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pedroroach
2010.02.11, 07:11 AM
So I just got my first Mini-Z yesterday and tried running it on my Micro-T track that I have in the basement. The track in industrial carpet with pipe insulation as the walls.
My first question would be is it normal to have the car slip out at every turn.
The way I was driving around the corners would be to either let off the gas or give it a bit of brake as I enter, but as soon as I was at the apex and started to give a little throttle it would do a 90 degree spin out and run into the wall.
Is this a problem with the gear diff?

I have a whole bunch of hop ups coming but would like to get a feel for the car in its stock form before I go change everything. Just so I know how much they help, but are these cars drivable in their stock form?

LED
2010.02.11, 07:27 AM
You at least have to chance the tires.
If i'm not mistaking the stock cars carry 40 tires all around.
So try out some tires you like.

But to answer your question, a stock car is very drivable out of the box except for the tires.

But you should also put in some ball bearings and a carbon H-plate. And maybe a kyosho oil shock.
Those are about the minimum hop ups you should have.

Gl

pedroroach
2010.02.11, 07:37 AM
You at least have to chance the tires.
If i'm not mistaking the stock cars carry 40 tires all around.
So try out some tires you like.

But to answer your question, a stock car is very drivable out of the box except for the tires.

But you should also put in some ball bearings and a carbon H-plate. And maybe a kyosho oil shock.
Those are about the minimum hop ups you should have.

Gl

Stock are 40 deg? I bought 30 deg radials for all around. How will the radials compare to slicks on carpet?
I have the H plate, bearings and the oil shock coming in on the same order. I also have the friction dampener coming in too.

How loose should the gear diff be? I can hold the tire on the opposite side of the pinion and give it throttle and the opposite wheel will spin but when I hold the pinion side tire it just sort of locks up.

hrdrvr
2010.02.11, 08:35 AM
^ You may have a problem with the gear diff though, which can happy rather easily in a rear end collision.

I agree with LED, try out some tires. Id try the Kyosho 20 radial rears wth your 30s up front. You may also want to look into the Atomic line of tires. When we raced on carpet they out-performed all others at our track. The straight grooved, or the AW grooves were best.

pedroroach
2010.02.11, 08:45 AM
^ You may have a problem with the gear diff though, which can happy rather easily in a rear end collision.

I agree with LED, try out some tires. Id try the Kyosho 20 radial rears wth your 30s up front. You may also want to look into the Atomic line of tires. When we raced on carpet they out-performed all others at our track. The straight grooved, or the AW grooves were best.

The car was right out of the box brand new. Can you disassemble the gear diff and rebuild it? Maybe there is no grease in it? I don't think I have seen the instructions on how to rebuild the diff.

LED
2010.02.11, 09:04 AM
What you discibe is normal.
One will will spin fast when you hold the other, wnd when turn one wheel the other one should turn in the oposite direction when the spur gear is hold.
Be sure not to overtighten you wheel nuts. The wheels should be able to spin easy. There is no need for grease in the diff. You can add grease but only if you know what you are doing. You can pull it apart but i'm sure there is nothing wrong with it.

An unwritten rule also says that you should have softer tires in the rear then in the front. But that you should find out for yourself.
I've run kyosho radials 20 all round and that worked good. 30 could still be to hard.

pedroroach
2010.02.11, 09:22 AM
Thanks for the help. I'll try the tires when they come in and see if it helps with the sliding out. I just didn't expect for the rear end to swing out that much. I think I'll need the ball diff too because the gear diff unloads way too easy coming out of a turn.

LED
2010.02.11, 10:57 AM
like I said, tires first then the rest. Get a good rear tire that gives good traction and then start playing with the fronts.
My best time i ever did was actually with a complete stock car (incl diff) with alu motormount and a 96 mm H-plate.

herman
2010.02.12, 12:59 AM
welcome to the forums... all good tips here... i mostly run mine bone stock too...
tires are first priority... for me a good set of tires will account for at least 50-60% of your set up... the rest will be fine tuning... hope this helps... :D

pedroroach
2010.02.24, 08:04 AM
So I got my tires finally, 30 F+R radials.

This car STICKS to the track now. Now I need to work on the hopping issue in the back. I have the H plates now, top friction dampener and oil shock.

What would be a good setup for carpet with lots of traction now with the new tires?

I tried the medium H plate, just a drop of grease on the plates for the dampener and the stock oil for the shock. Should I be going softer or harder to overcome the bouncing? I also have the rear spring kit, with the medium spring on, a 4.5 limiter in the front with the green springs.

color01
2010.02.24, 04:58 PM
If your car sticks to the track with 30deg rears, you've got lots of grip indeed... you'll need some stiff damper springs and thick grease to get rid of the chatter. If you haven't already, sand down your disk damper parts (the disks and plate) with 1000-grit sandpaper, and when you put it back together use something like 1000# damper oil. You'll probably want more than just a drop of this stuff, I usually go for 2-3 drops of oil per disk and let it work itself out naturally (I like having the grease grooves in the disk damper disks nice and filled). Try the car out again, and if you still chatter then you'll want stiffer disk damper springs, OR you can use 3mm ID shims (rear axle shims) to add preload to the disk damper springs; that will also help increase damping.

Carpet's typically smooth so I'd say you can probably step up the spring on your oil shock to the yellow one (Kyosho springs aren't very stiff...). But you can probably keep your current T-plate and front springs, since carpet cars need to have some body roll to work right. The damping adjustment will take care of your hopping issue, no real need to look at springs.

Do you have a picture of your track?

herman
2010.02.25, 12:22 AM
So I got my tires finally, 30 F+R radials.
This car STICKS to the track now. Now I need to work on the hopping issue in the back.

nice to hear...
now go fine tune your suspension... :D
try and experiment with the different springs you got and see what works for you...

hrdrvr
2010.02.25, 07:31 AM
Check and see what type of pre-load youve got on the bottom damper spring. I had a bad habit of setting them too tight when I first started using DDSs (Disc Damper Systems), and it caused me all sorts of trouble. A good experienced racer told me to check that out when I was at my first ever big event (and had a chatter problem). Since then, its the first thing I check, and its normally the culprit. If not, try running a harder spring on top than on the bottom, and pre-load the top spring. It should help a lot.

pedroroach
2010.02.25, 07:39 AM
Thanks for the tips. I'll try those settings tonight. I have a 7 week old at home that doesn't always like to sleep. I'll try to get some pictures tonight too.

MXMRCR
2010.02.25, 09:38 AM
hi, hrdrvr is only one to mention Atomic tyres, Atomic make a specific 6 deg carpet tyre, we all use them at our club they are very very grippy but wear out pretty quick.

run them with 20 deg up front