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hellbelly

Modern Motors?

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I've been looking at modern motors, I've been trying to understand turns etc but just get confused. Can someone explain, I think that lower turns run faster, but what's all this double wound stuff about?

I know that some ESC's have limits, mine accepts anything down to 18 turns.

I'm looking for a reliable motor, cheap!, faster than the sport-tuned, but not so fast that the battery only lasts 5 mins.

Finally, how do you find out how many turns the Tamiya motors are, ones like the sport-tuned, and the dyna run stock series of motors?

Thanks

Pete

Edited by - hellbelly on 25 Sep 2002 21:38:02

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The lower the number of turns, the higher the RPM.

The Reedy MVP Stock motor about $30 is a good bet, with a 2400mAH battery, you can run a buggy for about 10-15 minutes. My tuned MVP runs about 5 minutes with a 1500mAH on a Blazing Star on asphalt. Today's stock motors run almost like modifieds. The Blazing Star runs real good (good speed and torque) on a 19 turn double modified using 20-tooth pinion. For cheap modifieds, try Trinity Speed Gems. BThe stock class belongs to the MVP.

The choice of motors (turns and winds) depends on what type of car you are running --- buggy, touring, truck? On a toruing car I go as low as 8 turns, but only down to 101-2 turns on a buggy.

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I think the double, triple, quad etc are the power curve of the motor. The higher the number, the smoother the feel, the lower they are the more punchy. I believe this does not change the RPM. Standard tamiya motors are 27 turns. I think the sport motors you said just have more timing to increase torque and RPM, they are still 27 turn.

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Thanks guys. I'm running a Mini, I want higher top speed, and nice smooth running.

With the sport-tuned, it already accelerates incredibly fast, too fast infact, I've adjusted my ESC to have the slowest acceleration and it's still mad.

Pete

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torque = acceleration

--------------------------------------------------------------------------------------

selling one must mean i get two more...right?

I always have one too many when i figure i always need one more.

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Also low turns mean higher currents (battery consumption) and less torque.

Doulbe, triple, quad mean how many parallel wires are used for the windings, in the few windings motors, because of the high currents you need very thick wires, instead they are using 2,3 or 4 thinner in parallel as they are easier to wind and take less place.

Timing increases RPM (am not sure about torque) but also burns the brushes and communator faster.

Cheers

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http://www.vintagetamiyarc.com/

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Here are a few basics - again they are BASICS - hopefully to give more of an idea of what terms mean - as opposed to more technical issues!!:

a) The lower the number of turns - the more "torque" or acceleration the motor theoretically has.....also as a general rule of thumb the max RPM is also very high with a low turn motor. These motors drain the battery pretty quickly - and generally do not have a long life between rebuilds.

B) The number of "winds" can best be described this way - if you have a "single" - the motor will have heaps of torque and be quite savage in accelaration. On the other end of the scale - if you have a quin / quad wind - the accelaration is nowhere near as savage - the motor feels "smoother" - and generally also winds out to a higher top speed.

c) Advancing the timing on a motor usually decreases the torque - and increases the RPM - by changing the angle at which the brushes make contact with the commutator. Advancing a motor is fine - however it will accelerate wear on both brushes and commutator......

For the Mini class of car - something like the sport tuned is fine - as most other things will just have you wheelspinning like mad !!

If you must have more speed - something like a 18 or 20 quad would be a good start......will be VERY fast - but will also be reasonably controllable.

Please feel free to ask questions - as there are a number of us here who can help you.

Cheers

Darryn

Visit my Web Page !!

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Thanks everyone. It is now a lot, lot clearer.

I think I'm going to borrow some motors and try them out in a mini now and see how it handles.

Ta

Pete

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I know a truck puller motor which has 80 turns, very slow but incredible torque... I also know low turn motors with big torque, now is there a dependence of torque to windings and if yes which?

Theoretically torque is proportional to magnetic force, which is proportional to the current, which increases with less turns, like Darryn sais, but why then does the truck motor have 80 turns? Am confused now...

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http://www.vintagetamiyarc.com/

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quote:

I know a truck puller motor which has 80 turns, very slow but incredible torque... I also know low turn motors with big torque, now is there a dependence of torque to windings and if yes which?

id=quote>id=quote>

Is that 80-turn motor of 540/05 size, Theo?

quote:

Theoretically torque is proportional to magnetic force, which is proportional to the current, which increases with less turns, like Darryn sais, but why then does the truck motor have 80 turns? Am confused now...

id=quote>id=quote>

That is all true... for a single conductor in a magnetic field.

Extra turns means the conductor goes through the field again, thus increasing the number conductorsforce pushing on the rotor (which gives you your torque).

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Hi Pete,

I see nobody has yet mentioned that Motors are not the only thing that effects your acceleration ,speed & runtimes.

What size pinion have you got? can you go up to a higher tooth?

Have you ballraced your gearbox and wheels?

What batteries are you using?

All these things have an effect.

I would definantly ballrace if you haven't allready (a must on all cars) and get hold of some 2400 Mah (miliamp) batteries. aswell as a larger pinion. Do this before you buy a new motor as you will probably get your desired effect.

If you can afford it get some 3000 Mah batteries (excellent runtimes) but check first that your charger will charge them as they are a different type of battery.

Cheers

Michael

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Ballraces are a must - they're so cheap these days there's no excuse. Even shelf-queens deserve full BBs.

Capacity of battery only affects run-time; a 3000mAh doesn't go any faster than a 1200mAh.

Gearing makes a difference (although some old Tamiyas haven't got much gearing freedom) and the stock 540 can be geared pretty sky-high for good top speed. Just getting there takes a while...

Mod motors generally should be geared lower. They make their power from high RPMs so they should be allowed to rev & not be overburdened, otherwise they will overheat.

Higher gearing makes the motor work harder, thus draw more amps - meaning less run time.

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I have completely ball-raced it, gearbox and wheels. I currently have a 1700ma battery and that lasts long enough with my sport-tuned motor, I would up it if I needed later on.

Pinion gears, my mini accepts 16, 18 and 20, when I've been reading about motors a lot of them say you need to drop by 2 or 4 teeth when lowering the amount of turns. With my sport-tuned motor I am running a 18t gear.

Cheers

Pete

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Hi hellbelly,

Try Going up to a 20 pinion ,then you should see the extra speed you are looking for, I used to have a sport tuned in mine and a 20 pinion and had no troubles at all.

Pandabear as for batteries not making a difference to speed and only runtimes, HUH~! Mine seem too., i have found that my 1200, 1400, 1500, 1700's all have no where near the punch i get out of my 2400's and even 2000's on a run, or go as fast, But Your saying this doesn't make a difference though?

I'm intrigued.logo_member2.gif

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quote:

Pandabear as for batteries not making a difference to speed and only runtimes, HUH~! Mine seem too., i have found that my 1200, 1400, 1500, 1700's all have no where near the punch i get out of my 2400's and even 2000's on a run, or go as fast, But Your saying this doesn't make a difference though?

I'm intrigued.
icon_smile.gif

id=quote>id=quote>

"Punch" isn't recordable on any scientific statistical device, sorry! icon_smile_big.gif

Seriously speaking, imho its just all driver's feeling. Its a lot like nitro racing... sometimes my old Serpent could get t-boned and part of the muffler might fall off, I'd have a lot less 'punch' thereafter with a detuned pipe - yet my laptimes often improve!

But yeah, admit there are "HV" batteries now available... sure, an extra 0.05V per cell would give you 0.3V extra so the car would theoretically go marginally faster.

quote:

Although the longer the runtime the more you can upgear , which does end up giving you more speed . So they do , don't they?

id=quote>id=quote>

Ya, but its back to the "all other things remaining the same" rule. If you've also changed the gearing, you cannot directly attribute the speed/laptime improvement to your *battery*.

quote:

Maybe it's just my other batteries are sh**.

id=quote>id=quote>

Heh heh... we're still using blackpack 1200s even...

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quote:

Pinion gears, my mini accepts 16, 18 and 20, when I've been reading about motors a lot of them say you need to drop by 2 or 4 teeth when lowering the amount of turns. With my sport-tuned motor I am running a 18t gear.

id=quote>id=quote>

Pete:- the SportTuned is still only a hotter 540, so it will tolerate sky-high gearing. Don't worry too much about overgearing it.

SportTuned in M03 is how we run Mini-class here in Oz. Ppl run 20T pinions as we race on a huge/long track; if your local track is small and tight, the lower gearing of an 18T may give you more acceleration put of corners and improve your laptimes - Try it & see.

SportTuned + 20T on M03 gives us about 9-10mins run time on a 1500 pack, so battery life is not an issue as we race 5mins. Heck, we still use 1200s sometimes... and the ******s running 2/3000s don't even bother recharging between heats.

Top speed is "pretty decent" and Mini Racing is all about good drivers duelling in equal cars anyway. Set it up well and your M03 will turn on a dime without tipping over.

imho the SportTuned works better in M03 than that green "Mini" motor Tamiya used to sell; cheaper too. Any hotter mods is just a waste, all the power disappears in wheelspin.

And for all who haven't seen them before, here's ours:- m03minis.jpg

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quote:

But yeah, admit there are "HV" batteries now available... sure, an extra 0.05V per cell would give you 0.3V extra so the car would theoretically go marginally faster.

id=quote>id=quote>

Hee Hee, i don't even know why i'm right when i am! Cheers i do now!icon_smile_tongue.gif

quote:

Ya, but its back to the "all other things remaining the same" rule. If you've also changed the gearing, you cannot directly attribute the speed/laptime improvement to your *battery*.

id=quote>id=quote>

Ok not directly, just indirectly then icon_smile_wink.gificon_smile_big.gif

Like your mini's, they look cool,icon_smile_cool.gif the bumpers look a bit funny though, but atleast it protects your shell's.

Maybe if i had a bumper / bull baricon_smile_wink.gif my cadburies boost shell would still be with us today!icon_smile_sad.gif

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quote:

Like your mini's, they look cool,
icon_smile_cool.gif
the bumpers look a bit funny though, but atleast it protects your shell's.

Maybe if i had a bumper / bull bar
icon_smile_wink.gif
my cadburies boost shell would still be with us today!

id=quote>id=quote>

That's why I take pix *before* I run the cars... they sure don't look that new & shiny now. icon_smile_big.gif I had to have 2, to allow back-to-back testing. How else would you know which options work, and which don't?

Club rules also used to say "Tamiya parts only". Welll... those bumpers are genuine 100% Tamiya!!

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I thought the original question was regarding motors.......nothing was mentioned about gearing, batteries etc etc.

There are just so many variables in these little ******s - it really is hard to quantify things in general terms......most of the ideas here are spot on though.

Have to disagree on the batteries though - there are many differences in punch and performance - even if you go "WAY BACK" to the early 1200's of the 80's - the SC cells had HEAPS of puch compared to the SCF's - which were more of a duration cell - then we had the SCE cells - which had less punch - but were pretty damned smooth and gave very consitent punch (less than SC's) over the race length - they also like the modified motors better.

Also if you compare the panasonic stock metal hydrides with the Sanyo's - the Panasonics have quite a deal more punch.......internal construction makes alot of difference with these cells.

As for gearing in a mini - you want to run the biggest pinion (unmodified - this is a 20 ) - as not only does it give you more top speed - it reduces the wheelspin - this is the biggest "enemy" in racing the mini competitively.

On the battery front front again - you can also change the way a battery perfoms - by using different methods to charge it.......there are so many tricks .............

Cheers guys

Darryn

Visit my Web Page !!

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Thanks guys, i played around today and put a 20t gear on my sport-tuned, and it does seem faster.

I tried a 19 turn double, should I lower the gear to 18t for this one if I plan to use it?

And now I think I'm going to try some different batteries!!

Pete

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quote:

On the battery front front again - you can also change the way a battery perfoms - by using different methods to charge it.......there are so many tricks .............

id=quote>id=quote>

Will cede the racing tips to you Darryn, for you would sure know all the racing tricks in the biz icon_smile_evil.gif. Although I swear at one stage (early-mid 90s) everyone was busy spark/shorting their batteries right at the startline... crazy ******s!

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