Flipping rear tire in between races

[stangmx13]

Flipper a rear tire in between races, good or bad?

Ever since i started doing 4 races in a day, ive flipped my rear tire after 2 races at tracks that favor one side. AutoClub punishes the left, Buttonwillow the right, Vegas the right, etc. i prob started doing it trying to maximize tire life because my tire wear wasnt great and because i couldnt notice a diff in grip between races. but those 2 things have def changed now. my tire wear is some of the best in my class with WERA and i can feel all the subtle grip changes.

for my current tires, Dunlop GPA Pros, grip decreases after the first race. the 2nd race isnt too bad. then i flip and grip decreases a bit more but stays constant for the 3rd and 4th race. the drop off with Dunlop's latest DOT seems to be greater than their prev tires, so its all more noticeable.

so what do you think? is that extra heat cycle from the flip causing the drop off for the 3rd & 4th race? would the tires lose that bit of grip no matter what i did and i'm just wasting time/effort doing the flip? what is your experience?

 

[Mick-e]

From my experience from flipping tires you need a session of use for the tire to settle in.
I would not be keen to race on a tire that had just been flipped.
Have you tried running a tire the same for all 4 races? How does that feel for grip?
I would flip my rear at Willow Springs, but I'd run Friday all day one way, and flip the at the end of the day and run Saturday practice. I'd put a new tire on for races.

 

[stangmx13]

i cant rem the last time i didnt flip a rear tire after race 2. maybe at Buttonwillow on a cooler raceday when i chose to run the Med. grip isnt bad for the 3rd or 4th race. but you know, we always look for something extra when racing.

ill likely not flip the rear tire next time out. i just want to hear other's experiences before then.

 

[Lazerus]

I haven't ridden Dunlop's in years, but your symptoms sound similar to when my tire pressure was slightly too high. Great wear but grip would diminish towards the end of race one (as pressure spikes). Between coming down a few psi and working with mctech, three or four races and it's more hooked up than it used to be the last few laps of race one :.02

 

[stangmx13]

Dont worry, I'm not racing w 23psi off the warmers like Dunlop suggests at trackdays and on their website :laughing. Grip suffers if I go any lower, I've tested it.

The one funny thing about multiple races and tire pressure is the numbers are never consistent. Put a warmer on a new tire for an hour, set your pressure, and race. Come in, let the tire return to warmer temp and the pressure is now 2-3psi higher. Of course the warmer wasn't able to heat the entire tire, air, and wheel as well as racing and ambient has prob changed. So do u let out some air or leave it... I'm sure there are lots of opinions. I usually return the tire to my pressure, but not always.

 

[Lazerus]

I usually set them cold and double check off the warmers, then monitor how their feeling as I'm riding then how their wearing. Unless something weird is going on in either department I leave them.

 

[rob linders]

When Tyler was racing the SV, we ran Bridgestones. The weekend he set the SV track record, he went out with new tires in the first race and ran a 1:27.19. In the 2nd race he backed off and ran a 1:28:??. He said it was sliding so we flipped the rear. He ran a 1:27.21 in the 3rd race, but said it was pretty sketchy. He also said if he had new tires, in the last race he was pretty certain he could have made it into the 26's.

When he club raced on the 600 for 2-3 rounds he was on Pirellis and CT Racing was big on flipping and would do it without complaining for free, so we did it. After we decided to try AMA we switched to Dunlops and they didn't seem to want to flip them, so I don't remember if we ever tried it?

Regarding pressures we would run 19-20 in back, and 36-38 in front hot. Not sure why Dunlop gives the other pressures that didn't work for us or many others in the AMA paddock? Unfortunately, it took us a few rounds of chasing problems in the front end, before we learned its ok to go above the 33-34 we originally ran. These pressures are with Dunlop GPA's from 2012-13, not the newer style used now.

 

[stangmx13]

thnx for the recap ^^. seems like flipping vs not flipping works either way.

the new Dunlop DOTs are still using the same pressures. ive been racing on 18-20 rear for about 3 years. but it took me until i made it into the MA paddock to figure out 35-37 front.

i think Dunlop recommends 33/23 because they are safe numbers. the advantages of higher in the front seem to be necessary only when the rider is trailing really hard and 20 or less in the rear will tear fast without good rolls-on. trackday riders dont usually accomplish that.

 

[elskipador]

Dont worry, I'm not racing w 23psi off the warmers like Dunlop suggests at trackdays and on their website :laughing. Grip suffers if I go any lower, I've tested it.

you're going higher?!?!? @ ama/moto-america pace i've never ran higher than 21psi, hot off the warmers & no lower than 18psi.

 

[stangmx13]

you're going higher?!?!? @ ama/moto-america pace i've never ran higher than 21psi, hot off the warmers & no lower than 18psi.

nah. i meant that if i go any lower than where im at, grip suffers. our numbers are the same. i think prev advice directly from u helped me to find them :thumbup

 

[budman]

I think your problem is not enough cash.

:laughing

Whatever it takes to go faster is what you need to do Robert.
I bounced a check for tires knowing it was likely I did not have enough funds. When it happened I knew I was done racing. Never raced again.

So not whatever exactly. More like whatever it takes and you can afford.

Keep rocking. :thumbup