1. ## Spur gear sizes

I know that the stock spur gear for the 1/16 e-revo is 50t but what does changing the spur gear to a 55t or 45t do?

2. Change your gearing for more torque and lower top speeds or less low end torque and higher top speeds. All depends on your pinion and spur.

3. 55 = Slower, less heat
45 = Faster, more heat

4. With the 45 you are gonna get more acceleration tho correct? and less top end? and the 55 with be higher top speed but less acceleration? Or am i backwards? lol

5. Ok so this is what i understand then, 45 more acceleration lower top end and 55 less acceleration higher top end?

6. That might be backwards im not sure! I think the closest to 1:1 you get with the spur/pinion the higher your top speed will be. But gearing confuses me a bit.

7. Well thanks so much for the info.

8. Yeah I'm pretty certain 45 means more speed.

The SPUR can be thought of as the drive shaft... you want that thing spinning faster if you want more speed. So if it has LESS teeth, it will do 1rpm faster than one with more teeth. Thus, the 45 is a faster setup where the 55 is slower. As a result, 55 would be a bit more torque compared to the 45.

9. Originally Posted by korn0307
With the 45 you are gonna get more acceleration tho correct? and less top end? and the 55 with be higher top speed but less acceleration? Or am i backwards? lol
You got it right.

Originally Posted by krallopian
Yeah I'm pretty certain 45 means more speed.

The SPUR can be thought of as the drive shaft... you want that thing spinning faster if you want more speed. So if it has LESS teeth, it will do 1rpm faster than one with more teeth. Thus, the 45 is a faster setup where the 55 is slower. As a result, 55 would be a bit more torque compared to the 45.
You got it!!

10. so the 45 would give it more acceleration then the 55 but does that mean 45 would still have a greater top speed though or would the 55?
I'm just trying to fully understand how the set up works.

11. 55 gives more torque
45 give more speed

Think of it this way...
Say you are and ant and the 55 is a basket ball. How long would it take you to walk the equator?
Now, you are still an ant and the 45 is a base ball. How long would it take you to walk the equator?

12. ok awesome. thanks so much!

13. No problem!
Remember, this analogy only works for spurs... not pinions!!

14. Originally Posted by Jimmie Neutron
You got it right.
At least i wasnt 100% wrong! lol

15. What do you mean? How would pinions work then, if you dont mind me askin?

16. The fewer teeth that are on the pinion the more times the motor has to turn to turn the spur/drivelines 1 turn.

17. Originally Posted by zaloria
What do you mean? How would pinions work then, if you dont mind me askin?
bigger pinion means faster

smaller pinion is more torque, less speed

18. So, let's say Dual 2200mah 7.4V ******* Lipos, with the Speed Pinion, and Series Connector. Stock Spur is 50, and I'm concerned about heat. I have access to 60t, 45T, and 55t Spurs. What combos Should I be looking at with Spur and Pinion?

I like Tried and True rather then Trial and Error.

Mike

19. I run 23/50 with 2S 2200's without any heat issues.

In parallel, of course.
The stock ESC will not handle LiPo in series.
The motor may for speed runs (4S) but not for long.

20. id try the 55t or 60t spur, i think ur gonna have heat problems anyways if u run them in series, id just run them parallel and u could put the stock pinion back on and run a 50 spur, i run a 28t pinion and 45t spur and i can usually keep my motor at a decent temp running 2 spc 2500mah 2s in parallel

21. with my set-up i do 40 plus per gps and alot of wheelies

22. Originally Posted by Jimmie Neutron
I run 23/50 with 2S 2200's without any heat issues.

In parallel, of course.
The stock ESC will not handle LiPo in series.
The motor may for speed runs (4S) but not for long.
Originally Posted by mervraptor22
id try the 55t or 60t spur, i think ur gonna have heat problems anyways if u run them in series, id just run them parallel and u could put the stock pinion back on and run a 50 spur, i run a 28t pinion and 45t spur and i can usually keep my motor at a decent temp running 2 spc 2500mah 2s in parallel
I have both a Mamba ESC and Trinity Brushless from a Trinity Now, and a Novak ESC and Brushless conert for a Losi 8ight laying here if things go belly up on the VXL ESC or motor. That being said has anyone removed the Heatsink on the VXL and modded in their own Heatsink? Why exactly does it not handle the lipo in series beside Heat? Their has to be a sure fire way to dissipate the heat with a couple of quick mods. Maybe a decent Heatsink and a set of fans for both the Motor and the ESC?

23. Large heat sinks are not going to solve the heat issue... it is just a band-aid.
Fans... lol. You are moving more air across the heat sinks at speed than any fan that fits can at 6v.

24. You don't want to mess with fans or heat sinks. Sure different fans have different blade designs and efficiency ratings but that too isn't a good idea to mess with. The electronics in an ESC that have no fan, are spec'd to work to a specific temperature, if you add a fan to the heat sink, you lower the "outer electronics"s temps but not the temps at the core, and thus you are breaking down the components even though a sensor says otherwise. If you want to run cooler, get a "more capable" ESC, and you remove any risk of heat damage. I get scared when I see people modding things that are running such incredible amounts of power through them, these aren't your typical calculator style electronics here.

A heat sink on a motor is a different story but shouldn't be required unless you're planning on running way above spec for long periods of time at WHICH point you're already aware that you will soon be replacing parts anyway.

I've worked on computers far too long and I'm running a 3.2ghz processor at 5ghz right now with some minor voltage adjustments across the board, I have insane cooling with insane cooling FOR my cooling and so many failsafe's I could be a star "electronics nerd" on one of those movies, HOWEVER I know the limits of the equipment and SURE I can run at 6ghz, but you'll never see me on a forum telling someone, "yeah yeah yeah, just hook that fan in to the 12v with a mod plug instead of the 5v it wants, it'll spin MUCH faster and you'll be able to keep the heat sink much cooler THUS allowing greater overclock!" ..... some 11 year old sees this, and his cpu catches on fire and burns his house down! SO........... don't mess with cooling if you don't know what you're cooling in the first place and most CERTAINLY don't mess with things being powered by batteries that are capable of throwing 50+ amps out of them.

I'm typing this in good mood, I'm not trying to be rude or condescending so I hope you understand I'm trying to give stern warning but with the best of intentions! =) *cheers

25. Originally Posted by krallopian
A heat sink on a motor is a different story but shouldn't be required unless you're planning on running way above spec for long periods of time at WHICH point you're already aware that you will soon be replacing parts anyway.
Interesting, Makes me wonder why Traxxas puts out a Heatsink for the motor (TRA3374) as an aftermarket? Also why Most other Brushless systems come with Heatsinks and Fans right out of the Box. Mamba, and Novak come to mind. But from what your saying, If I wanted to run 2 Hot Lap 20 Minute runs back to back I'm looking at the wrong Motor and ESC? I should be swapping right out of the box? That Attaching a Finned Heatsink to the motor After stripping the can and micro polishing it and using a trusted Compound such as Arctic Silver Thermal Adhesive wouldn't help to dissipate heat from the Motor? And I noticed on my ESC their is a small heatsink on the top. Surely it can be removed and replaced with 2 Mosfet Pure Copper Heatsinks and AS Thermal Adhesive? I mean, it would allow it to stay cooler for a little longer no?

Originally Posted by krallopian
I've worked on computers far too long and I'm running a 3.2ghz processor at 5ghz right now with some minor voltage adjustments across the board, I have insane cooling with insane cooling FOR my cooling and so many failsafe's I could be a star "electronics nerd" on one of those movies, HOWEVER I know the limits of the equipment and SURE I can run at 6ghz, but you'll never see me on a forum telling someone, "yeah yeah yeah, just hook that fan in to the 12v with a mod plug instead of the 5v it wants, it'll spin MUCH faster and you'll be able to keep the heat sink much cooler THUS allowing greater overclock!"
I too build custom computers and OC the heck out of them. I'm a member over on 411overkill.com and have a thread their about one of my PCs, I don't know if I can link to it because Profane language is used on that site. But if your interested you can PM me. Right now i'm on an EVGA 780i with a Wolfdale E8300 Maxxed at 4.8 for 4 hour benches and 3DMark scores. But constant run at 4.3, (On air mind you). I'm currently in planning phases for a new build as EVGA no longer stocks the 780I and they are planning a swap my 780I out to an X-58 Classified for shipping only. Leaving me to buy a new CPU, RAM, and Cooling System.

Originally Posted by krallopian
I'm typing this in good mood, I'm not trying to be rude or condescending so I hope you understand I'm trying to give stern warning but with the best of intentions! =) *cheers
I absolutely understand exactly where your coming from. And didn't find you condescending at all. Too many children on the Internet see a How-to and start ripping into mom and dad's electronics trying to make a Ferrari out of a Volkswagon.

But being that I never leave stock alone and Upgrade or Mod everything I get my hands on I can't help myself. I took a Tmaxx 3.3 and turned it into a BB UE Supermaxx in less then 1 month of owning it. I've got a Micro T all Aluminum and Lipos, a Mugen with a BB S7 Worlds in it. And in 15 minutes I can swap it out to a Novak Dual lipo system.

Mike

26. Thanks Mike, I appreciate everything you said! I wanted the X-58 but I got the P67 Deluxe and it's the best "Deluxe" board I've ever bought.

AS for heat sinks on the ESC... the caps and other components used are super low quality, so yes although an aftermarket hsf combo would help dissipate the heat think of this:

You have a 2" thick piece of iron. Put a flame underneath it, and a small heat sink on the top. Call that "normal" cooling. The heat sink does it's job, and helps take the heat away. Polish the top of the iron, put the exact right amount of thermal compound on, now it works better to keep the temp of the iron down by 5° and that's awesome! NOW put a sideways mounted fan on the heat sink blowing air across the fins, even better! HOWEVER, the BOTTOM where the flame is, is STILL just as hot. The top is cooler, but the bottom hasn't changed temps at all. NOW raise that temperature (in rc terms, more powerful battery, higher gearing, whatever you want) and the heat sink will also raise in temp, but suddenly you're MELTING the iron on the bottom, but it's not showing through on the heat sink side.

That is the problem with putting aftermarket cooling on something like an ESC. You will certainly improve the "outer electronics" - as I called it - temps, but the core will fail. You don't want to spend the money on extra cooling, \$5 heat sink \$5 shipping, \$12 fan, \$5 shipping, thermal compound etc... when all you need to do is get a better ESC.

It was a poor metaphor but I'm sure it gets my point across!

*cheers

PM sent!

27. Said very eloquently.

Mike

28. Lol getting a better ESC and motor would be a lot simpler than adding a bunch of fans and heat sinks lol. All that computer and electronics talk has got me all confused. lol

29. i usually put a ice pack under my body it keeps everything pretty cool

30. That's awesome! Adds weight but the cooling more than makes up for it, pics?

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