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Discussion Starter · #1 ·
when i get this ESC...what is the max speed i can do? ESC is 13T limit...
 

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migoreng said:
when i get this ESC...what is the max speed i can do? ESC is 13T limit...

That's a "how long is my piece of string" question, imho.



All depends on:


-what motor you're using, what RPM does it do?


-what gearing you're using?


-how big are your tyres?


-what kind of ground are you running on?


-bearings? don't forget bearings
 

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Discussion Starter · #3 ·
i got my bearings already..


i want the fastest top speedpossible using what is currently sold
 

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Hard to tell... as a ROUGH GUESSTIMATE...



A decent 13/14T motor probably does about 32,000-35,000 rpm.


Your tyres are ~65mm.


Gear ratio... probably around 7:1 at a rough guess.


So:


35,000 / 7 (how many times your wheels turn per minute)


x 60 min


x 65mm x pi 3.142 (the distance each wheel turn travels)


= 61269 m / hr


= 61 km/h





Betcha thinking - Should have paid more attention at math class, eh??









btw... ESC don't make your car go "faster". If you connect your battery *direct* to your motor then that's the same top speed as any ESC or MSC can create... you're still only running from the same 7.2V from the same battery.


ESC only gives you better control (no steps) over your speed, and it is more efficient (no power wasted on resistor).
 

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Discussion Starter · #5 ·
ahhh...thanks for that..


only 61kph



hmm
 

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haha... trust me... if you show ANY of your mates any RC car doing a *true* 60 km/h they'll all say its doing 100+. Its small size makes it look a lot faster and the shopkeep will say that's a "scale speed" of 600 (=60X 10th)... yeah, if you believe salesmen.



And do remember... if you HIT anything hard at that crazy speed... your car will be in 101 pieces before any of it comes to a standstill.


(I did that once straight into a stone kerb... the car bounced back 10+ feet before it landed!!
The xtal from the RX flew out 20 feet ahead!!!
)





ps: If you don't want to find out how fast your car really runs, don't go and buy a radar gun or a handheld GPS unit, okie??
 

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Yeah, an unavoidable incidentinvolving a loose RX batteryconnection... right when the engine (nitro) was running at full wide open throttle. It was heading towards a very busy main road too @ peak hour
so it was "lucky" that it hit a bump and veered into the centre kerb instead.


(No, failsafes don't work without battery either.
)
 

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THROTTLE RETURN SPRING


Regards,


AUSRC
 

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lol. i put a 10 turn i got from a fella at work in ma tl01 wit speed tuned gears, bb's, etc that speed stuff, melted part of the chassis the tl-01 doesnt get enough cooling although i did have a standard prop shaft and gerar diffs, but it was funny
 

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PeeDee said:
lol. i put a 10 turn i got from a fella at work in ma tl01 wit speed tuned gears, bb's, etc that speed stuff, melted part of the chassis the tl-01 doesnt get enough cooling although i did have a standard prop shaft and gerar diffs, but it was funny

Low-turn motors must be geared lower than stock, as they make their power from high revs not stump-pulling. Mod motors have less torque than high-turn motors.


High gearing needs torque to work; SpeedTuned gears give the TL01 super-high gearing.
 

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Discussion Starter · #15 ·
i've got my speed tuned gear and pinion..


what kind of motor you talking about that i need?


confused about what you saying above


i see specs on motors about 4, quad or something...which ones arebest for $40


saw a fireball 17T (15T ran out at hobbyco) today and i think the brand was venom...how goodis that?
 
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PeeDee wrote:



<table width="100%" border="0" cellpadding="1" cellspacing="0" bgcolor="#494949">

<t><tr>
<td><table width="100%" border="0" cellpadding="2" cellspacing="0" bgcolor="#ffffff">
<t><tr>
<td class="text">lol.
i put a 10 turn i got from a fella at work in ma tl01 wit speed tuned
gears, bb's, etc that speed stuff, melted part of the chassis the tl-01
doesnt get enough cooling although i did have a standard prop shaft and
gerar diffs, but it was funny</td>
</tr>
</t></table></td>
</tr>
</t>
</table>





Low-turn motors must be geared lower than stock, as they make their
power from high revs not stump-pulling. Mod motors have less torque
than high-turn motors.



High gearing needs torque to work; SpeedTuned gears give the TL01 super-high gearing.




yes i get what you mean, 40000rpm motor will need a lower pinion to
bring it up to 38000rpm for example...cause if you have a 23t pinion it
will have a sh*t off a time to reach its full potential...




Nismo
 
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<table width="100%" border="0" cellspacing="1" cellpadding="1">
<t><tr bgcolor="#cccccc"><td><center>
Pinion
Gear</font> </center></td>
<td><center>
Stock
Counter Gear</font> </center></td>
<td><center>
Speed
Tuned Counter Gear (29T)</font> </center></td>
</tr>
<tr bgcolor="#ffffff">
<td bgcolor="#999999"><center>

19T </font></center></td>
<td><center>

7.96 </font></center></td>
<td><center>

5.95 </font></center></td>
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<tr bgcolor="#ffffff">
<td bgcolor="#999999"><center>

21T </font></center></td>
<td><center>

7.20 </font></center></td>
<td><center>

5.39 </font></center></td>
</tr>
<tr bgcolor="#ffffff">
<td bgcolor="#999999"><center>

23T </font></center></td>
<td><center>

6.57 </font></center></td>
<td><center>

4.92 </font></center></td></tr></t>
</table>
 

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Low TORQUE too, so takes even longer to speed up.


Also motors are usually most efficient when they are running at 70-90% of their peak (free) RPM... (nb you get Zero power as there's no load @ max free RPM). Running it outside its peak efficiency means its running inefficiently - that's why motors will run hot when wrongly geared.


Because we have huge capacity cells these days, the risk of dumping (batt dying during race) is less and motor manufacturers are designing their modern motors more for performance than efficiency. That only compounds the heat issue.





Generally speaking, low-turn mod motors need lower than 8:1 gearing if its to survive a decent life - some even run 10:1 or higher on small tracks.


But to get crazy power out of them... the ones who 'can' run mod touring cars @ 7:1 and their motors need rebuilding every run. Sometimes there isn't enough left of the motor to be rebuilt after 1 run - "disposable" motors.


Ever seen pictures from a major overseas race? The motor companies will always bring their factory guru to support their team drivers, who get a brand new or at least fully rebuilt motor for each race. That's what you need to compete at the ultimate top international levels - unsponsored racers have little chance.
 
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