AdrianM

iTrader: (4)

Come to think about why not just get rid of the damn batt limit on mah and just limit to any sub c I mean we are coming off the track with excess runtime so at this time do we really need to limit mah's.
That will help control the battery wars for capacity and just deal with the voltages, which the equipment can be designed around that problem.

In the last year we have seen 3 increases in capacity, and 2 increases in voltage just for IB cells. New cells have been introduced from IB, GP, IP and East Power during the same time. If there were no battery rules everytime a new cell popped up everyone would have to run out and get them. Regulated annual battery approvals reduce cost to racers

One thing that should really be looked at is start looking for different materials for the motors so they can handle the heat.

Thats being looked at now but Neo mags in brushed motors and Sintered Neo rotors in BL only temporaily fix the problem. In a year we will have even better batts and we will be back to melting, shutting down and blowing stuff up. We need a big step towards resolving our problems....less voltage.

Maybe the motor manufactures can come up with a self regulating device within the motor that wont allow the ampdraw to go over a set limit. Come up with something that all will agree as the standerd.

I have talked with a few companies about this. The circuit needed is not simple and you need large heat sinks to dissipate the energy not sent to the motor. A device like this is possible but it would be large, possibly inconsistant in its limiting due to component tolerances and heat, difficult to tech for accuracy, impossible to fit on to current chassis, you get the point. This is most likely not the way to go.

habicht

It's no problem to produce a brushless speed controller and motor, that does not brake. It's also no problem to reduce the power, so that it has a good life time. In this case it will not be fast enough to get world champion or it will be very expensive with the rules we have now, to make it last longer.

So if you don't want to reduce speed, there is only one way to handle the speed with an acceptable price:

Foam tyres and sintered neodym magnets.

The question is: How many of you did already try the Intellect 4200 SHV cells.
A 3.5T brushless do have 600 to 1000W of max. power, depending on the battery quality. The voltage of SHV cells is over 6.4volt at 100A.
5 of them have the same power as 6 cells normal Intellect 4200.
So does it really matter to reduce the number of cells?
4 cells will even have the same speed as GP3300 two years ago with a 150g lighter car.
So what is so bad on the 4 cell idea?

I think 2WD with rubber tyres are no fun at all. In this case only PRO10 will make fun with this amount of power.

At this time we have the power of a 1/10 gas car but we don't have the same tyres. The rubber tyres did not improve the last 5 years.

speedxl

Adrian that would be the case if we were looking at 1200 mah packs against 4200 mah. Plus the race times hasnt been changed, its still 5 min for 10th scale and eight for 12scale. We are coming off the track with excessive runtime. So at this time do we really have a problem with mah numbers no!! because we can only use so much. It wont make a difference if you showed up with 8000 mah batteries to race, you'll only use so much in a 5 minute touring mod race . The problem is controlling the voltage to the motor. At this point anything higher then 1.21 volts is over kill!

TC Guy

I have to go with Adrian on this one. The shear amount of money I've spent in batteries over the course of the last year since I've gotten back into this hobby is insane. Not to mention the number of capacity increases in the last several months. Not all of us are fully sponsored by a battery matcher/company and get the newest, hottest cells sent to us everytime we're about to travel to a race. I'm not suggesting we shouldn't embrace the arrival of new technologies, but (maybe) there should be some form of guidence (I don't want to say restriction, trying to be PC).

tonyv

iTrader: (1)

Ok, got it. Glad we agree . Maybe I'll learn how to read now

I also agree with Josh's post. I think it covers most of the problems that we (will soon) face.

Some have argued that things will continue to develop and that even if we make changes like reducing the cell count we will have similar discussions a few years later. I fully agree. But contrary to using that as an argument to not bother I see that as the best argument to make changes now eventhough the problems don't seem to be having a direct effect on the number of people driving touring cars at the moment. That effect will come and we need to stay ahead of it. When the time comes in a couple of years time that some of the problems that are being discussed here surface again despite rule changes we make now, we have the discussion again and make changes again for the exact same reason.

This discussion is not really about going fast or not going fast. It is also not about wanting to push the limit. This discussion is where we put that limit for the next few years. There will allways be a limit and it is defined by the rules we adopt. Manufacturors will allways try and find ways to get the most out of their products and design the best possible products that the rules allow. That will not change whatever rules we adopt. So I suggest we quit worrying about that part of the discussion.

vtl1180ny

2wd gearbox cars with a slipper clutch would take a lot of strain off the motor and electronics...

Let's face it that anything that benefits people who solely race are the exact opposite of the majority who just bash their cars....

These days, I bash more than I race but since I'm an old fart who's accumulated many cars in my 30 years in this hobby I can afford to have my shelf queen "race" cars and my run in the parking lots "basher" cars....

But I really don't want to have to accumulate any more 4 cell packs. If it comes down to 4 cell TC I'll stop racing TC and only race 12th scale just because I don't feel like having more 4 cell packs than I know what to do with...

I'm just going to sit back and wait for the return of the pan car and GTP bodies.... Everything comes full circle...

tonyv

iTrader: (1)

While I agree with Adrian on the principle I agree with you that it is voltage that is the real reason we buy new packs regularly. Problem there is that while we have set points during the year that new cells are homologated, between these points the homologated cells are improved all the time. An IB4200 bought three months ago simply will have less voltage than one bought today. Same cell according to the rules, nevertheless higher voltage. For the homologation rules to truly have an effect on costs we would need to have a way to tie homologation to voltage (and IR) instead of capacity. Having said that, I see no way to do that realistically which means the current homologation approach is the best we can hope for.

speedxl

Sorry deleted post! I posted twice!

speedxl

Let me try to explain it better. The rules to control batteries capacity were great when it was 4 min racing with 1200 mah batts to keep someone from showing up with say 2000 mah packs. At that point the guy with the larger capacity can pull the trigger harder and win. Now racing is 5 min and we're racing with 3800 mah max capacity and 4200's around the corner! . We are coming off the track with plenty of runtime left. So why limit the mah now! even if you ran a 8000 mah batt you will never use all of it. So just limit the batt to a physical size limit!. Think about it do we really need to control Mah's. If the time limit were raised to 8 min then that changes the situation!!

AdrianM

iTrader: (4)

That's 1/12th scale and it IS coming back. Pro-10 will never come back because there is no need for bigger 1/12th cars.


habicht - Foam tires are the answer huh? I guess thats why all these carpet tracks are buying rubber tires from Take Off all of the sudden. Every day I talk to track owners that are being told by their local racers that they are done with foam tires.

As far as new tires... Take Off and Yokomo have released new tires in the last year and Jaco will have new rubber tires sometime this year

tones

iTrader: (55)

'Foam tyres give more grip and are more lightweight, so it would help.'

imo, foams are harder on motors. sure there is less weight there but the motors rev out higher and you can drive alot more punched.

vtl1180ny

The only thing is LiPo is coing and a single cell LiPo doesn't make the same voltage as a 4 cell NiMh....

Rubber tires just don't give the same grip as foams and for those of us who came from off road to carpet it's hard to get used to having so much traction.

Plus, it's pretty much only the east coast running foam....

Is it me or is this just not fun anymore? DerekB?????

Chris Adams

Well, I have done no testing so this might be a blind shot but 3.5 years ago when I first got into this racing thing, I never herd anything about going too fast or speed controllers frying... That is because they were at a voltage that was less throughout the race. Would it be obsurd to say that if we went to 5 cells today, we would be the same speed we were 3.5 years ago because of the increased voltage and decreased internal resistance?

Jumping from 6 cells to 4 cells in my opinion is a mistake. It simply changes what we all enjoy way too much. Give 5 cells 2-3 years and when this situation re-kindles itself at this time, take the time and decide if 4 cells is appropriate. I understand the argument that going to 4 cells allows us to quickly transition into 1 cell lipo. Do we really want to get rid of half of our voltage so quickly? Small steps keep things around...large scare people off.

A current limiter would be pretty sweet also...AMB makes transponders that almost all serious racers have, why couldn't a company make current limiters much like amb has?

Rick Hohwart

The easiest way to solve the problem is to voluntairly use less powerful motors. It costs NOTHING.

There is no rule that says you have to run a 7-turn touring car motor. We choose to and that choice leads to the problems we face. The same motor set-up (timing, brushes, springs) with a 10 turn armature will eliminate the problem.

If you don't want to blow up your motor or ESC, don't.

MattW

Trouble is, when we ran 12 turn in the UK we could burn motors up. Not speedos maybe. That was on 3300's, so suspect it would be really bad now with IB 4200's