emp 2 speed results... help

[mdyates]

Hello all, new to the forum. I have a 36v 95 Medalist, 4 inch lift, 22 tires, 2010 trojan batts and stock controller with new 4 ga wires. Before last night I was getting 15 mph out of her.

Well, I installed the lr5.4 motor from emp that is supposed to to 16 mph in low and 24 in high (stock tires +2mph for 22") On a full charge I'm getting 18 in low and only 21-22 mph in speed mode. No brake drag or weird stuff going on I have 20 psi in the tires!

Based on what they said I shouldve expected 26 mph or so....

Now I must say, they are a great company and great to deal with. AND I have some crazy torque now.

But why not the results they claim and they don't really have a reason? Do these new motors have a break in period?

[CART-ZILLA]

what size amp is your controller???

[mdyates]

stock, 375 i believe..? Would a controller help with top end? I know it would torque

[CART-ZILLA]

HHHHMMMM...... good question i'm thinking about getting a 2 speed or a pq bandit ....

[madoc1]

your controller is probably 275 amps, and would think you will need bigger to get full potential out of the motor. think your best bet is to call emp and see what they say.

[scottyb]

Every cart is a little different. You could put that motor on 5 different carts and get 5 different results. Which is why the hardest question in tech support is "how fast will this make my cart go?" Variations of a 25% are not unheard of.
When was the last time you changed your axle bearings and differential fluid?
Can you push the car easily with one hand on flat ground?

[mdyates]

Thanks for all the replies, yes I can push the cart on flat ground, not easliy however... Don't think my brakes are dragging. Might be a good idea to clean/adjust the drums? Also, I have no idea about the condition of diff fluid. What fluid should I use, 30w? If my diff fluid was in ok cond, would it help to change? I'll also check my toe in as well.

[scottyb]

Alignment and tire type, condition, and air pressure all play a part .... again this is why Techs cringe when somebody asks how fast.... Many professionals like to answer on the slow side of the estimate. That way if you get more your happy!

Jack it up and see how much bearing and brake drag you have.

[mdyates]

Scottyb, thanks! My front tires roll very well, how do I check the rear without damaging anything?

[dougmcp]

The stock controller may be holding you back a little.
Put a voltmeter on the pack and take it for a ride.
Your starting voltage should be in the 38.2v range and your voltage drop under full throttle should be less than 15%, at cruising speed it should be around 36v.
When you changed your cables did you do all 11 of them or just the batteries?
2ga cables from the controller to the motor will also help a little.