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View Full Version : Advancing timing on XMods motors


neurokinetik
12-07-2003, 12:24 AM
Since people have been asking about it, here it is: All you are doing is twisting the commutator relative to the rest of the armature. When you advance the timing on the motor, you gain top speed (in the forward direction, while losing speed in the reverse direction), at the expense of a little bit of torque. There are limits to how much advance you can get away with before the motor starts running poorly. Stick with what I show in the pictures and you will find the gains to be worthwhile without being too risky.

The first two pictures show the armature with neutral timing. Note how the commutator contact is centered in the gap between the poles of the armature.

http://users.adelphia.net/~neurokinetik/neutral_timing.jpg
http://users.adelphia.net/~neurokinetik/neutral_timing2.jpg

The next two show the timing advanced. I try to twist the commutator so that the contact is even with the edge of the pole.

http://users.adelphia.net/~neurokinetik/timing_advanced.jpg
http://users.adelphia.net/~neurokinetik/timing_advanced2.jpg

To (gently) twist the commutator, I just grasp it in my fingers, while holding the pinion gear in my other hand. It is possible (and advisable) to do the timing adjustment without removing the armature from the can, as pinion removal tends to force the brass spacer at the front of the armature into the armature windings, causing excessive longitudinal play within the motor. Note that there are small nubs on the end of the commutator that hold it in a neutral position. When you twist the commutator, these nubs will break, allowing it to move. Once you have it where youwant it, you could use a drop of CA glue or the like to hold it in place (towards the windings), though I don't bother, since the rotational force of the motor is primarily on the armature poles, and the commutator is just along for the ride.

Last thing to note is that you create a bit of slack in the windings by doing this, so I tend to try to pull them tight at the contacts, as shown in the bottom picture.

AUDI-TT
12-07-2003, 12:28 AM
everytime i open and close a motor, it doesnt work anymore, i cant get the brushes set in properly, do u have any tips???

neurokinetik
12-07-2003, 12:47 AM
When you remove the endball, leave the caps soldered to the can, and remove the endbell separate from the brushes. After removing the endbell, just gently pivot the brush assembly out of the way. Try not to let the brushes get bent at all. When rotating them back into place, you will need to spread them gently, so that they clear the spacer washers at the bottom of the commutator. Once the brushes are in place, then put the endbell back on. If you do this properly, everything will work when you get it back together.

FastRSX
12-07-2003, 01:00 AM
neurokinetik thanks for the pictures. I was trying to advance the timing with the brushes but caused to many problems.

Which motor were you installing the SpinBrush magnets into. Stock, Stage 1, or the Stage 2 motors?

neurokinetik
12-07-2003, 01:12 AM
I've tried them in just about everything, actually. The only thing they didn't work well in is my custom 25 turn motor.

I really like them in the stage 2 drag motor with the timing advance.
With that setup, I dragged against a pretty much identically modded Supra with a stock stage 2 drag, and walked him pretty bad from the start and kept right on pulling until the end...

sherifx
12-07-2003, 01:37 AM
What do you think the max timing is? I only ask b/c I assume the picture you posted is a fairly conservative setup. Thanks


sherif

btw, HUGE thanks for posting this info up!

neurokinetik
12-07-2003, 02:23 AM
According to what I've read, 20-25° is the most advance you would normally want. Too much advance causes overheating due to very high current draw. Putting my protractor on the screen shows that I am getting 15-18° of advance by twisting the commutator. Unfortunately, it is a bit more difficult to do it this way with as much precision as the 540 motors give with their adjustable endbells.

aperson
12-07-2003, 04:58 PM
is there anyway to retard the timing?

neurokinetik
12-07-2003, 05:06 PM
Yeah, turn the commutator the other direction. (Clockwise)

sherifx
12-07-2003, 05:27 PM
how are you pulling the tabs that hold the wires in, back?


sherif

TypeZer0
12-07-2003, 09:33 PM
do you mind putting up a couple pics showing how to properly take off the endbell? that woudl be really helpful

jaubery
12-07-2003, 10:45 PM
Great info. Thanks for posting. I just did it on a spare stage 1. I am anxious to see the results. Thanks again.

neurokinetik
12-08-2003, 08:05 AM
Originally posted by sherifx
how are you pulling the tabs that hold the wires in, back?


sherif

Not sure what you are asking here... are you talking about the tabs on the commutator that clamp the armature wires down?

sherifx
12-08-2003, 09:43 AM
thats exactly what I'm asking :D

sherif

neurokinetik
12-08-2003, 11:45 AM
Well, I haven't succesfully been able to pry them up, so I don't have the answer... :p I just solder the wire to the top of them instead.

sherifx
12-08-2003, 11:49 AM
lol, thats what I did :p !


sherif

TypeZer0
12-09-2003, 03:03 PM
no pics on how to take off the endbell? :( please? with sugar? and sprinkles? and a cherry on top? :D

neurokinetik
12-09-2003, 04:38 PM
I'll try to post them tonight... :p

TypeZer0
12-09-2003, 05:11 PM
thanks!! probably gonna tear apart either one of the stage 2 motors or my stock 1 motor as soon as i get the stage 2 kit.

neurokinetik
12-09-2003, 05:23 PM
OK, here you go... this is the important stuff, I'm assuming you already know how to pry the two tabs up on the side of the motor can.

Note the arrow. You will use a small flatblade here to pry the endbell off while leaving the brushes in place.

http://users.adelphia.net/~neurokinetik/dissassemble1.jpg

Gently twist...

http://users.adelphia.net/~neurokinetik/dissassemble2.jpg

Almost there...

http://users.adelphia.net/~neurokinetik/dissassemble3.jpg

Pulled off the endbell, note the brushes right where they belong.

http://users.adelphia.net/~neurokinetik/dissassemble4.jpg

Pivot the brushes out of the way, and you're sorted. Ready to swap magnets or advance timing.

http://users.adelphia.net/~neurokinetik/dissassemble5.jpg

TypeZer0
12-09-2003, 07:29 PM
thanks for the pics! :D i'm wondering, i remember someone saying that when they put their xspeed in their car, they had to reverse the polarity because xmods run motors backwards compared to most cars. according to the pictures in your first post, wouldn't that be retarding the timing or did you already take that into account?


oh yeah, since i got no big place to run my xmod, thanks to the big winter storm up here in boston, is there any other indication of improvement like sound?

neurokinetik
12-09-2003, 07:49 PM
Originally posted by TypeZer0
thanks for the pics! :D i'm wondering, i remember someone saying that when they put their xspeed in their car, they had to reverse the polarity because xmods run motors backwards compared to most cars. according to the pictures in your first post, wouldn't that be retarding the timing or did you already take that into account?


oh yeah, since i got no big place to run my xmod, thanks to the big winter storm up here in boston, is there any other indication of improvement like sound?

If you change the timing in the direction I show, it will be advanced when you are running it in an XMod. You will be able to hear the difference between a motor with advanced timing and one without. It will be revving higher.

TypeZer0
12-09-2003, 08:10 PM
ok cool. yeah, i did hear a difference in sound. damn, should've gotten another stock motor to compare it with, oh well. luckily i didn't break this motor hehe.

i didn't properly break in the motor but did run it below full throttle for a while. i was surprised by how well broken in one of the brushes were but the other brush...well, half of it looked good.....

joe_t1g
12-25-2003, 10:48 PM
Neuro, how do you swap magnets without taking it out of the can?

Plus... is it just me or is it tough to "gently twist" the timing? It seems stuck.

neurokinetik
12-26-2003, 12:28 AM
Swapping magnets without removing the armature is tricky, but it is doable. You have to pop the little spring clip loose on one side, then use a paperclip with a tiny hook bent on the end to pull the magnets out. Doing this with Neo magnets really sucks, as they usually go flying right back into the motor.

It isn't your imagination, the comm is actually "stuck". There are tiny little tabs on it that stick into the rotor and force it to neutral timing. When you twist, you actually break these little tabs off. After you are done, you can put a drop of superglue where the comm meets the rotor if you want to ensure that it doesn't move. It is much easier to adjust timing with the armature out of the motor, but it really is best to avoid pulling the pinion if you don't really have to. The easiest time to adjust timing is when winding a motor. You can just set it, glue the comm, and wind the motor with the timing already advanced.

red02zx3
12-27-2003, 10:51 AM
Neuro,

I would just like to know ......HOW DO YOU KNOW ALL THIS!!!:eek: :confused: What do yo do for a living? And, is there anyway you could show us all how to do FETs? Thanks for all the help on the boards! Keep up the amazing work!

neurokinetik
12-27-2003, 09:50 PM
Originally posted by red02zx3
Neuro,

I would just like to know ......HOW DO YOU KNOW ALL THIS!!!:eek: :confused: What do yo do for a living? And, is there anyway you could show us all how to do FETs? Thanks for all the help on the boards! Keep up the amazing work!

Well, let's see... Bachelor's degree in Electrical Engineering, 6 years experience working as a tech repairing consumer electronics, probably about 10 more years of misc electronics experience on top of that, and about five years of racing 1/10th and 1/12th scale R/C way back when I was a teenager.

Most of my motor knowledge draws upon my experience with the 540 motors in the 1/10th and 1/12th scale cars, and lots of trial and error...

red02zx3
12-28-2003, 06:14 AM
thats funny! I actually was going to shcool for electical engineering, and dropped it cause I thought it was too HARD! So now I repair and maintain jet engines....

Lucid Dreams
01-11-2004, 12:10 AM
ied love to see a pic of that pinion being pulled

red02zx3
01-12-2004, 06:05 AM
I have fought and fought with these stupid pinions and Im gonna tell ya right now....The BEST way to get that sucker off is to take a hand held propane torch(the ones you get at home depot for like 12 bucks) and heat it up till its glowing red. At that moment, use some needle nose pliers to just pop it off. When you heat it up that hot, it just FALLS off.

boxcrash
01-12-2004, 11:22 AM
Well I would say that heating it up is not a good idea at all.

The amount of heat generated from a propane torch to get a brass pinion glowing red would exceed the recommended maxium amount the internals of the motor and brushes could handle.

You can go to a slot car shop and get a pinion puller for about $8 usd.
They work great.

You can use a 2" C-Clamp from Home Depot to press them on with.

I cut the swivel foot off and drilled a recessed/concave area with a large drill bit in the stationary side and a air 90* angled drill.

red02zx3
01-12-2004, 01:59 PM
Ive done the propane torch thing at least 12 times and there have been ZERO problems with it. Of course I have the backshell off of the engine before I blow torch it.

boxcrash
01-13-2004, 12:01 PM
Well I was no trying to be jerk, just saying.

Better with the back of the motor off though. Probably fine, just saying that kind of heat is enough to change tempers of metal and might weaken the mags.

I just like to be careful thats all cause there is that chance, which I work on cars and I once heated a downpipe end so hot it glowed red and white because it was stuck and I killed the cat converter after getting it back together and driving it.
I mean you can tell me to shut up because I am probaly over reacting. Thats fine, was just my $.02 warning, thats all.:D

red02zx3
01-13-2004, 12:13 PM
There has to be skeptics, that is what makes us all stand back and think about things. Believe me, I didnt think it was a good idea either, till I tried it! And the pinion literally falls off.

Mr BigShot
01-13-2004, 12:14 PM
2" C clamp from home depot to install a pinion THANKS I've been using the heat with a torch and hit it with a hammer method " and I've wreak a few motor's " So thanks for the idea !!!

boxcrash
01-13-2004, 04:18 PM
Originally posted by Mr BigShot
2" C clamp from home depot to install a pinion THANKS I've been using the heat with a torch and hit it with a hammer method " and I've wreak a few motor's " So thanks for the idea !!!

Hey no problem, or you can use whatever C clamp works best,but I think it was the 2" I bought and use(the ones at the slot car are pretty mucha c-clamp anyhow). It will also work without cutting the swivel foot off. But when you use this on the 180's, be careful not to get to crazy cause it will try to push the shaft through the rear bushing cap. It never harmed a motor, the most it did once was put a little dimple/bump in the back where the shaft pressed, because the shaft does have some foward and back play.