Motors, "zero timing" ?

[buspor63]

You know, just one of those things I want to know, but don't have the instruments to check.

Are slot car motors "zero timed"? Meaning, do they have the same performance regardless of how they are wired? In particular, I'm thinking Slot.it Orange and H&R Hawk because they are double ended.

Whattaya think?

[DHansen]

I'll try to answer this to the best of my abillity. Based on my experience with 16D and supper16D motors the com timing can be anywhere from 10deg. to 45deg. advanced, and will run slower if run backwards, The more advanced the timing, the slower it will run in reverce direction. [and it will all so get hotter quicker] This is only a problem if you install your crown gear on the wrong side of the pinion on an inline type chassis and cross the wires. The higher timed the motor is the more RPM's the motor will make [running the correct direction] but at the sacrafice of low RPM torque, or out of the corner punch. Higher timed motors work best on tracks with longer streights. Low timed motors work best on tracks that are short and twisty like most home tracks. So I'm guessing that most home set or RTR cars have motors that are low timed motors and will run only slightly slower if running backwards. I have done this to tame down cars that had to much motor. All so note that most 16D style motors are running at 40 to 60 thousand RPM's and most home set cars are running at around 15 to 20 thousand RPM's. The lower RPM's the motor turns, the closer to zero the timing is. Usually. There are all so some other factors like the size of the wire used for the winding on the armature. But that's another long and more technical story. Hope this helps.

[RichD]

Advancing the timing can really wake a motor up. When I raced 1/24th cars I ran my 16Ds at 35 degrees advance and my S16Ds at 45 degrees where the rules allowed that. Any more advance and the motors would be likely to burn out. When I pushed up the timing I got both more RPMs and more torque. If the track voltage was down for some reason the high timed motors would really fade out. I do have a timing gauge for 1/24th motors. Some HO cars have a variable timing feature with an endbell that can be rotated, in that case some motors will be faster with the timing advanced and some won't. All of the stock 1/32nd motors that I have examined have had neutral (more or less) timing. I only tried advancing the timing with one motor and that had no effect. We only race unopened motors.

[Old Reb]

I see the timing gauge is from Bullet Raceway in Decatur, GA! I spent many hours there racing and hanging out with Ray, Bill, and Bob. Those guys were slot racing pioneers in the US, and were on the Champion factory team back in the day. Some of the nicest and most knowledgeable racers I have known. I was sorry to see the track close. This was Ray's second time around track and a good memory from the second golden age of commercial racing in the Atlanta area.

[buspor63]

[hillbilly]

At our local track we use to run the 18000 rpm H&R Hawks, it was not consistant with all of the motors, but several were found to have a fast side and a slower side. It was noticable to the ear when you put them on a power supply at 13 volts. We would see cars pick up a 1/2 a second. But these races were at a commercial track dont know what you would see on a smaller track. But there was was definately some difference in the speed of the cars depending on how they were wired. Hillbilly

[Abarth Mike]

There is or used to be a program called G-Tune. There maybe other 'pitch' instrument tuning programs. If it is still out there and you have a microphone for a computer you can check/compare motor rpm backwards and forwards as yes sometimes there is a difference. Only valid for in-line motors thought unless you are scratch building!

Mike

[Abarth Mike]

[/quote]

Are such widgets still available? I'm a closet tool geek!

[DHansen]

My timing gauge is exactly the same [from Bullit Raceway and everything] but I got mine from a raceway in Iowa. Point being is I'm sure any commercail raceway or one of the online venders can get you one. I don't see a part number on it so you will have to search for "commutator timing gauge".

[Abarth Mike]

I just discovered that my "office" protractor convergence point is exactly half of the 12.72mm of a FC-130 arm. So sometime let the drilling commence. Then I have to work on a pointer. The nice thing with the one pictured is that the line go right to the convergence point.

[SpeedyNH]

i used to make my own. they didn't look a lot different. one thing i used to do with the pointers on the protractor-based ones was to put a tiny piece of piano wire in to slide into the gap between the com segments to take some error out of it. later i just did it by eye- whatever i could get out of it with the wires stretched in the direction of interest.
speedy

[Abarth Mike]