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vesahyp
2010.09.10, 11:41 AM
Hi,

I bought a used mr-02 2.4ghz a week back for 80e. It's mostly stock with ball bearings, carbon fibre(?) t-plate and aluminium steering knuckles. I also got a x-speed v motor as a bonus (haven't tried it yet).

The problem i'm having is trying to change the pinion to a smaller one (came with a 9 spoke pinion installed). It seems anything smaller than that 9 either skips or doesn't even hit the diff properly. I'm glad i tried to rotate the wheels before actually hitting the track. The diff is stock i assume (white).

Do i need an adjustable motor mount or different plastic 'feet' for the motor to rest on (the ones i have read t7)? If so, are these sold separately?

Thanks in advance!

EMU
2010.09.10, 12:28 PM
You need different shims to space the motor, or a mount that has such adjustments for the motor you are using. You can try to speak to people around you that have cars, and see if any have the shims you would need. Many people use aftermarket mounts, so they should have the spare shims.

vesahyp
2010.09.10, 01:42 PM
Thanks for the speedy reply!

Not having the manual or previous experience with a mini-z, can you say what this t7 means on the shims i currently have? Should i be using a 7 spoke pinion gear?

I'll be ordering a package of stuff from the UK (i live in Finland, all mods are stupidly expensive here) so i'll add an aftermarket motor mount to the list of things to get.

EMU
2010.09.10, 02:00 PM
Which motormount do you have? RM or MM? If your not sure, the RM has the motor to the rear of the axle, and the MM has it in front (RM = Rear Motor, MM = Mid Motor).

The RM are easy to shim and adjust without the stock shims, the MM need the small spacers on the side which are specific for the amount of teeth on the pinion, and are designed for use only with the 44t (standard) spur for the ball diff. If it says t7, it is for use with a 7t gear. But you have to make sure that both sides of the motor get the same size spacers.

benmlee
2010.09.10, 02:19 PM
Sounds like you just got the car with no shims for the motor. If so, you are stuck to one size gears. Like EMU said people should have those shims laying around.

Here is the link to the manual. It will tell you what shim to use for what gear.

http://www.kyosho.com/eng/support/instructionmanual/mini-z/miniz_racer-awd.html

vesahyp
2010.09.10, 03:27 PM
Thanks all, this has cleared up the issue.

It's a stock MM motor mount and it seems i'm stuck with the 7t pinion for now.

Looking at the mount options i'm leaning towards the PN racing 94-98mm LCG Motor Mount. It's reasonably priced and (the V1) doesn't require drilling the motor as far as i understand.

I'll be honest, i love fiddling with car setups. Am i missing something obvious from my shopping list?

* Tie rods for toe in/out
* Adjustable diff (the stock isn't adjustable not counting different greases?)
* Springs (front/rear)
* T-plates
* Tires

I'd also be interested in fiddling with camber but i guess that requires the a-arm? From what i've read, people are quite divided when concerning the a-arm front so i thought i'd skip that and concentrate on the basics before dishing out for that.

Thanks to everyone for being so nice. Love these forums, could spend days reading up on things. Every day i understand more what people are on about :)

Pierro
2010.09.10, 04:45 PM
Hello!

I'm not sure the PN pod does not require the motor to be drilled. you'd better look carefully before ordering it. I know the atomic 94/98 V4 (or previous) can be used with drilled and non drilled motors.

For camber, you can simply buy knuckles. At the beginning I'll go for a set of plastic knuckles with various angles and see wich one you prefer before buying an aluminium pair. Atomic or 3 racing make those kits I think...

As other guys told you, you are stuck with the 7 and 8 pinion at this time. (7 and 8 use the same shims) If you find a club or another racer, he may have those shims for you. Almost every racer has those and don't use them anymore.^^

For your list, everythings fine. Try get some different degrees in tires. (always softer on rear) And maybe a friction damper if you can.

EMU
2010.09.11, 04:12 AM
Look at what tires the guys around you are using on the track. That is a good judge of what works. And you should try to stick to similar compounds of what others use around you because it gets laid into the track, and gives you better grip when using the same compound. Going to a different company tire that is equal grip rating may not have as much grip as the tire that is most used on the surface.

I am pretty sure that PN does not make a motor mount that does not use the screws to hold the motor. Atomic, 3Racing/R246, Eagle Racing, and Kyosho all make alloy mounts that are compatable with non drilled motors. If you are not restricted to use Kyosho motors, then you may want to get a mount that uses the holes and get a motor as well. You dont have to and shouldnt get the fastest motor. But something that is a little quicker than the box stock would be good to tune and see what the tuning does. PN 70t or Atomic Standard would be good choices. ATM discontinued the Race USA motor, which was a great handout. A little faster than the PN70t, but not too much. It still feels like stock class racing, but with a little more speed.

Tjay
2010.09.11, 06:46 PM
Here's what I would recommend to get first:

-PN70 turn motor. It's a great motor for only $9!!
-buy pn v1 994-98mm lcg) mount for $20
-Tires (If you want it to last forever, buy PN25 with PN6 radials. Mine is already slicks but the car is still hooking up. Its still the same tires I had at FPR in May then I used it at NY in June and then now at FPR again. I have no plans on changing it and it's still hooking up perfectly fine).
-H-plates (soft, med, hard) PN, ATM or kyosho
-Damper Plate System <-- MUST!

This is it for now. As time goes by, you'll eventually going to invest into springs, polished kingpin, toe bar, ball diff, etc... but what I have posted above is probably what you'll need to get going when running/racing on RCP track.

If you feel the need of buying A-Arm and Tri shock, I say save your $ and buy a MR03.

* I know some of you guys will comment on my last statement but if this guy is a new driver. Let him enjoy this car that he can learn to drive smoothly. Then when the time is right, definitely try the A-ARM/Tri shock.


Thanks all, this has cleared up the issue.

It's a stock MM motor mount and it seems i'm stuck with the 7t pinion for now.

Looking at the mount options i'm leaning towards the PN racing 94-98mm LCG Motor Mount. It's reasonably priced and (the V1) doesn't require drilling the motor as far as i understand.

I'll be honest, i love fiddling with car setups. Am i missing something obvious from my shopping list?

* Tie rods for toe in/out
* Adjustable diff (the stock isn't adjustable not counting different greases?)
* Springs (front/rear)
* T-plates
* Tires

I'd also be interested in fiddling with camber but i guess that requires the a-arm? From what i've read, people are quite divided when concerning the a-arm front so i thought i'd skip that and concentrate on the basics before dishing out for that.

Thanks to everyone for being so nice. Love these forums, could spend days reading up on things. Every day i understand more what people are on about :)

vesahyp
2010.09.12, 05:03 AM
Thanks again for the insights. I'll add a damper plate system to my order. I'm definately going to stick to the MR02 for now as i'm a beginner with the whole mini-z class.

Our local track is RCP (layout: http://kotisivukone.fi/files/hippz.kotisivukone.com/.album/1283775819808_1_large.jpg) and they have the MR03 cars for hire if i want to test them at some point.

My biggest problem with my car is that at full throttle the engine tends to cut out, then cut back in at full speed when you let go of the throttle a tiny bit. It does this even when you hold the car in the air and squeeze the throttle to full. I've tried messing with the throttle offset (? on the controller the up-down buttons) but the feature hasn't gone away.

I'd really appreciate any ideas as to what could be wrong.

EMU
2010.09.12, 11:46 AM
Nothing is wrong. The ASF MR02 board comes with Virtual Inertia enabled. VI gives some gas as you let off to let the car roll as a larger car would when you release the throttle. I dont mind it for slow motors, but faster motors I cant stand it. You can use the ICS USB adapter for your computer, or handheld ICS adapter to adjust this VI setting and turn it off where it will respond exactly with what throttle input you are giving.

The KT-18 transmitter also has a bug, where if you pull the trigger down too far, it cuts off. You can put a little tape around the handle where it can restrict the amount of trigger that you can pull. This will not effect top speed, as you can still adjust the hipoint of the trigger... But it may be why you cut out...

vesahyp
2010.09.12, 12:19 PM
Ok, thanks for that info. I'll put a piece of rubber on the controller so i can't pull it to 100% throttle. It seems that opening the transmitter cleared up the problem at least momentarily.

vesahyp
2010.11.23, 04:47 AM
Thanks again all for the input.

I put up a few first pictures of the chassis here if anyones interested:

http://mini-zracer.com/forums/showthread.php?p=398448#post398448