Etek Motor Help

[JQmile]

I have an Etek motor that I bought about 10 years ago that I am finally just getting running on a test stand.
So first, there are no positive and negative on the terminals, can you hook it up either way, with it just changing direction?
Also, there's a little squeaking if you turn it in one direction so I'm a little worried that all the grease or whatever was used for lubrication is dried up, is there any maintenance I can do after having it sit for so long? For those not familiar with the motor, this is it:
Robot MarketPlace - Etek Motor

Current plans are putting it in a go-kart with 3 12v motorcycle batteries

[Piotrsko]

Looks brushed so polarity is probably not important.

I would add one drop of light oil to the bearings on both ends. Spin it with a hand drill both directions for a minute or two.

Since it is a low voltage motor, I would use a couple of D batteries to run it on testing

[JQmile]

Thanks! Once I'm ready to amp things up (ha) with the motorcycle battery (I just have one 12v so far) can I just use something like a drag race car battery cutoff to turn it on and off, or do I need a contactor switch? I have an Alltrax controller for it, I just can't find it after my last move (d'oh).

[Stubby79]

It can be spun both ways.

Bearings are sealed. You can potentially pull out the seal and get at the grease and bearings inside. I doubt it's bearings though, if it's only doing it in one direction. Turn it by hand and see if it does it at a certain point, or if it's a continuous roughness. It might be something minor that will go away if you give it some run-in time on your bench.

Motorcycle batteries will only last maybe a minute or two and probably over heat and ruin themselves in a hurry, under load.

You want to be careful using only a switch...You don't want to exceed the motor's current limit (330 amps) much if at all, and with just a switch there's nothing to stop it pulling more. At least the motorcycle batteries won't put out that much for long, if at all.

Batteries are always the hard or expensive part to anything of noticeable power.

[JQmile]

Originally Posted by Stubby79

It can be spun both ways.

Bearings are sealed. You can potentially pull out the seal and get at the grease and bearings inside. I doubt it's bearings though, if it's only doing it in one direction. Turn it by hand and see if it does it at a certain point, or if it's a continuous roughness. It might be something minor that will go away if you give it some run-in time on your bench.

Motorcycle batteries will only last maybe a minute or two and probably over heat and ruin themselves in a hurry, under load.

You want to be careful using only a switch...You don't want to exceed the motor's current limit (330 amps) much if at all, and with just a switch there's nothing to stop it pulling more. At least the motorcycle batteries won't put out that much for long, if at all.

Batteries are always the hard or expensive part to anything of noticeable power.

Cool thanks for the info! The Go Kart will still have the 12hp gas engine on it, so the electric motor will only be used for an acceleration boost. Doubling the horsepower and tripling the torque just sounded like fun. Based on my math I'd have about 12 minutes at 100-150amps but I could be off. I may run it electric only just to see what happens but for now the plan is just to use it as E-nitrous

[samwichse]

Originally Posted by JQmile

Based on my math I'd have about 12 minutes at 100-150amps but I could be off. I may run it electric only just to see what happens but for now the plan is just to use it as E-nitrous

You can't discharge the batteries past ~50% unless you want them to die VERY quick deaths. And they will sag severely under that kind of load, so I wouldn't expect more than 2/3 the nameplate voltage out of them.

[JQmile]

Thanks for the advice guys, as you can tell I'm a noob to electrics.

[Stubby79]

If you’re using it for moments at a time, car batteries aren’t very heavy and can put out a lot of amps...plus easy and cheap to find.

I doubt there’s more than about 20ah in a motorcycle battery, and that will be cut in half or less under a heavy draw. Not that a car battery is going to be a lot better. Agm racing batteries are probably the way to go, but not cheap. Then again, for that kind of money, you might as well use lithium and save some weight. $$ brings us back to using car batteries....

[JQmile]

Originally Posted by Stubby79

If you’re using it for moments at a time, car batteries aren’t very heavy and can put out a lot of amps...plus easy and cheap to find.

I doubt there’s more than about 20ah in a motorcycle battery, and that will be cut in half or less under a heavy draw. Not that a car battery is going to be a lot better. Agm racing batteries are probably the way to go, but not cheap. Then again, for that kind of money, you might as well use lithium and save some weight. $$ brings us back to using car batteries....

It's a 35ah AGM so it's decent, but like you said, not a car battery.....got one to try at $50 as a factory blemish cause one of the terminals was messed up.

[samwichse]

Originally Posted by Stubby79

If you’re using it for moments at a time, car batteries aren’t very heavy and can put out a lot of amps...plus easy and cheap to find.

I doubt there’s more than about 20ah in a motorcycle battery, and that will be cut in half or less under a heavy draw. Not that a car battery is going to be a lot better. Agm racing batteries are probably the way to go, but not cheap. Then again, for that kind of money, you might as well use lithium and save some weight. $$ brings us back to using car batteries....

https://www.hybridautocenter.com/HAC...ule&Itemid=605

Two of those modules rewired from the factory 2-series, 2-parallel configuration to 4-series gets you a 30v, 29 Ah lithium battery for $220 that does 270A peak and 120A continuous output. Add something like a cell log 8s to check your balance.

Just looking around, most motorcycle batteries look like they're rated 80-100 cranking amps.