TOPIC:

as motors seem to be the hot topic of discussion at the moment, how much grief and how much improvement would it make if i fitted a brushless motor to my hopper.
i know they are expensive but would it be worth the money or would it just blow the gearbox to pieces?

Probably too much for a Hopper...

agemax wrote:

as motors seem to be the hot topic of discussion at the moment, how much grief and how much improvement would it make if i fitted a brushless motor to my hopper.
i know they are expensive but would it be worth the money or would it just blow the gearbox to pieces?

Uh oh, I think someone's got the need ... the need for speed!

It's not _that_ expensive - given that say a 23T motor & an ESC to run it will cost you at least 40 GBP, and a half decent 19T motor & suitable ESC will be more like 60 GBP, and EZRUN combo from Hong Kong (motor, ESC & programming card) at a little over 70 GBP will give a massive performance gain for not a huge outlay... but if you are going for the power angle, make sure you get one ending in .5 (i.e. "5.5T") as these are a full 540 size, the "whole number" motors are reputedly a 380 size motor in a casing made to look 540 size, and have about half the torque. Also get a combo with a 60 Amp ESC rather than the 35 Amp one.

The Grasshopper diff is very tough, provided the driveshafts are straight & you use proper bearings there are no real issues, the spur gear is a little weak though, so if you have any doubts about that, replace it; a steel (or brass) pinion is also a must, as is upgraded battery connectors, mine combos cope fine with NiMH batteries (with the "punch" setting on the ESC turned down), so Lipo isn't essential.

Gearing will depend on which motor you go for - I have a 13T combo in my Bigpig which is probably equivalent to a 19 to 21 turn motor, if you went for that you might get away with stock gearing (18T pinion) ... but is there really any point? it's not that much of an increase for the cost...

On the other hand, I also have a 5.5T in a TA03F drifter and it's completely bonkers, even on the smallest pinion I could get in it (5.5T = 6000kv = 6000 rpm per volt applied = 43,200 rpm on a 7.2 pack, more when it's fresh charged ) - if you went that route (I'd recommend it), I think you'd need to go for the 10 tooth pinion from a Lunchbox & the D2 spacer ... & probably the wheelie bar too

Edou wrote:

Probably too much for a Hopper...

Don't get discouraged, you'll only ever crash it once

so would this fit my hopper, price seems reasonable. is this a good make?
www.ebay.co.uk/...4254wt_932

I'd stick with something more moderate myself...
And (like Jonny said) look for one that's a "half turn" motor. They're better for off road...

agemax wrote:

so would this fit my hopper, price seems reasonable. is this a good make?
www.ebay.co.uk/...4254wt_932

Honestly, I wouldn't. There have been a few reports of "cheap copies" of EZRUN motors - of which I think that must be the current "brand name" - they're infamous for A- poor quality components, build & finish; B- Typographical errors; and C- catching fire right out of the box.

I suppose I'm lucky my "Bullisotrm" combo - complete with its "Smart Barking" feature - only has very poor anodising & chewed up screws on the motor.

I could be wrong, but the "Super Smoot" fan on the one you linked to doesn't inspire confidence.

It's also a whole number (so half the torque of a .5) & doesn't have a programming card.

ok, point taken thanks guys. cant really afford it anyway so i guess i will have to wait till i am loaded and got more money than sense or just forget the whole idea,
as Jonny said i would probably write the poor thing off on the first outing anyway

Edou wrote:

I'd stick with something more moderate myself...
...

Wuss!


Seriously though, "whole number" brushless motors seem to be nothing like equivalent to a brushed motor of the same "turns": my Bullistorm "9T" brushless is more like a 15 to 17T brushed, the EZRUN "13T" brushless in my Bigpig is I'd say about equivalent to a 19 or 21 brushed ...

The .5 motors though, I suspect the equivalence must be about right, or "wrong" the other way - I had to superglue the hard nylon drift tyres down to stop them ballooning & flying off

ooh i have joined the 10k club