RPM

[Admin]

I ve seen on some websites, most websites, that bit char-g motors go at an amazing 22,000 RPM (2.2motor). Is this accurate or is it more likely to be 2,200 (2.2)?

[jamiekulhanek]

Nah thats true. 1.0=10,000RPM 2.2=22,000RPM 2.6=26,000RPM 3.0=30,000RPM.

You are probably thinking that it is impossible for a motor to do those speeds? Maybe a car engine, but small engines rev really high.

The world is mine

[Barrelll]

yep jamies got it right, 22 000 rpm, gotta love the speed, hehe 🙂

27MHZ 3.5 Honda Accord (Custom Exhaust and F1 Wing)
35MHZ 1.0 Battery Modded Castrol Supra
45MHZ 2.2 Custom Painted Yellow and Black WRX
57MHZ 2.6 Booster Trueno
Mini Z Blue WRX (Lights, Gold alloys, Exhaust)
Mini Z Castrol Supra + all mods (Coming)

[dgs73]

is there any reason all 3 of my cars would be
seeming to lose rpms?? first off, quick as…
lately tho, they tend to be a fair bit slower.
tried greasing the axle, rotating the motor( that
“3 o’clock” position works, but only for a little while, it seems),new AA’s in the charger, etc.
Any ideas????

[Impreza]

Did you do anything to the bats (NiCD’s) in the car?

Impreza :smiley16:

[PandaBear]

How old are the cars, David?

Nicads do have a finite life, probably around the 500-cycles mark (maybe even less given our quickcharge abuse). If they’re well-used cars then perhaps you’ve charged it 500+ times already and the cell is getting tired.

[PandaBear]

But no fear!

Just buy a $24 KIT Racer car from KMart/TRU etc and that’ll score you a new Tomy cell and a new 2.2 or 2.6 motor.

Instant tuneup kit! 🙂

[PandaBear]

Quote:

Nah thats true. 1.0=10,000RPM 2.2=22,000RPM 2.6=26,000RPM 3.0=30,000RPM.

You are probably thinking that it is impossible for a motor to do those speeds? Maybe a car engine, but small engines rev really high.

Motors can rev high as there’s no reciprocating parts, its just a balanced spinning axle vs a piston engine whose bits move up/down. Double the rotational speed and it becomes 4X the forces on the crank/conrod/gudgeon-pin/piston.

That’s free running RPMs anyway… when the motor is unloaded.

[Lazboy]

does any one know the RPM of the wheels when running ????

CompactChar-G 40Mhz S2000 range mod, spring suppention
Bit Char-G 57mhz Booster Fairlady Z

[micro_Amps]

You can work that out by dividing your motor speed by the gear ratio you are using.
eg micro B3.0 is 30,000 rpm / 9.86 = 3042 rpm at the wheels
BitChargUK have a page where all the ratios are worked out

[Shypo]

also QFM have a page for all Bit Char-G and Bit racer axles and there RPM to there corresponding pinion and tyres aswell i think?

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Go Fast, Be Free with Low CC

Undisputed Post Pimp

[Cranga]

[/quote]

Motors can rev high as there’s no reciprocating parts, its just a balanced spinning axle vs a piston engine whose bits move up/down. Double the rotational speed and it becomes 4X the forces on the crank/conrod/gudgeon-pin/piston.

That’s free running RPMs anyway… when the motor is unloaded.

[/quote]

Thats right pandabear! just like the marvelous rotary engine! Invented by the top bloke Professor Wankel

Bap Bap Bap

[Cranga]

that was meant to be w a n k e l.
i guess you cant say wank in these forums! how about any other swear words?

Bap Bap Bap

[dgs73]

Oddly enough, two of the cars are less than 2 weeks old, and would be lucky to have topped the 100 charge mark. The Nicads have had nothing done to them (in reply to Impreza) but maybe they are abit weary.

[Impreza]

??? What are the freq’s of the cars? Just a hunch, you seem to know what you are talking about so I will not ask you if your axels have a large hairball stuck to them;)

Impreza :smiley16:

[Barrelll]

lol, never underestimate the hairball 😉

27MHZ 3.5 Honda Accord (Custom Exhaust and F1 Wing)
35MHZ 1.0 Battery Modded Castrol Supra
45MHZ 2.2 Custom Painted Yellow and Black WRX
57MHZ 2.6 Booster Trueno
Mini Z Blue WRX (Lights, Gold alloys, Exhaust)
Mini Z Castrol Supra + all mods (Coming)

[PandaBear]

Quote:

that was meant to be w a n k e l.

Rotary engines still have to move their rotors, they just move in an eccentric orbit. The crankcase is like a figure-8 and the triangle rotor shifts back-n-forth as the crank rotates.

Nah, the only true rotary engine is a gas turbine. Pure simple spinning action: 50,000 rpm is their *idling* speeds!! :shy: Played with one at uni before… quite an impressive gadget.

[PandaBear]

Quote:

i guess you cant say **** in these forums! how about any other swear words?

****! what are you ****ing trying to do to this ***ing forum my dear *****??! Whatta *****, don’t be a ****ing bad example to all the **** kiddies reading this ****site.

(Yes, I deal with ****ing Truckies a lot. :blush:)

[micro_Amps]

I think we’ve seen from the ‘What age are you’ posts that there aint many ‘kiddies’ here:)uA

[dgs73]

in reply to Impreza, the cars are 27MHz and 40MHz, so yes they are Compacts not Bits, not that that should make a major difference.
And yes, lose crap and hair, etc. doesnt even get a chance to accumulate!! Im guessing maybe something real small may have worked its way inside the motor, if thats possible.

[dgs73]

nice to know im not the only thirtysomething chasing these cars around!!

[Impreza]

Compacts should not make a diff. I didn’t know that they came in 40 MHz? Having 2, 27 MHz in the same area can effect performance. Plus sometimes the 27 MHz cars can stumble a bit:( Maybe try the cars in different rooms. Try the basement if you have one???

Impreza :smiley16:

[Shypo]

compacts come in 27 and 40, microsizers come in 27 and 49 other BCG comes in 27, 35, 45 and 57

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Go Fast, Be Free with Low CC

Undisputed Post Pimp

[Impreza]

Nice to know that there is a 40 Mhz bit option out there:)

Impreza :smiley16:

[Shypo]

the 40,45 and 49 cars pretty much all interfere which reallllly sux. i dont understand how a mini Z can run on like 27.145 and another on 27.348 or whatevr it is and there is no interference:question:

—-
Go Fast, Be Free with Low CC

Undisputed Post Pimp

[Impreza]

Sounds like a question for Panda or micro Amps?

Impreza :smiley16:

[mastercool bowker]

im a kid

[mastercool bowker]

8 1/2yrs old and…ah, never mind.

[mastercool bowker]

lazboy, go to ‘www.tinyrc.com/qfm/racing’
It tells you what speed ur wheels are spinning with each motor and with whatever gears.

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Eat right,exersize…die anyway!

[Author]

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