powersteer
Well-Known Member
Re: Best semi-slick?
adjust the kart to fit you, not the other way round
totoseow;628696 said:
adjust the kart to fit you, not the other way round
Best semi-slick?
- Thread starter kuvesh
- Start date
Re: Best semi-slick?
All roadcar tire manufacturer pressure recommendations are only ballpark +/- a few psi and they're usually cold or barely warm pressures, certainly not hot.
Only the more performance oriented tires have a recommended hot pressure and the tire manufacturer still doesn't know everything about the car that the tires are mounted on. You have to find your own optimal within the ballpark. Driver must already be ballpark good. Run a bunch of laps, varying pressure either side of recommended hot pressure. Put markers on your tires, look at onboard video or photos of your car on track to see how much the tire is rolling. Look at your lateral and longitudinal accelerations, feel out the stability of the tire, check that wear is ok. As long as you're not under 90% of recommended hot pressure (if any) and the performance indicators are maxed within reasonable pressure window, with no crazy rolling of the tire under lateral load, or weird long term wear, then that's 'optimal'.
For many factors there are is no optimal, no easy answer, have to realize it all functions as a system and test. And not just guess and go by memory, but have a plan, follow it, measure, make records. Data..
MachoMan;626186 said:
All roadcar tire manufacturer pressure recommendations are only ballpark +/- a few psi and they're usually cold or barely warm pressures, certainly not hot.
Only the more performance oriented tires have a recommended hot pressure and the tire manufacturer still doesn't know everything about the car that the tires are mounted on. You have to find your own optimal within the ballpark. Driver must already be ballpark good. Run a bunch of laps, varying pressure either side of recommended hot pressure. Put markers on your tires, look at onboard video or photos of your car on track to see how much the tire is rolling. Look at your lateral and longitudinal accelerations, feel out the stability of the tire, check that wear is ok. As long as you're not under 90% of recommended hot pressure (if any) and the performance indicators are maxed within reasonable pressure window, with no crazy rolling of the tire under lateral load, or weird long term wear, then that's 'optimal'.
For many factors there are is no optimal, no easy answer, have to realize it all functions as a system and test. And not just guess and go by memory, but have a plan, follow it, measure, make records. Data..
Last edited by a moderator:
Re: Best semi-slick?
Single speeds geared high enough can. 6 speed shifter karts can go 0-160-0 in under 10 seconds, 0-100 under 3 sec.
See video below.. the karts look light but they're roughly 80-95kg flying around. 170-190kg with driver, depending on class...
[ame="http://www.youtube.com/watch?v=IB8Flty3yzU&feature=related"]YouTube - Kart crash compilation[/ame]
F3 cars have diffs. Cars are not designed to jack so much weight. If they had so much caster and scrub radius, it would take a lot of power to turn the steering wheel.
Can't generate the loads that karting does without million dollar operations and racecars (F3 or higher, GT1 or SGT, LMP at certain tracks). It's why F1 drivers train in karts in the off season. If not for the average dumb consumer, the companies chasing after their dollars, and the misguided culture it's grown for decades; most everyone would be karting, few to none would be driving cars around on tracks.
MachoMan;628751 said:
Single speeds geared high enough can. 6 speed shifter karts can go 0-160-0 in under 10 seconds, 0-100 under 3 sec.
That's why you have full suits, rib guards, neck guards, which help a bit. You still don't want to crash though. Have to be respectful of other drivers and not just lean and push your way around.. else it could be you flipping. It's good in the sense there is a real potential penalty to pay for being reckless or imprecise.
See video below.. the karts look light but they're roughly 80-95kg flying around. 170-190kg with driver, depending on class...
[ame="http://www.youtube.com/watch?v=IB8Flty3yzU&feature=related"]YouTube - Kart crash compilation[/ame]
Karts have no differential. Keeps weight, complexity, and cost down. Free up the inside wheel by unloading it with weight jacking via lots of caster and scrub radius.
F3 cars have diffs. Cars are not designed to jack so much weight. If they had so much caster and scrub radius, it would take a lot of power to turn the steering wheel.
Can't generate the loads that karting does without million dollar operations and racecars (F3 or higher, GT1 or SGT, LMP at certain tracks). It's why F1 drivers train in karts in the off season. If not for the average dumb consumer, the companies chasing after their dollars, and the misguided culture it's grown for decades; most everyone would be karting, few to none would be driving cars around on tracks.
Last edited by a moderator:
Re: Best semi-slick?
Local track KF2 karts reach peak speeds of only about 100 km/h. Rotax a little less, KF1 a little more. For higher speeds at bigger tracks / tracks that allow shifter karts, have to go into Malaysia or wait for Changi.
Also most incidents occur in wheel to wheel racing, so running solo and not pushing limits, the risks are much lower.
Fav part of the video is from 2:36 to 2:43. The poor dude is being efficient, using literally every last inch or track width, high frequency low amplitude steering corrections, hauling ass through the sweeper....... and then can't avoid the guy who has spun out and parked on the track... man what bad luck.
Local track KF2 karts reach peak speeds of only about 100 km/h. Rotax a little less, KF1 a little more. For higher speeds at bigger tracks / tracks that allow shifter karts, have to go into Malaysia or wait for Changi.
Also most incidents occur in wheel to wheel racing, so running solo and not pushing limits, the risks are much lower.
Fav part of the video is from 2:36 to 2:43. The poor dude is being efficient, using literally every last inch or track width, high frequency low amplitude steering corrections, hauling ass through the sweeper....... and then can't avoid the guy who has spun out and parked on the track... man what bad luck.
Last edited by a moderator:
Re: Best semi-slick?
If one were to make a compilation of all the worst car crashes around, people watching would be scared too. But those who have seen the typical open trackday, and even the typical touring, GT car, LMP car race, will know that those incidents are rare and mostly avoidable if the drivers decide not to push it.
Which is why you should kart more to see that it's not as crazy as it seems. The learning curve is steeper than in cars, but once past the first month or two usually everyone is nicely settled in by then.
Have to be logical about it mate
If one were to make a compilation of all the worst car crashes around, people watching would be scared too. But those who have seen the typical open trackday, and even the typical touring, GT car, LMP car race, will know that those incidents are rare and mostly avoidable if the drivers decide not to push it.
Which is why you should kart more to see that it's not as crazy as it seems. The learning curve is steeper than in cars, but once past the first month or two usually everyone is nicely settled in by then.
Have to be logical about it mate
Elite
Well-Known Member
Re: Best semi-slick?
While on this topic, here is a very good documentary from BBC on the early years of F1 -- very sobering reminder
Part 1 -- http://youtu.be/hy7gmd8XXAA
Part 2 -- http://youtu.be/TBTMEyvhR_w
Part 3 -- http://youtu.be/LxGaejdBb4M
Part 4 -- http://youtu.be/JT8c5yfjR7w
Shaun -- See you this Sunday same time same place on the track and don't forget to update my gear ratio
While on this topic, here is a very good documentary from BBC on the early years of F1 -- very sobering reminder
Part 1 -- http://youtu.be/hy7gmd8XXAA
Part 2 -- http://youtu.be/TBTMEyvhR_w
Part 3 -- http://youtu.be/LxGaejdBb4M
Part 4 -- http://youtu.be/JT8c5yfjR7w
Shaun -- See you this Sunday same time same place on the track and don't forget to update my gear ratio
Last edited by a moderator:
Re: Best semi-slick?
JW, don't be a puss.
Even 12 year old girls kart. And they are fast, and still alive after all this time.
[ame=http://www.youtube.com/watch?v=iNkZcbWWUtA]YouTube - SKC - Feature on female drivers Gabriella Teo and Manon Maistre[/ame]
jwwu;629093 said:
JW, don't be a puss.
Even 12 year old girls kart. And they are fast, and still alive after all this time.
[ame=http://www.youtube.com/watch?v=iNkZcbWWUtA]YouTube - SKC - Feature on female drivers Gabriella Teo and Manon Maistre[/ame]
