11 replies to this topic

[FVracer]

I built a motor for RetroPro to SCRRA rules - X12 PS arm (reconditioned by Alfa) in a PS mini can. BB both ends and copper hardware. I used Champion light springs and Koford BFs. I broke it in and got the amp draw down to 3.2 after not much time on my power supply. I thought I'd run it in on the track I mounted it in the chassis, soldered, and tested it. It drew 5.4 and it was "free" not against a spur.

 

What do I need to look at? It's for the Caribbean Retro Championship and don't think I can get another motor in time. This combination is not stocked by distributors.

 

Thanks.

[MSwiss]

Make sure there isn't any comm dust, or other debris, in the slots.

[Robert BG]

Have you ran it on the track at all yet?

[Cheater]

Diana,

 

Try another couple of sets of brushes and see what amp draw you get from them.

[Rob Voska]

Did you bind the can when you soldered it in?

[FVracer]

No track test yet. I'll unsolder, check for binding, check for trash in the comm, and replace brushes. We'll see what happens.

 

In any event your help is very appreciated.

[John Streisguth]

Diana:

 

I would be glad to send my RetroPro motors to you. I raced this past weekend at RetroPalooza and the X12 is fast; my chassis was not competitive.  

 

I also have a motor with a Big Dog arm, in case you find the X12 is a bit "too much." LOL.

[gc4895]

Is the X12 in the mini-can competitive with an X12 in a C-can? Anybody make a comparison of these? 

 

I weighed my mini-can motors at 20 grams vs C-can motors at 28 grams so they are lighter. I'm just wondering if, in the circumstances where the formula is simply "any X12 motor", the mini would offer an advantage?

[FVracer]

Mark,

 

The rules in SCRRA RP require a PS mini-can.

 

The motor is working well now. The best result was changing brushes to PS Goldust and rotating the endbell 180 degrees. I tried another new set of Koford BF with a little improvement. Then I  put in the Goldust and there was significant improvement. I rotated the endbell 180 degrees and the motor spun up nicely. It's now pulling 2.7 and it hasn't yet run on the track.

 

Before doing the reassembly I cleaned the comm slots and wiped the comm down with PURE. Since the endbell might have been moving even with the can screws I used a little epoxy in the screw holes of the endbell before reassembly. Probably be a bit difficult to disassemble but the race is close.

 

Happy now. Thanks for the help and hints.

[Steve Boggs]

You rotated the endbell and it got better? Were the lead wires soldered backwards making it run backwards?

[FVracer]

No, the lead wires were correct. I think the 180 degree switch probably just corrected a tilt that I hadn't detected before. I probably could have rotated it back and made sure it was absolutely straight.

[Jason Holmes]

Diana

 

Most of my Little Motors (R/P) draw 4-6 amps at 5 volts when breaking them in 

 

Jason