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hickston
05-06-2006, 11:49 AM
Anyone got any good tips on Brushless systems? After Destroying another 3 motors this weekend (I'm waiting for my lathe to arrive :/ ), I've decided to invest some more cash (not getting any better if I'm always in the pits).

ESC - to run brushed and brushless good idea?
Motor speeds (some sort of conversion chart???)

Anything else I need to know?

Thanks
Stu

DCM
05-06-2006, 11:55 AM
Brushless motors are rated in KV, which is how many RPM's for 1 volt, this allows you to work out the motor RPM by multiplying the KV rating buy 7.2v. Most of the companies are giving their motors different ratings or winding info but they also supply the KV rating, so if you know the KV rating of a motor, you can work out what rating the ESC is.

I think with Brushless, the more you spend, the better the ESC at the moment. Also, you might want to go for a milder motor initialy, and then maybe get a fater brushless motor later, a lot of people I have seen running them in buggies found them hard to gear.

hickston
05-06-2006, 12:24 PM
Wow, quick response, you must be as busy at work as me then !! :D

I've done a bit of digging and the options seem to be (opinions please)

Novak Sport Plus
Brushed limit 12 Turn
Brushless ????

Novak GTB
Brushed ????
Brushless ????

Nosram Martix
Brushed limit 7 Turn
Brushless 5.5

Nosram Matrix Evo
Brushed limit 5 turn
Brushless 3.5

LRP Sphere

Cost wise, the Novak GTB seems to be the most expensive. Thank god for plastic!!

I found a bit of conversion info too

1 Star = 13 Turn
2 Star = 11 Turn
3 Star = 9 Turn
4 Star = 7 Turn

Do the turns on a brushless match the turns on a brushed?..ie 7 turn (way to quick for me) brushless is as quick as a 7 turn brushed?

Ta
Stu

DCM
05-06-2006, 12:33 PM
I think the motors work in totaly different ways to try to compare like for like. They may have similar RPM properties but feel and operate differently. Be far easier to learn what the KV rating is this would allow for better gearing and motor comparison.

As for the ESC's I would go for the better ones, Matrix EVO and the ilk so if you ever need the extra grunt, you can, plus the ESC operates far more comfortably.

sefton
05-06-2006, 01:19 PM
Hi Mate Craig here from Sunday!

The most popular seem to be the GTB's & the LRP spears (both are highly programable with custom programing at the touch of a button).

The GTB's just a little tricky to fit in the b4, but it does go in!

The gtb can also run brushed aswell, I should probably think the LRP doe's aswell!

I'm at Bury on the 18th, give me a shout for a closer look if you want!

Craig.

hickston
05-06-2006, 01:29 PM
Thanks alot for the info. Also found this

http://www.lrp-electronic.de/e/lis/

It has Brushed and Brushless RPM Charts on it, now I can see what's what.

Ta
Stu

hickston
05-06-2006, 01:33 PM
Hi Craig, thanks for the info too. Wifes nursing a bit of sunburn today :D

I'll probably plump for the Novak GTB because I have GTX's atm and I like them. (tried a few nosram ESC's and didnt like them - especially when they blew up too!!)

Wont be there on the 18th sadly due to Mr Plod not liking my driving (good job he cant see me on the track too!)

Ta
Stu

sefton
05-06-2006, 01:44 PM
Wont be there on the 18th sadly due to Mr Plod not liking my driving (good job he cant see me on the track too!)

? you band then?

Yeah got a bit of a t-shirt tan myself!

Good day though!

Craig.

Chris Doughty
05-06-2006, 01:52 PM
for a 'reasonable amount of speed for off-road'

you wont go far wrong with an LRP Sphere Comp and a LRP VECTOR 3-star brushless motor.

performance of the 3-star is comparable to a 9 turn brushed motor, but you will get more runtime out of the 3-star.

the Sphere Comp esc is very good running brushed and brushless motors, when running brushed you simply connect yellow and blue to the -ve terminal on your motor, with the Novak you need to connect all the 'burshless motor wires' to the -ve tab on your motor and then have the red battery wire Y onto the motor, I would think it would be a lot harder to switch between brushed and brushless with the Novak.

hickston
05-06-2006, 02:00 PM
Wont be there on the 18th sadly due to Mr Plod not liking my driving (good job he cant see me on the track too!)

? you band then?

Yeah got a bit of a t-shirt tan myself!

Good day though!

Craig.

Yup, no details required though, suffice to say I've 17 months to go :/...Hence having to bring the wife, the son and the kitchen sink to meetings.

sefton
05-06-2006, 03:03 PM
you from the bolton area?

AndyG
05-06-2006, 03:30 PM
I run an LRP Shpere Comp in both my ZX5 and my B4, and I'm not going back. Nothing to do between rounds but sit back and enjoy watching some bloke skimming a motor (I have a lathe for sale btw), and Kirky rebuilding another gearbox. :P

I ran a 4 star (equivalent of a 7 turn) in my B4 on Sunday, "for a laugh", and it was silly. Ran it on an 18 pinion because I couldn't get the motor close enough to the spur with a 17. As Mr Doughty says, the 3 star is probably about right for most things.

sefton
05-06-2006, 03:44 PM
Nothing to do between rounds but sit back and enjoy watching some bloke skimming a motor

Yeah Ive now decided to take a magazine or somthing to read between rounds!:D

Craig.

Cotti
05-06-2006, 03:49 PM
Yeah ive found zero maintinance to be a real boon to! Im running a LRP 3 star in my ZX5 but its cogging a bit with the kit pinion (17) what are you guys using?

sefton
05-06-2006, 04:06 PM
What do ya mean by clogging?

I'm running a b4 with a 6.5 novak and a 81 18 gear. It doesnt feel like theres enough punch, going to have a fiddle with the custom setups and try a 19 pinion.

Craig.

DCM
05-06-2006, 05:17 PM
cogging is like a stuttering at low speed. There can be many causes for this, over-geared is one, plus check all your solder joints and connectors are good and solid.

hickston
08-06-2006, 02:28 PM
for a 'reasonable amount of speed for off-road'

you wont go far wrong with an LRP Sphere Comp and a LRP VECTOR 3-star brushless motor.



Ok, got ESC and motor. Fitted and it goes very quick (too quick for me really!!). I'm also waiting for a 1-star to arrive, but there out of stock. Next Question...

Now my diff either isnt working or is rough. Is this bcos there's no weight or anything in the motor? or should I be looking to take it apart (I've tried adjusting) and clean/grease etc?

Thanks
Stu

Chris Doughty
08-06-2006, 02:55 PM
with a brushless motor in, you will find that you need to hold the spur gear to test the diff.

with no comm/brush resistance the motor does not 'lock' the transmission as much as a brushed.

having a 'rough' diff is not all that bad, as long as its not terrible, mine is always pretty rough, sometimes it helps deliver the power

hickston
08-06-2006, 03:21 PM
Thanks. Diff is ok now (well, not that it wasnt ok)

Ta
Stu