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View Full Version : Good starting point for tires & wheels on a MR-03W MM?


mdowney
2010.11.26, 02:50 AM
I'm so confused by all the treads, degrees, and offsets for Mini-Z tires/wheels. This may be naive, but aren't the track conditions with RCP almost always the same? I don't understand why there are so many options.

Can someone please suggest a competitive set of tires and wheels for use on RCP with a US spec MR-03W MM with a McLaren body? Please include degrees and wheel offsets. I'd like to start with something decent and then experiment from there. Thanks!

cowboysir
2010.11.26, 06:01 AM
As with any outdoor track, variables are dependent on numerous conditions that allow for one RCP track to be very different from one another. Room temp, wear rate of track and cleanliness (rcp dust) are just a few of the key factors that affect initial grip and then amount of usage during a race can change the grip levels as the event progresses.

Tire wise, no matter where Ive driven i find Kyosho tires to be a good starting point for grip. 20d wide rears and 30d narrow fronts is our spec class setup and it is a very good basis to work from when checking grip levels. You can dial front and rear grip from there but you'll be decently surprised at how good a starting point they are...

Offsets depend on which year the McLaren body you're using...if its the original F1GTR from the 1996 series then they are 0offset rears and 0 or -1 offset fronts. If it's the 97F1GTR with the high downforce body addendum then its +3 rears and +1 fronts.

Mike Keely
2010.11.26, 09:31 AM
If it is the McLaren that is gray and pink that came with the MR03 then it is the high downforce body that takes the +3 rear and +1 front rims.

Kyosho also makes a 20 radial tire that has a little more grip for the rears. The bad thing about any of the radials is that when the tread is about gone the tire looses some of its grip. I like the radial better then the slicks since they have the extra grip. I am not worried about the shorter tire life being that the tires are only $4 a set. If you run a lot in one day you might go through two sets in a day. The front slick will last you many weeks if you don't use a tire truer to cut them down. Most people cut half of the front tires down so the front of the car sits lower and is easier to drive so that makes it less likely to flip over so easy. If you do true them down they will still last you two weeks easily.

The stock T bar is a weak part of the cars so I would think that you will want to buy a #4 and #5 graphite mid motor mount T bar for each car. The stock spring that comes with the car is pretty soft so a upgrade set of front white springs will make the cars much easier to drive. If you will be running the cars at half speed in the training mode you will not need the T bars and springs.

Have someone show you how to dial a lot of the steering out of the cars. If the steering will turn the car around 180 degs in one track tile the cars will be very hard for most people to drive as beginners. Put the cars all the way on the side of one guard rail and turn the steering wheel full and in each direction make each car uses most of the width of the track to make a 180 turn around.

These are just my sugestions to make this more enjoyable for all of the people driving these for the first time. Hope it helps.

mdowney
2010.11.26, 04:03 PM
Thanks guys. Those are great suggestions! The tire situation is starting to make more sense to me now.

I hadn't thought about dialing down the steering. That's a really good tip for our event. We'll be using the new EX-5UR Txs from Kyosho so we should be able to turn down the steering on the Tx.

On a related note, is that ICS USB connector ever needed? I guess it let's you tweak the speedo on the car?

Mike Keely
2010.11.26, 06:33 PM
I tried changing the speedo settings with a buddies ISC and I think the car comes with the best settings from the factory. I don't think it is needed.

bermbuster
2010.11.26, 07:30 PM
The ics also can tweak your steering and if you have gyro it can tweak that too....

mdowney
2010.12.02, 04:06 AM
I guess the next question is: how does changing the degrees of the tire effect performance? And what is "degrees" a reference to? Why a higher number up front? How do you know to pick 8.5mm, 9.5mm, or 11mm?

unearthed name
2010.12.02, 04:36 AM
degree is the softness of the rubber compound. the higher the number, the harder the rubber is. softer tire means more grip but also means more wear (you have to change tire faster). how it effect performance? well if your front tires are hard say 40 degree or above, your car won't be able to turn as fast as it is with a 30 degree tire because your front tire won't be able to grip to the track as good as it does with a 30 deg. tire.

btw a higher grip in the front tire will lead to oversteer (the car sliding out) so that's why some people prefer to use higher degree tire in the front.

for sake of simplicity in our club, instead of the diameter of the wheel, we call them wide, semi wide and narrow tire. wide for the rear tire, and narrow for the front tire. the wider the tire, the more grip the tire has since it has more contact area.

so to sum up:

higher degree tire = less grip

wider tire = more grip

mleemor60
2010.12.02, 06:18 AM
For the time being all you have to know is Kyosho 30 fronts and 20 rears. There are others but these will give you the best all around performance in either slicks or radials.

mdowney
2010.12.02, 11:59 AM
Thanks. I ordered a bunch of K20/30s. I was just trying to understand how the tuning works. In offroad tires are like 80% of your setup. I assume it might be similar with Mini-Z?

mleemor60
2010.12.02, 12:56 PM
Never tune the car to run on the tires. As they wear out the set up gous away. Find the spring rate you are most comfortable with then tune in your camber and toe settings. Again for comfort. Then fine tune with tires. Don't worry a great deal about caster at this point. As you learn the cars and how they drive with your tweaking you can then start fooling around with caster settings. Caster makes the car want to go straight or straighten up off the corner.

There are a blue million different set ups but the right one is the one that lets you drive the car comfortably.

EMU
2010.12.02, 04:29 PM
I use Kyosho 20d radial rear tires on almost all of my cars (except when running LM or F1).

For front tires, 70t or slower motors I like the ATM Slick-R 40. They have a hint of push to them, but still have good steering. It takes a little edge away from the car, and reduces scrub while steering (car slowing down due to front grip).

Faster cars I like the Kyosho 30d radials, with tread worn off.

There are a lot of tuning tricks that you can do with tires to increase or decrease grip with any given tire. If you want to reduce grip a little, glue up the sidewall to stiffen it up. To gain grip, you can put a couple grooves lengthwise in the tire (best done on a truer, but capable with a dremel or drill).

I tend to use my tires until they are completely worn. I like my rear tires just as the radial is about to wear away to a slick. If it has too much tread, I feel that the rear end is not consistent with grip.

I tune for comfort first, then start searching for speed. If I am not comfortable, then the car will not be as consistent, and in general consistency is more important than outright speed.

I recommend that you get a good variety of front tires, and use the Kyosho 20d radial solely for the rear. This way you can test what each front tire does to the handling with a constant rear. Some compounds will have more steering entering the turn, but less on exit. Others less entering the turn, more on exit... look for the type of tire that suits your comfort level. I dont change my tire compounds often when I go to different tracks, as I find that most of the time I am still in my comfort zone. I may go to a new set of f/r tires, but 90% of the time I stick with the same compounds.