View Full Version : ESC - any good? (GM)

08-21-2003, 12:17 PM
I'm rather new to R/C. At the moment I have a 3 or 4 year old TL01 of Tamiya with standard 540 motor and some standard Mechanical Speed Control.

I would like to buy myself an ESC and have some opportunities.
First one is a GM ASP. I can buy it with more than 50% discount and it looks pretty good, but I'm new to this ESC thing, so I want anyone's opinion about this thing. Specs are at (in english)

Another one which will require me to pay more money is a T2M No Limit. Does anyone know anything about that one?

Is GM any good and would it be a good ESC to drive with the next 1, 2 or 3 years? Will it work ok with the standard 540 motor? But will it work as good or even better with a 19T stock motor (hand-out at dutch national championship races)? I will probably buy myself another (better) (stock) motor in the near future.

08-21-2003, 01:25 PM
I have & use a GM speedo (V4). I must say that they have some really good stuff. If you can get a GM ASP at the price you mentioned,then by all means-get it! It should be all you need for the next 2-3 years. Another one to look into (seeing that you're in Europe) would be the LRP line of speedos,such as the Quantum line. But at least,get rid of the mechanical speedo!

08-21-2003, 01:32 PM
Thanks for the quick reply. (More replies are welcome of course! :)

One thing to mention: the GM ASP weighs in at 64grams.

I know I have to get rid of the mechanical speedo, but I still want to keep it, because at the moment the only cup I could enter in with a competitive car is the Tamiya Euro Cup Stock touring car class. That means using an Mechanical speedo.

After some time if I like racing competitive I need to buy myself a nice 'pro' chassis.

Also, when I want to drive competitively (not internation, just local and maybe national sub top) do I really need to have these matched cells (or equipment for it) and use good dischargers and stuff? I use just one car bulb to get the final power out of the stick and then recharge them with a simple peak detector charger (3A). I have Sanyo RC2400 sticks.

08-21-2003, 01:33 PM
Im with Irvan.....i run oval and i love my V4......all Gm speedos are very smal and lightweight.....could they be another option instead of a quantum, no doubt about it!

08-21-2003, 02:36 PM
I must agree with the above. I have two GM4R and a GMV12 on the way. The two 4R's are mounted in both of my legands cars and run a street spec motor(i think it's 21turn)and i run 4 cell batteries. I've had these two ESC for 1 1/2 years with no problems. I would recomend to use the GM racing product line to anyone.

08-21-2003, 03:50 PM
But what about the 64g weight?

And what do you think of the ASP (Active Steering & Power control) function?

08-22-2003, 08:53 AM
FixxIt: I will look into its specs and get back to you....but to be competitive on a semi-national level means matched batteries. People could blame a lost race on the .003 difference in their dont need them for club level. as for the equipment, it would be much cheaper to buy matched than buy a brick of cels and trying to get the even ones. Matched cells used to be about equalizing the cells, now many matched packs come with over the top voltage with out the over the top price. For discharging, pick up a trinity real time 2 discharger or somthing like it. Bring the cells down individually. if you have to run stick packs for that class then dont wory about it. As for chargers/dischargers here are a few that are not $400....LOL...the duratrax digital parahinna charger has a adjustable peak meaning you can get rid of false peaks and charge 4 and 6 cell packs to their best.....the novak millenium pro and the CE pitbull are both great chargers, but you would want a discharger also....i think it is integy that makes the Reactor series of dischargers..........what charger do you have now? Hope this helps

08-22-2003, 11:21 AM
Also, when I want to drive competitively (not internation, just local and maybe national sub top) do I really need to have these matched cells (or equipment for it) and use good dischargers and stuff? I use just one car bulb to get the final power out of the stick and then recharge them with a simple peak detector charger (3A). I have Sanyo RC2400 sticks.

first i would get a charger that charges more than 3amps,, get you a good charger like the new lrp or the competion electronics pitbull both with peak detects and will help you in the future when you go to NIMH batteries. Right now your running 2400s that is NICD batteries in a stick form,, if so make you a simple discharger that brings the packs down at the amp you are racing at out of a series of car light bulbs. one equal 2 amp {1157s} so ten will make a 20amp dumper, but if you go racing more compitively you will get packs that are matched and side by side then you can use a charger {ex. T35 ,GFX, or Homemade dumpster until lights go out } to bring cells down to .09 and then place on a equalizing tray and bring on down each cell,, and dead short if you perfer { which i do }. as for speedos George is right,, and i also race with George on several ocassions. hope this helps :thumbsup: .

BigDon :cool:

08-22-2003, 11:43 AM
Main things to look for in a charger:
1-Variable peak detect from .03mv to .07mv
2-Vari charge rate from an amp tp 6 or 7
3- 4-6 cell ( You never know when you'll need a 4 cell pack if you run 6 cell: Comm lathe???)
4- NiMH compatibility

Bigdon is right about the bulbs, they work fine, but watch them as they go out, dont leave them on too still looking at the gm speedo you mentioned, get back to you soon on it

08-22-2003, 12:19 PM
also, they are cut off boxes that you solder into homemade dumpster that stop the discharge once the packs reach 5.4 volts which is good for someone running six cell packs,which you are if you are racing touring cars,, if that is the way you decide to go. that way you can hook them up and not have to baby set your packs while they discharge them ,, you can be doing other things,,, working on setup on the car, working on a motor, running the next heat , running in the amain,, or taking pictures with the hooters girl which is very blessed after winning the main :eek: .. ok,ok, ok i got carried away just alittle bit,, but you get the picture :lol: .


08-22-2003, 04:48 PM
You guys are really helping me with this. Thanks!

Some more questions:
1-Variable peak detect from .03mv to .07mv
what is mv?
2-Vari charge rate from an amp tp 6 or 7
what is amp tp? I guess this just means I need at least a 6 or 7 amp charger, huh?
I guess it's best for me to buy a charger with discharging abilities. Do I really make my batteries bad when I just use one car bulb for discharging? Maybe it's even better not to discharge at all then?
duratrax digital parahinna will be best for me then? I don't have the money to buy it yet though. Will any charger/discharger with the specs mentioned by speadfreak be ok, no matter the manufacturer?

I really don't know much about electrics, so I don't know what to do with things like 'bring cells down to .09 and then place on a equalizing tray and bring on down each cell' or is that for matching yourself?
What about 'adjustable peak meaning you can get rid of false peaks'?

Man, I must sound dumb here! :confused:

I see that I won't be racing competitively soon. I need to learn a lot more than I know right now. First I need to run for fun and maybe at club level. Although a good charger/discharger is needed I see.

Btw. I already ordered the GM ASP, so I hope your verdict will be good! :)

08-22-2003, 05:21 PM
mV stands for millivolt. I don't know what tp stands for, though!

Adjustable peak detect: When you charge cells, voltage raise up to a certain point and then drops back. The peak detecting sensor in a charger will monitor for that drop and stop charging. So, when the voltage starts dropping, your batteries are almost full charged. The amount of voltage drop you want is what you want to be able to adjust depending on the type of cells and the number of cells. NiCads were charged until voltage had dropped by 15mV per cell (thus 60 mV for a 4 cell pack) while NiMh are charged until the drop is 8-12 mV per cell (30-50 mV for a 4 cell pack)

As for discharging, common wisdom is that you should discharge your batteries to a rate that is as close as possible to what you are discharging them on the track. Leaving a charge in NiCads is bad since these batteries tend to developp a memory and at some point, they will not perform well because they will get "lazy". For NiMh, it is said that they don't have a memory but I can't confirm because I've never tried to leave a charge in them...

If cost is an issue, as it was said previously, you might not need a sophisticated discharger. 10 car lightbulbs wired in parallel and a voltmeter will suffice. You will have to monitor the discharge and be sure that you stop at 3.6V for 4 cells and 5.4V for 6 cells. And to do that, you don't need an expensive voltmeter. I don't know what you can find in Netherlands but here in Canada you can find a few models that would be suitable for 25-30$. I'd be very surprised if you couldn't find some equivalent near you.

When you discharge, you want to bring the average voltage of each cell to 0.9V. That is how you know they are almost completely discharged. But this is an average because each cell, no matter how good is the match, will be at a sightly different voltage, and if you continue to discharge the cells as a pack passed that 0.9V limit, you might come to a point where some cells are completely dead while others are not and this will damage your pack. Thus, you want to continue to discharge each cell individually and that is what a tray is for. Once every cell is down to 0, then you might want to dead-short your pack by running a wire between the positive and negative poles of your battery. This helps to maintain the voltage as high as possible.

But, those last 2 step is optionnal and you might not want to bother with them unless getting every drop of possible performance is crucial... You will gain much more by spending time on the track that fiddling with your batteries. Just make sure that you discharge your batteries to 0.9V per cell and that is usually enough.

A last bit of advice, get the best charger you can afford. A good quality charger will last for years and will help to maintain your batteries in good shape.

I hope this helps,

Martin Paradis

08-22-2003, 07:58 PM
Dont worry about sounding dumb, we all started somewhere.....its better you ask about this stuff then it go unknown.......the amp tp was ment to say TO, not TP, sorry about that. I would save up for a set of discharge bulbs, an auto cut off device for them, and that duratrax charger. It has a variable peak and charge rate, and can also charge one cell ( i believe) which you can do a glow starter cell for nitro it can charge NIMH and NICAD pretty well. I know racers that are competitive with them in 4 cell oval, so they cant be bad at all. they run about 55 bucks, and its ac/dc, so its a good charger for the price. I may buy one as a backup for my T35 Stealth, either that or a Pitbull or a Pulsar, but this is the cheapest by far!

08-23-2003, 06:42 AM
The Piranha Digital Peak charger is a 110VAC (and 12V DC) charger. Here in the Netherlands we use 220V or 230V with other plugs...
I also saw that this charger only charges at 3A max with AC, which is enough for now, but not when I change to (3300) NiMH right?

As for discharging, I think it's easier for me to have discharger or even better a charger with discharging capabilities.

When looking in LHS I should probably stick to the 4 tips speedfreak gave me right?
1-Variable peak detect from .03mv to .07mv
2-Vari charge rate from an amp to 6 or 7 (Isn't 5 enough?)
3- 4-6 cell
4- NiMH compatibility

08-23-2003, 07:19 AM
I ordered it yesterday and I got it in today! Wooho! :thumbsup:

The only thing is that it's probably pretty hard for me to put it in and make it work. I guess I have to solder quite some things and/or get the correct plugs.

If anyone have some help on using the speedo, I would really appreciate it. My motor is a standard Tamiya RS540 thing with Tamiya plugs. The speedo just has some wires with thick metal wire coming out of the end. Do I need to solder it or can I get some plugs and put it on them?
I also need to solder one of the schottky diodes on it right? Is this difficult? I will use the transistor type; do I need to solder it as near as possible to the speedo itself or is anywhere on the wires ok?
And is there a special way to connect one wire to the motor+ AND the battery+?
The plugs for my receiver are in white-red-black color; the wires that came with my radio are yellow-red-black. Do I need the same order, but the white one for the yellow one? I need to change the plug of them too, but those were shipped in the package.

Thanks in advance guys. You're helping me a lot already.

I also need to use a jumper on this thing to program it, but that won't be a problem, because I'm used to jumpers and stuff (computer nerd?? almost! lol ;) )

08-23-2003, 09:09 AM
Fix IT- When you have a three wire speedo you must make a "jumper" wire from the pos lead. You can cut a small bit of the wires shrinkwrap and solder another wire in that spot. This way, you have a wire for the motor + and the battery +. It should look like a "Wire T" when you are done. The main wire being the top and the jumper being the middle.

You can buy plugs for motors and batteries at a lot of places. I would recomend you get rid of the tamiya conectors unless it is a mandatory thing for the class......even though you are using the stock motor now, you can still use these plugs in the future if you install them....Deans plugs seem to be the plug of choice, and the Sermos or Powerpole plugs are in second. Either way, you must still solder to put the jumper wire on and to put the plugs onto that.
Just remember, solder joints are resistance. Do not skimp out on how you solder the jumper or the plugs because it may be somthing that causes hidden problems in the future. Solder the shocktty(or whatever it is) diode where they tell you too, some say on the motor, some say on the speedo. Just cut a smal piece of the wire shrinkwrap away as you will for the jumper wire ands older away....make sure it is the right polarity. People usally use them close to the motor( on the tabs) because it will get rid of interferrence it may create.....
Your conectors are the same except for the white/ yellow difference you say? The white, and the yelow are both the signal wires for your servos/ use the yellow in the same order as your servo plugs.
Have Fun!

08-23-2003, 09:10 AM
I just read where your from! WOW! This board is everywhere! LOL

08-24-2003, 08:03 AM
Thanks. I think I must be able to handle the mounting of the speedo on my car.

For the Tamiyastock cup races I don't know what I may change in the wires. At least I know I need a mechanical speedo and the batteries need to be connected by the tamiya plug. I hope the motor plug can be something different so at least that will be more efficient; then I could have the MSC and the ESC use a better plug (Deans if I'll be able to find one here) to the motor. But I guess I'll use the standard motor plug (also for the ESC) that comes with the RS540 standard tamiya motor, but I need to find the plugs for that too.

By the way, any of you guys looked at the Active Steering and Power control (ASP) of the GM speedo? I think it can be neat, but I don't think it will handle all the oversteering and understeering as much as they say.
Well, thinks like maximum breaking and minimum braking and torque control and traction control are pretty cool features no?

08-24-2003, 08:13 AM
The ASP feature would be great for should do fairly well on any on-road application also.....i nioticed you said you were going to hook up 2 speed controls (ESC/MSC) to one motor? Im pretty sure when they said to have the MSC on it it meant to use it......can anyone help?

08-24-2003, 09:37 AM
I guess you misunderstood or I explained it badly. I meant that for that cup you can only use a MSC (in stock touring cup). So when I will keep my MSC and second servo, so if I want to race in that cup I can change to the MSC.

When racing for fun or so I will use the GM ASP of course, without the MSC. I don't think you can wire two speedos at the same time, right?

I can't wait till tuesday; then I'll be able to solder everything on it and try the GM ASP out!

08-24-2003, 06:40 PM
LOL. sorry, i believe i read it wrong!........i dont think you would be able to have 2 hooked up even if only using one......i would Not recomend trying it.......good luck soldering!

08-27-2003, 07:51 AM
I fitted the GM ASP in the car and it works.
I soldered a wire to make a T-joint and I soldered the Schottky diode on. It's not the best soldering job ever done, but it's good enough.
I left the wires pretty long in case something went wrong and I have some stupid plugs on there for the moment. At this time it's all ok, because the standard RS540 motor isn't one of the fastest to say the least and it won't draw a lot of current.

Thanks for all the info and now I am looking for the next update...

What should I buy first?
Better motor?
New wheels/tires?

08-27-2003, 08:59 AM
If your tires and wheels are dead i would by those use having power when you cant put it on the track! Then i would buy another motor, what are the specs for your class?

08-27-2003, 09:43 AM
I haven't raced on any real track in my life! :(

I was thinking to start in the tamiya stock touring car class if I want to race, but that season is over, so I'd have to wait till somewhere in next year.
For that class, I can only have the motor I have right now and I can only use two sorts of tires (standard slick or radial) and only the tamiya MSC. TL01 chassis and a couple of hop-ups (like ball bearings and oil filled shocks, which I already have). The only problem is that they don't know the specific specs for nest year, because they want to let the RTR (expert built) cars of tamiya run in this stock class as well, but some of these cars are sold with ESC.

The circuit/club nearest by have some evening races during the season. They don't have many specs, but for motor: rebuildable Corally 19 single.

This year's dutch championship specs are: a hand-out 19 turns rebuildable motor (handed out at the start of the season/race for a price of course) and Take Off CS-27 tires and rims. Also only 4-door-sedan bodies.

I think I will only race for fun and maybe in club competitions at most; at least for some time.

So what kind of motor should I buy? I guess some sort of 19t rebuildable, right? Except I don't know anything about rebuilding and cleaning a motor, but I guess I have to learn that too.

That way I can use the RS540 motor with my MSC and store it for when I need them and use the new motor with the ESC as standard; then I can solder good plugs on them too. Only the batteries will remain with (gold) tamiya plugs for a while then.

What kind of tires and rims and inserts should I get? First I will probably use them at parking lots and stuff, but they need to do good on good tracks as well.

08-27-2003, 09:42 PM
I dont have a clue on touring tires, im an oval guy myself, but i can help with a motor. A 19t will be faster, but may reqiure a little more matenience......tuning a motor for bashing is as follows:
oil it every run or two, dont kill the bushings/bearings
clean the comm and brushes with a comm stick ( or a Pink Pearl eraser, that brand works great for me, a pencil eraser is about the size of a comm, so the brishes are a snap)
replace brushes whenever your car feels real slow.....for bashing, i usally do it when it doesnt jump as far (offroad) or whenever i can get them.
Shoot the motor with motor spray every 3 or 4 runs just to get the crap out.........a 19t should be plenty fast for just having fun, and you may be able to use the same one in competition too...remember, gearing can play a big part in how the car feels!

08-28-2003, 10:54 AM
Thanks again for the info. What is that bashing you keep mentioning?

Do I need any special oil?
And what is that motor spray? How expensive is it?

For the cleaning of comm and brushes I can just use a good pencil eraser?

08-29-2003, 09:54 AM
When i refer to "bashing" its just messing around in your yard or in a parking real racing.....motor oil is specific to type of motor: bushings have a different oil than those motors that use bearings. Trinity makes a few different kinds, so does bolink anda few other you know anyone that races rc cars at a track? A pencil eraser will work fine for a while but when the comm begine to wear away the only thing you can do is cut it. Someone who races may have a comm lathe and could spin your armature up for free, or a small fee if they need cash........this will showthe greatest performance gain is a beaten motor

08-29-2003, 04:43 PM
I went to the LHS and the guy 'gave' me a cheap 11x2 panther motor from Peak. I guess it will do for me and it wasn't expensive and will bring me a lot of speed. :)
He advised me to just stay running the 19t pinion, although maybe for some tracks I need a 21 or 23; those are the only three options on this chassis.
He isn't the best advisor; nowhere near as good as what you tell me, but from some point of view he is a VERY good advisor (he's funny and friendly and sells his products very well! ;))
I bought some gold plugs with it (got them for free when I asked for it) and I got some motor spray and some oil for all gears, bushings and bearings (plastic and metal).
This should keep me busy for a while, because I have promised myself not to buy anything for the car for at least a month! This hobby is draining money like... like... oh well I can't find something similar :p

Next thing on the list are rims and tires though. On road they are almost as slicks in a mud pool! heheh.

08-29-2003, 06:40 PM
You think thats a lot of spending money? Im about to drop out like $350 for pan car glad there is a high resale in the stuff i m buying! If the GM can handle that motor, yo should have fun...theres no more fun that messing around with a fast car........Im sure that if that guy spent a day or two on the internet he could be a better salesman.......some guys at your LHS's are just there for a job and dont know what a mod motor is, some have been racingfor years and can tell you all there is to know.....personally, i have been racing for 3 years and have gained an emmense amount of knowlege.......i have trouble aplying it to what i do because i always get caught up in long as the guys that sell you stuff arnt A** holes, they are good to sounds like hes a nice guy, so let us know how everything turns out!

08-29-2003, 09:56 PM
Yeah, let's not get started on spending money! :)

If you need any help on tires, I'd like to offer my opinions. CS-27's are very good handouts...but it greatly depends on track temperatures and what surface.

Sounds like you are going on the right track, though!

08-30-2003, 03:09 PM
Ok ok, I'm not spending huge amounts of money, but I have never even raced on a track before, so I don't even know how that is and if I'm going to continue in that direction.
What's more, I don't have that much money. I didn't have a job, but I start a new one on monday as a programmer, so money should come back, but I have to save a lot for other things as well.

For the tires, I just need some good basic allround tires. I need new rims for them too and if necessary I need inserts also. I don't want to spend much for them, because when I do get started with racing, those tires will already be down to the rims I guess! lol So this is just as a start. I don't want to spend much, so let's say $40 at most, which isn't much I know.

One more thing: I won't buy anything for the car for at least a month, so the suggestions you guys make, won't be changed into any real buys just yet.

I will keep checking this forum of course and keep you updated on my car and stuff.

08-30-2003, 05:46 PM
I would ask the touring section about some tire suggestions.......but Xray seems to be pointing you well......

08-31-2003, 03:42 PM
I tried my new motor in an almost open space here on pretty nice tarmac (I think it's called tarmac in english). Finally I was able to press the 'pedal to the metal'...

It went sooo incredibly fast for me. Much faster than I was used too. My standard tamiya tl01-kit tires are really not very good (any more). At full speed I loose control. Probablt by running over some minor bumbs or something. Whne steering just a little it was ok.

But I made a stupid crash. The car was stuck half underneath some box with plants in it. I got it out, but the top of the ESC was off... And it didn't run anymore. :(

It seems to be that one of the wires in the plug to the battery is not very good, because by pushing/pulling it some way near the plug, it seems to work. I had the glitches before (after installing the new motor, when breaking it in in the car), but it suddenly was fixed. It was probably the same problem. I am pretty sure the ESC is not broken; maybe the wire is broken somewhere else (near the ESC maybe or at the ESC), but it seems ok. I think (and hope) I'm right! :)

I am very happy with the speed though. It's incredible (and not even near the speed you guys are running on). I really want to show it to the guy where I soldered everything (brother of my girlfriend), bu I won't see him until friday!

08-31-2003, 11:04 PM
MRfixit 1 thing to check from your last post is the solder joints. You said earlier that they were not great but would work. My opinion is that 1 of the joints is loose. I have had some good crashes and pulled those connections apart. If you are running out on the tarmac I would take out all of the brearings and clean them. Spraying out with your motor cleaner. and appying new oil they will get very dirty and start to bind up. I don't remember if anyone awnsered your question about a charger but here is my opinion since you live abroad how about a DC charger ( little more money) and power supply that converts the 220 AC. Just a thought. Hope this helps. Check with your local race tracks and see if you can paractice on a non race day. Thats how I started 20 some years ago
Good luck
Dan :wave:

09-01-2003, 09:56 AM
Mini hit it on the spot......if you want to get into racing but arnt sure if you will like it, just practice on non race days........did your speedo case crack at all when you wrecked? That should be the worst of your problems.....just check the solder joints.....

09-01-2003, 01:40 PM
The case didn't actually crack; just the top (with all electrics and wires) came off. I am fairly sure it should be able to do that, because it 'clicks' into place and this way you're able to change the wires on the speedo.

The solder joints are still in tact. I think the problem is the non-soldered tamiya plug that goes to the battery.

When I'm going for a new charger I will look into a DC charger and get a seperate power supply for it. Do I need any special power supply? Maybe I need to look for the current it gives or something? I'm no electrics guy, so....

09-01-2003, 01:50 PM
I would look for a power supply that has 15 amps capacity......that should be enought o charge a battery aand run the charger.....or even less depending what charger you are buying....i know the novak ones draw like 2.5 amps while charging, so maybe a 10 amp model would suit needs to have 220Volts in and 12-14 volts DC out......the current it provides denotes how fast you can charge, you want to charge at anywhere from 4 to 7 amps.....dont go any higher for messing around........

09-01-2003, 11:56 PM
mrfixxit do not go any lower than a ten amp power supply. the reason is if you want to get into any type of racing there will come a time when you want to charge more than 1 battery at a time. you can run 2 chargers at 5 amps and be ok. with the power supply try to get the biggest one you can afford. But stay away from the 3-5 amp ones that are out there. :thumbsup:

Dave how are my pinions and spurs treating you? :wave:

09-02-2003, 10:58 AM
I love em! Great buy! It was a help to me and my car.....having 4 pinions meant either i run good, or i run overgeared...thanks !LOL

08-04-2005, 09:52 AM
where can I get them?

08-04-2005, 09:56 AM
Wow, 2 years old and I still get an email notification for this bought mine through Tonys Hobbies in New York, but I know Horizon Hobby also sells GM stuff (Last I knew, I havent races in close to a year now).