Tamiya mini cooper
#8101

Just starting out on mini so seeking some advice from Mini drivers. My car seems a bit inconsistent in the rear grip, Right is over-steering and left is understeering. Right turn is especially bad at the end of the straight Where the speed is thgreatest, it will always spin out. I have even adjusted the EPA such that the right is 80%, left is 103%, and the unequal-ness shows physically on the car's steering travel. I can't really reduce dual rate anymore else the car will not turn the tight corners tightly. Better, but still unsatisfactory! Before turning down, the car was over-steering both sides! Running 3200 Lipo, and did the recommended weight additions.Track is probably low-ish traction, tyres are X-patterns all around. CVA shocks with f/r blue/red or yellow.
Last edited by stocker; 01-14-2009 at 05:55 AM. Reason: Problem Solved, ref later post.
#8102

#8103
Tech Master
iTrader: (22)

I am no where near an as knowledgeable as a lot of others here but try having another look at your suspension. Make sure that the shocks are not only the same length but that they feel the same when you compress them. If they are not even side to side you can get some really weird handling.
Terry
Terry
#8104
Tech Initiate

Adding weight to my Mini was the key. After doing that I never had any traction roll problems and it handled really well. I added most of the weight to the battery inside the indentations of the Orion 2400 pack. I added probably 150g because my shell alone is 98g. Is that typical or did I put on way to much paint? What is the weight of an unpainted shell. If paint adds considerable % of weight then it would make sense to hardly put any paint on it and keep the shell light, then add the remaining necessary weight to the chassis down low.
I also only sauced the inner half of the front tires then all of the rear tires. Handling was perfect and now its just down to learning how to drive smooth 100% of the time.
I also only sauced the inner half of the front tires then all of the rear tires. Handling was perfect and now its just down to learning how to drive smooth 100% of the time.
#8105
Tech Initiate

I think really the only thing I could try to do to improve my car to my liking now would be to somehow find a little more speed in the straight. There was one or two cars that seemed to have a little more speed in the straights. I put full ball bearings in the transmission. Would a larger MaH battery pack give a higher voltage under load or would it no be noticable? Is there any kind of legal tuning that can be done to the motor to gain some speed?
#8106
Tech Apprentice

So I raced my M-03L for the first time last night (it was on carpet). There were 6 mini's running, I qualified 2nd and finished 3rd in the final. Not too bad considering it was the first time I had 'raced' any RC at all. 
The current setup is this:
Full bearings
Super mini CVA shocks (blue springs on front, yellow on rear, using supplied oil, arms level front & rear).
S-grips all round, double-stuffed inserts on front (1 hard + 1 regular), 1 regular insert in rears.
TA03 ball-diff (setup as per rc-mini, tight & a bit of threadlock applied to stop it coming loose, but with standard ball-diff grease, as I haven't got any AW grease yet).
Receiver & LiPo cutoff in rear of chassis, stock tamiya ESC on top.
Sport-tuned motor w/ 20T pinion.
HiTec 945MG servo (@6V 0.12s/60*, 11Kg/152 oz.in torque).
Yeah Racing 3200 LiPo, weight added in bumpers & battery compartment bringing car up to 1350g.
I did have a couple of issues though...
1. Grip roll, which every seems to have at sometime. I will CA glue the outside sidewalls of the front tyres for next week to see if that helps, but would it be worth fitting the anit-roll/sway bar set as well, or wait and see if the glue trick works by itself?
2. Off-throttle turn-in oversteer. The track layout had a sweeping 180* bend after a straight. If I tried to take it at full throttle the car would roll. So I tried to coast/back off around the first part, then throttle out of the bend, but every time I tried this, the rear would step out as soon as I started to turn in, and make the car spin. On a tight bend after a straight, when braking was needed, the problem didn't occur, it was only when going into a corner when braking shouldn't be needed. I tried turning the steering speed & exp. down, but it didn't cure it. Is there anything I can do to the car setup try and stop this?
P.S. These mini's are really quite fun to drive aren't they!

Those aren't white dish wheels in those pics, just standard 11-spokes, the camera flash hid the detail.

The current setup is this:
Full bearings
Super mini CVA shocks (blue springs on front, yellow on rear, using supplied oil, arms level front & rear).
S-grips all round, double-stuffed inserts on front (1 hard + 1 regular), 1 regular insert in rears.
TA03 ball-diff (setup as per rc-mini, tight & a bit of threadlock applied to stop it coming loose, but with standard ball-diff grease, as I haven't got any AW grease yet).
Receiver & LiPo cutoff in rear of chassis, stock tamiya ESC on top.
Sport-tuned motor w/ 20T pinion.
HiTec 945MG servo (@6V 0.12s/60*, 11Kg/152 oz.in torque).
Yeah Racing 3200 LiPo, weight added in bumpers & battery compartment bringing car up to 1350g.
I did have a couple of issues though...
1. Grip roll, which every seems to have at sometime. I will CA glue the outside sidewalls of the front tyres for next week to see if that helps, but would it be worth fitting the anit-roll/sway bar set as well, or wait and see if the glue trick works by itself?
2. Off-throttle turn-in oversteer. The track layout had a sweeping 180* bend after a straight. If I tried to take it at full throttle the car would roll. So I tried to coast/back off around the first part, then throttle out of the bend, but every time I tried this, the rear would step out as soon as I started to turn in, and make the car spin. On a tight bend after a straight, when braking was needed, the problem didn't occur, it was only when going into a corner when braking shouldn't be needed. I tried turning the steering speed & exp. down, but it didn't cure it. Is there anything I can do to the car setup try and stop this?
P.S. These mini's are really quite fun to drive aren't they!



Those aren't white dish wheels in those pics, just standard 11-spokes, the camera flash hid the detail.
Last edited by Toon; 01-10-2009 at 08:58 AM.
#8107

Cool! What you've done if I comprehend correctly from the pics is to rig a limited slip or a slipper clutch of some sort.
#8108

I think really the only thing I could try to do to improve my car to my liking now would be to somehow find a little more speed in the straight. There was one or two cars that seemed to have a little more speed in the straights. I put full ball bearings in the transmission. Would a larger MaH battery pack give a higher voltage under load or would it no be noticable? Is there any kind of legal tuning that can be done to the motor to gain some speed?
#8109

hi toon,
hope below helps:
1. widen rear by putting 1mm spacers in the hex drives.
2. try if you can put the esc in the rear compartment.
3. put transponder on right side of chassis, behind battery.
4. gear diff might give better acceleration on carpet. just put lots of antiwear grease.
5. blue springs rear, yellow front might help.
enjoy.
joel
hope below helps:
1. widen rear by putting 1mm spacers in the hex drives.
2. try if you can put the esc in the rear compartment.
3. put transponder on right side of chassis, behind battery.
4. gear diff might give better acceleration on carpet. just put lots of antiwear grease.
5. blue springs rear, yellow front might help.
enjoy.
joel
#8110
Tech Initiate

I was just surfing through some of the old posts and was wondering what advantages or disadvantages of having droop in the suspension can have.
I setup my super mini shocks with the 5mm spacer and have the short tuning springs. I am curious as to what effect it would have to remove that spacer and still use short springs. The ride height would be the same but it seems it would just give the possibility to have the wheels on the ground more in really hard cornering.
I setup my super mini shocks with the 5mm spacer and have the short tuning springs. I am curious as to what effect it would have to remove that spacer and still use short springs. The ride height would be the same but it seems it would just give the possibility to have the wheels on the ground more in really hard cornering.
#8111
Tech Adept

hi there,hope you are all ok,my mini is std apart from rs sports tuned motor,ball bearings and iv built the friction shock as on rc-net,we are all supposed to run like this,lipo is allowed,we run indoor on carpet,we can have any tyre as long as its rubber,we can also run any esc(would anything other than a std tamiya one make a big differense)but what iv noticed is that there are some cars that seem to get the power down better than others,im sure its not the lipo as this would make the car just spin more from the extra power(correct me if im wrong)i know they dont run std tyres,and they have always got there cars shell on (when in the pits)),would having soft tyres and a ball diff(these are not allowed) make a huge difference compeard to std tyres and just silicon spray in the diff,i was told not to put any greese in there as it will all come out and make a mess anyway,
iv raced in all sorts of class and against team drivers in ic,electric,on and off road and know its not my driving,
there were 20 minis racing in two heats and there was 3 people who were 3 laps and over 2 seconds a lap faster,then there was 17 of us all within 1 second,
there cars were very noisy from the gear box but very smooth
i hope to get a good setup and give them an ass whooping but if they are cheeting then so be it,
thanks for any advice
mark
iv raced in all sorts of class and against team drivers in ic,electric,on and off road and know its not my driving,
there were 20 minis racing in two heats and there was 3 people who were 3 laps and over 2 seconds a lap faster,then there was 17 of us all within 1 second,
there cars were very noisy from the gear box but very smooth
i hope to get a good setup and give them an ass whooping but if they are cheeting then so be it,
thanks for any advice
mark
#8112

The M03 class I run in does not allow aftermarket plugs so I am stuck with the original bullet and battery connectors. Any ideas on what I can do with the Tamiya battery connectors so I don't lose too much power through the connection? We're limited to 1700 mAH packs as it is. Thanks.
#8113

Hopefully the clear plastic on the new hpi car us not brittle like the tamiya translucent stuff. Does anyone know what kind of diff comes in it? Lets hope that we get to build this one, not another "race ready roller" aka stripped screws and poor assembly. As far as bodies, I assume the above mentioned bodies are from new tooling. The hpi miata looks like it will clear the shock towers. Hopefully the dampers are oil filled, then they'd really be undercutting tamiya

#8114

Rumor has it that a new carpet track will open in the next few months in our area. I remember seeing a few set ups posted, but am too lazy to go thru pages and pages of stuff. It looks like we'll be able to run any tires and not just Tamiya stuff.
Any tips would be appreciated
Any tips would be appreciated
#8115

I can only comment on the new track if it happens to be extremely smooth, like the one at my club.
We tend to run our cars very low. I've had great success with hard springs (blue or double white) up front, and softer springs (yellow/red) at the rear. Dampers don't seem to matter much, but I am running a heavier oil (55wt) in the fronts and 35wt in the rear.
Run your steering as neutral as possible, and if you can find them, run a lower sidewall tire, like a 55d, or anything else that will help eliminate traction roll.I usually run the rear wheels about 1mm wider (spacers) than the fronts to gain a little more rear grip, and use a little Niftech on the tires. BTW: since we're still talking about tires, the Team Powers pre-mounts are fantastic. Since I run a smaller tire, the 20t pinion is perfect. I still get great punch out of the corners, and the motor is just about topped out at the end of a 60 foot straight.
Hope that helps. If there's anything else, or anything more specific, feel free to shoot me a PM.
Jim
We tend to run our cars very low. I've had great success with hard springs (blue or double white) up front, and softer springs (yellow/red) at the rear. Dampers don't seem to matter much, but I am running a heavier oil (55wt) in the fronts and 35wt in the rear.
Run your steering as neutral as possible, and if you can find them, run a lower sidewall tire, like a 55d, or anything else that will help eliminate traction roll.I usually run the rear wheels about 1mm wider (spacers) than the fronts to gain a little more rear grip, and use a little Niftech on the tires. BTW: since we're still talking about tires, the Team Powers pre-mounts are fantastic. Since I run a smaller tire, the 20t pinion is perfect. I still get great punch out of the corners, and the motor is just about topped out at the end of a 60 foot straight.
Hope that helps. If there's anything else, or anything more specific, feel free to shoot me a PM.
Jim