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Old 01-03-2013, 07:45 PM
  #18076  
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Do you use anything special to prevent side to side motion with the rear sway bar? I find there's quite a bit of slop on both the m03/m05.
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Old 01-04-2013, 01:18 AM
  #18077  
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Originally Posted by Granpa
You might want to look at it this way. A mini is front wheel drive. Adding a lot of droop will increase the weight shift to the rear of the car. This is exactly what you don't want in a FWD. You lose front grip. What you're thinking may be just the ticket in a 4WD TC, but not for a Mini.

Here again, just my opinion, but drive out of the corners is an over rated quality. Corner speed is much more important. If you're getting around the corners with good speed, the forward momentum will decrease the tendency for diffing out. If you have good corner speed, ultra tight diffs are not necessary and flat cornering cars w/out aero do not have good corner speed.
Ok, fair enough. My thinking was that when you are trying to get out of a corner, the inside wheel breaks traction. Allowing that wheel to drop down a bit would keep it gripping.
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Old 01-04-2013, 02:07 AM
  #18078  
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Hi All, Happy New Year.

Haven't touched my minis in a while. I think 1mm ~2mm of droop would be good, to allow the suspension to work.

Attached is my excel file of Mini information. Hope it helps someone.



p.s. Besides car setup, the biggest improvement I got from minis was to learn how to use the brakes.
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Old 01-04-2013, 03:57 AM
  #18079  
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Hi Joel,

good to hear from you again, and that you´re back on Minis!
Did you also finish your tryouts of the M06 on your homepage?
Would be interesting to hear about your conclusions, and if you were competitive to the FWD Minis on your hometrack.

I´ll have a look on your sheet for sure, as I need to balance out a bit my M05...

BR,
Matthias
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Old 01-04-2013, 05:08 AM
  #18080  
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Hi Matthias,

Sorry to disappoint, but I haven't touched my minis in over a year (mini racing died in 2012 in my area). But for slow motor racing, the M06 is very good on the starting grid (I could get a 2 car headstart even before the fwd get off their starting line).

I think that motor on the very rear is causing a pendulum effect on corner exit, and I never liked the M06 when I last drove it. Could not get it as fast as my favorite M04.

Trick with the M06 is to ensure you get good qualifying position, blast away at the start and never have to dice with a fwd. Cause in bump racing, the M06 always seems to spin out.

Tight track with lots of rubbing racing, it will lose out to fwd. And in strong motor class, fwd seems to dominate (as we need brakes in corner entry).



p.s. Forgot to answer your question. In my track, if using Tamiya Lightly tuned motor rules, my M06 was very competitive. In fact, the M06s eventually turned in faster lap times. Medium size asphalt track. But a big factor is the bumping in racing.

In open motor racing (any motor, a 4.5T is legal), I used a FWD M05.
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Old 01-04-2013, 10:24 AM
  #18081  
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Nice file, i liked the 'driving tips' - thanks!

Originally Posted by rccartips
Hi All, Happy New Year.

Haven't touched my minis in a while. I think 1mm ~2mm of droop would be good, to allow the suspension to work.

Attached is my excel file of Mini information. Hope it helps someone.



p.s. Besides car setup, the biggest improvement I got from minis was to learn how to use the brakes.
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Old 01-04-2013, 10:48 AM
  #18082  
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Originally Posted by jjjheimer
Do you use anything special to prevent side to side motion with the rear sway bar? I find there's quite a bit of slop on both the m03/m05.
No. There is a lot of "slop" when the car is sitting on the bench. Dynamically and under load, this may not be duplicated.

Originally Posted by Butler205
Ok, fair enough. My thinking was that when you are trying to get out of a corner, the inside wheel breaks traction. Allowing that wheel to drop down a bit would keep it gripping.
It's okay. That's a common error when transitioning from 4WD to FWD. Front droop does not affect handling much in a Mini. Also, you may have a basic misunderstanding of what droop adjustments are for. If you'll remember, droop adjustments are primarily to influence weight transfer from one end of the car to the other. If you want to transfer weight to one end of the car, you increase the amount of droop on the opposite end of the car. If you want to decrease the amount of weight transfer, you limit or decrease the amount of droop.

So, if you want to keep weight on the front of the car, you decrease the amount of droop so that weight does not transfer to the rear. In a Mini, front droop adjustments don't make much sense. Droop adjustments to the rear are another matter entirely. These can make significant changes in handling.
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Old 01-04-2013, 11:26 AM
  #18083  
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I really have not spent much time working on a setup for my M03, I just happened to stumble across one that works. The biggest thing i found that makes this car carry a crazy amount of corner speed and easy to drive is ride height rake. I'm running about 9mm front ride height and 5mm rear. There are zero droop limiters in the 3Racing shocks i'm using so the car has a huge amount of droop front and back. I haven't measured it but i would probably guess the front at 5mm and the rear at 8mm.

I did this to lower the amount of weight transfer to the front, which in most respects would be the same thing as limiting droop in the rear. I guess I was to lazy to take my shocks apart and add spacers. However droop does 2 things; control weight transfer and control roll from side to side. So by leaving all the droop in the rear it's allowing the rear of the car to roll more which may be part of the reason my car carry's so much corner speed.

Others i race with have done the same thing with there M05's and experienced the same effect. So i guess you could go through the pain of setting droop via the shocks or take the easy way out and use ride height rake.

Other items of interest
Front springs - Tamiya short Red
Rear springs - Tamiya short Blue
50wt shock oil front and rear
1 deg front toe out.
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Old 01-04-2013, 12:01 PM
  #18084  
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There are two more things that lowering the front droop in a mini does : One it lowers the CG when cornering hard and two it gives the Car more responsiveness all around... They might not seem much, but they can make a huge difference entering turns without traction rolling and holding the Racing line better from beginning to end.... It will also allow you not to use any brakes entering the corner, leading to the conservation of momentum throughout the race... I actually have to add some throttle trim to my mini m03, so it can keep going faster when I coast in the turns. No more jerkiness, and no need for a spool like diff in front ....
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Old 01-04-2013, 12:03 PM
  #18085  
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More droop is going to keep the front tyres on the ground longer. The unwanted side effect is that more droop is going to generate a lot more cornering traction which (on carpet at least) means traction roll with the narrow Minis. I've always found that the best balance in carpet is minimum droop above zero (0.5mm-1mm shock shaft extension). On tarmac it probably matters less, but more droop will make the car feel slow to respond. I would always build the shocks for the right amount of droop and run the car low, rather than run the car high to limit the droop - a low car is a fast car.
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Old 01-04-2013, 12:14 PM
  #18086  
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By reducing front droop, I mean putting spacers(two to three pistons) under the shock piston until you get 2mm to 3mm above rideheight of droop.... If you take it to extremes, by reducing the droop even more, you will cause the Car to drive as if it had no suspension at all, thereby traction rolling more, and overheating your Tires... Balance is the key here: not too much droop and not too little droop either....
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Old 01-04-2013, 12:26 PM
  #18087  
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Another issue also is the too low rideheights(under 4mm) that some racers seem to prefer. The suspension has no room to absorb any energy, and the Tires absorb it all , leading to even more traction rolling... 4.5mm to 6mm is ideal...
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Old 01-04-2013, 02:41 PM
  #18088  
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From reading some of your posts, there may be some misunderstanding of what droop is. I am not discounting the fact that I may be the one who is in error here.

The term droop from my touring car days what was adjusted with the droop adjustment screws in the suspension arms or the chassis itself. What the screw did was to either limit or allow more downward movement in the suspension. Thus , if you increased the amount of droop, you would allow more weight transfer to occur on corner entry or exit. In a TC, this is adjusted with the droop screws, unfortunately, in a Mini this has to be done with the amount of shock travel.

Now, some people are under the mistaken belief, increasing droop will keep the front wheels on the ground longer to maintain grip. This may be true if you can make your Mini do a wheel stand on acceleration. In a Mini, you do not want a lot of weight transfer from front to rear as you lose grip and steering. You will get some, which is inevitable, but it's best to minimize it. Keeping weight on the front wheels on acceleration is the most important thing.

Chassis rake is an important adjustment, but is secondary to getting the correct amount of droop. It's sorta like steering trim. You can get the car to run straight with trim, but it's probably better to get the linkages right first.
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Old 01-04-2013, 03:12 PM
  #18089  
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There are no misunderstandings of what droop is here. Too many racers only see weight transfer, and don't understand the other aspects of droop. To learn the other aspects, you need to get familiar with the RC Crew Chief software or any other similar software that will explain in further detail what you'll be able to accomplish with droop....
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Old 01-04-2013, 03:16 PM
  #18090  
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Default Weight transfer and spring rates

Granpa, now I get it why you want stiff rear springs and soft front springs.

It is to help maintain load on the Mini drive wheels. thanks DP
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