tire not getting hot

7

71 chevy

New member
I took the kart to the track last night. weve had heavy rain, and the track was closed for the weekend, so no rubber on the track.

however, I was running mg yellows(old) with about 13psi cold and after 6 laps (50 sec laps) the tire temp was only 120degrees (6.5 hp clone honda) and the kart was sliding around every corner.

this is already more than the mfg suggested pressure. what should I do to get more heat into the tire?
 
Raise the seat, narrow the front and rear. Suggested pressure is just a suggestion for regular conditions that you are not experiencing, try 20 PSI and see what happens.
 
Are you saying you just dont have enough grip. Tire temp is pretty meaningless imo with how many variables their are. A low hp kart on a green track simply is not going to make much heat, especially running in the evening. Given the conditions I'd guess you were off your usual times just like everyone else would be. It's not unusual for the track to be off 2 full seconds at times after a lot of rain on tracks that big
 
Freezeman said:
Raise the seat, narrow the front and rear. Suggested pressure is just a suggestion for regular conditions that you are not experiencing, try 20 PSI and see what happens.
Click to expand...

I will try the 20psi and see what happens.

gary10 said:
Are you saying you just dont have enough grip. Tire temp is pretty meaningless imo with how many variables their are. A low hp kart on a green track simply is not going to make much heat, especially running in the evening. Given the conditions I'd guess you were off your usual times just like everyone else would be. It's not unusual for the track to be off 2 full seconds at times after a lot of rain on tracks that big
Click to expand...

Thanks for the info. Im new at this and what I heard/read was that tires work best between 175-205 degrees.
Its good to know it may be the green track/low hp. Last time out, before the rain , I was running 15psi cold and it was working pretty well but I dropped it yesterday after reading the recommended tire pressure from the mfg(11.5 +- 3).after 10 laps and a bunch of sliding I raised it back to 15psi and it worked much better but still did not get hot - yesterday was the first time I ever checked the tire temperature.

I plan to go back out sunday morning . Saturday night will have some heavy racing so there will be some rubber put back on the track. Im curious to see how this affects the heat that goes into the tires.
 
I would think that number is incorrect. I believe my tire warmers get them to about 150 and that is about as hot as i would think they get in race conditions. The suggested pressures you are seeing are not intended for use on a clone. Likely aimed toward high hp tag 2cycle engine. You will like run a couple more pounds. 11-12 on a good track in summer is a good start.
 
Better yet just throw the pyrometer in the toolbox and focus on chassis changes like freezeman mentioned. This isn't NASCAR or more simply oval racing. Turning both directions makes it useless. Feel free to pm me with any setup questions
 
gary10 said:
Better yet just throw the pyrometer in the toolbox and focus on chassis changes like freezeman mentioned. This isn't NASCAR or more simply oval racing. Turning both directions makes it useless. Feel free to pm me with any setup questions
Click to expand...

thanks man, ill be sending you a pm

Familyman said:
Our base psi is 17, Wet or cold jack it up 5
Click to expand...

thanks for the info. what tire are you running?
 
71, I run nearly the same program, most of us use the cheap to free ~2/3rds life MG Yellow take offs from the TAG and shifter karts. I run the pressures up until the tires start picking up tire "fluff" from the track....looks like your tires are melting, then back pressures down until they clean up. On cold winter series days I've been at 20 psi, hot summer days down to 11psi and I'm scaling at around 465#'s with a big block.
 
rkcarguy said:
71, I run nearly the same program, most of us use the cheap to free ~2/3rds life MG Yellow take offs from the TAG and shifter karts. I run the pressures up until the tires start picking up tire "fluff" from the track....looks like your tires are melting, then back pressures down until they clean up. On cold winter series days I've been at 20 psi, hot summer days down to 11psi and I'm scaling at around 465#'s with a big block.
Click to expand...

thanks for the info. Im at 482 lbs so not too different. I plan to try a range of pressures to see where it works best. do you have any information on tire temp?
 
I don't have any info on temp sorry....I start high and work my way down on pressures. As the tires heat up, they will overheat and start to go out if you have too much pressure and you'll notice a smeared melted rubber look on them.
On the below freezing day I ran 20 psi, it was actually too much, but the tires got hot fast on the warm up lap and allowed me to pull away from the rest of the pack still sliding around on cold tires at the start. With a couple laps to go they were overheating and starting to smear and fling rubber, but I'd built up a 7+ second lead by then and no one could catch me.
 
Peak tire temperature is hard to capture as it occurs during cornering and cools from there while running down the straights. By time you pull into the pits and get out of the kart and get the temps the tire has cooled a lot. The temps are best used to check for differences across the tire patch and at each corner of the kart in order to try and gain a better over all balance of the kart.
 
If as you said tires are old and you haven´t used them for some timne try 1st some laps at higher pressure like 17 to get them ready so they loose some of the top surface.
 
update- I ran the kart today with 19psi cold in the tires. 25 laps. it still took forever to come in and my best laps were 19,20,and 21.
tires were hotter to the touch but i forgot my darn gauge so i couldnt get a reading.

im beginning to wonder if my pressure gauge is faulty- im sure its not but ill have to check it against another gauge

one would expect the tires to be working early with that much pressure in them
 
At that weight with mg yellows I dont even know how its possible to run your best laps that late in the run. How old are the tires and do they have much rubber left? If u put on a brand new set with 19# and drive it 100% their is no way you run your best lap after lap 5 under normal conditions.
 
gary10 said:
At that weight with mg yellows I dont even know how its possible to run your best laps that late in the run. How old are the tires and do they have much rubber left? If u put on a brand new set with 19# and drive it 100% their is no way you run your best lap after lap 5 under normal conditions.
Click to expand...

I got them with the kart so I dont know their age but I will assume they are quite old. I dont see any wear marks on the tire. durmeter punches between 55 and 60 usually.

do you suggest new tires will be the cure? I will buy a set once I wear these ones OUT. someone suggested to me that old tires are better for learning finesse, which is what Im doing right now.
 
I suggest you start your mission to buy a set of new tires and wheels. That way you can always put your old worn out tires and wheels back on in case you feel like learning finesse at a slower pace. Learn what new tires feel like at least for one run so then you will be able to confirm what tires that are old and worn out feel like. All the adjustments you make to the kart and tire set up is quite different when using old and new tires in order to make them turn the fastest lap possible with them.
 
You must log in or register to reply here.
Back
Top