the stand to 1 1/2mm positive each side to get “a little” positive when racing. As with TJ, another excellent racer from whom I bought my new CRG KT2, Ron White, recommends +2mm toe each side on the stand.
I have checked both camber and toe in and out of the Kart. Both changed slightly. I guess it depends on the flex across the front yokes and the angle of the tie-rods compared to the ground.
Greg is right the degree to which it changes will be different depending on a number of factors, but the underlying fact is it DOES change. Your toe will toe in and camber will go more negative. I always keep this in mind when setting my kart up on the stand
Nick’s site was really good from what I recall. Looks like he stopped working on it in 2017.
James do you have a link to that site? Can’t find it…
It’s dead, I had to go to way back machine
http://web.archive.org/web/20170504172450/http://firestonekartinfo.com/
I have read the different opinions about the front toe-out setting of the chassis and the Praga Dragon you can go for 2 mm out each side.
Because of the construction of the chassis the spindles tend to go to toe-in position,when you get in the kart(the C’s are leaning backwards)
So you always go for toe-out.Another factor is the front bar,if you drive without the front bar you can go to 3 mm each side,the chassis flexes in the more in the waist.
The rain setting,if you experience pushing go to 5 mm each side,at the same time you can widen the front track.
What can you guys tell me about setting toe-out for corner entry vs setting ackermann?
Also how do you guys go about setting the camber?
Just measuring the tire temperature (in, middle, out) and reading the tire profile, or do you also adjust this based on how the kart is handling in corners? Too tight / loose?
Toe-out will give more aggressive turn-in. Baseline is around 2mm toe-out for most karts.
I use camber as a fine-tuning adjustment to control how the kart is transferring weight or wearing the tires. I don’t measure camber that often, I just set the pills to their neutral setting and adjust relative to that. If the kart is wearing the tire’s inside shoulder excessively (a little uneven wear toward the inner shoulder is normal), I might go for a bit more positive camber. Positive camber can give the front more grip through the corner, and negative will slow down turn-in a little bit. Negative also heats up the tires quicker, which can be a good thing for qualifying or short runs or cold weather.
Thanks for your feedback TJ.
The Kart is a Spring, so keep in mind camber settings are relative to your weight. If you are a heavy guy, then once in the kart it will naturally camber negative a little, so like TJ said start at neutral and adjust as needed. I am a big guy, so I usually set slightly positive to get a more neutral setting once in the kart.
Toe is relative to the track you are driving. If its tight and twisty, then a toe out setting will help with turn in, but reduce top end on the straights. If the track is long and flowing, then sacrificing a little turn in will help maximize your top end through the faster sections. Its a trade off.
One at a time. Toe in; in my day (70s) things were loose. We set about 1/16 toe in. With today’s karts, as tight as they are, I doubt you need any toe in.