Thats pretty cool thanks

For tyres on asphalt, I'll be running Ulti tyres out of the packet, how low should I let them wear down before changing them?

I know the larger tyres have better grip for asphalt, but not sure what the approximate changeover point should be?

Thanks.

Not been smart, but run them as low as possible avoiding the chassis scrapping the ground.

Depending on the track, if it's bumpy, you may want need to run a ride height of greater than 4 to 5mm as an example. Some chassis have a limited ride height adjustment so your tyres needs to be larger to maintain minimum height.
Also tyre wear is a factor. You need to find out the life of the tyre. They may shed 1mm a race and by the end of race 2 they are too small to maintain minimum ride height so the chassis doesn't bottom out.
With the Ulti, the wear rate is different between the J compound and the Z for the rears.
Were running at the Newcastle GP this weekend with JS and ZS on the rear. The Associated 12r5.2 has a minimum tyre size on the rear to avoid scraping.
I've taken 1mm of each tyre hoping to get 2 races a set. Ill find out soon.

At your track, the ware rate will be different.

You can PM me if you want to talk about what ive done to prep the tyres.

Hi Ian, I agree for your first practice I would just run them straight out of the packet. That will help you find the ideal race tyre diameter whilst learning the car. Use practice to throw a couple of sets at the car to get them into that ideal range.

It does depend on the surface but you will probably find once you get to 41mm the car will be going slower and not just due to the smaller tyre diameter.

Opening a can of worms, my first time racing 17.5 on carpet, how many sets of tires would one need for a race event such as IIC 2016? Not trying to be ultra cheap, but also not blowing the the bank here.

Cheers Chris, the car was great with the ulti's out of the packet. So I've no issues about running them like that.

Most guys I would guess will run 3-4 sets total.

I would guess that the guys who are sparing no expense will use the 4 they allow for qualifying and mains and another 2-3 in practice.

The XR10 Juststock will power up and work with a 1s battery but it will only run the servo at about 67% of its normal (6 volt) speed. For example a Futaba 9650 has a 0.11 second/60 degree speed, at 4 volts (average voltage for a 1s pack) it would only run around 0.17 second/60 degree because there is no built in voltage booster like there is in the HW 1s ESC.

Hi Adam,

I've been running the XR-10 without a booster and the servo is plenty fast. Didn't really notice a difference compared to other cars.

I am going to try a booster for the heck of it though just to see.

Maybe see ya Sunday!

For the IIC they are limiting tires to 4 sets. Which is great in my view. At the MHIC the top racers were running 1 runs. A racer from my track used over 10 sets at that race, between the club race, practice, qualifiers and main. So, in the end, it depends on the race, and on how good you are to take advantage of 1 run tires. If you are not competing for a spot in the A, no reason to run the 1 runs in my book.

True, but at the IIC I think they are requiring you to run the 2 seeding rounds out of the 4 sets as well. Going to be nice to see people worry about tire wear and conservation.
Man I wish I could go to that race. My hotel partner backed out and I can in no way afford to do it alone, lol.

You are correct, it's 4 sets of tires for 7 runs. I'm not 100% sure how long the seeding runs are though, I believe I heard they are only 2min runs?

I believe so. If this works at the IIC, I hope all the races do this. This will be the best way to do spec tires in my opinion. And it will be another thing to plan ahead for and allow different strategies on tire use.

Nah, seeding is a full run

I still like the idea of having maximum number of pairs rather than sets, allows a person to go even farther into tire strategy. Maybe five pairs for one end of the car and three for the other. My dislike for WGT was sets of tires always left plenty of rears in the tire supply but no fronts.