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JasonC
11-20-2008, 07:19 PM
I just got a couple of motors, and I went to install one in my stadium truck, but I cannot mount it into the motor plate. The large end fits, but the whole for it to mount into the motor plate is a little too narrow.

It is a 550 size Traxxas Titan 12T, should I have gotten a 540 size?

What is 550/540 and the different sizes about, where is this measurement from?

Am I just unlucky and a lot of time 550 size motors will fit into vehicles that are made for 540s? I am asking because I bought two of these motors, one for the stadium truck and one for the HPI Sprint2 Drift that I just ordered, and now I am worried I won't have a motor for the truck when it comes in next week.

ecoli
11-20-2008, 07:28 PM
Even if you were able to get the motor to fit, it'll probably burn out in a couple of weeks. The Traxxas Titan's aren't really the best motors out there.

The biggest difference between the 550 and 540 motors is the length. 550's are definitely longer. However, I thought that the motor can diameter was the same for both? I know you can definitely run 540 motors on trannies built around 550 motors (i.e., the Traxxas XL-5 trannies), so the bolt patterns should be the same.

In any case, I'd still suggest taking the Traxxas motors back and replacing with something a little higher end. I think you'll end up disapointed with the Titan's based on mine, and a lot of others experience.

JasonC
11-20-2008, 07:40 PM
Even if you were able to get the motor to fit, it'll probably burn out in a couple of weeks. The Traxxas Titan's aren't really the best motors out there.

The biggest difference between the 550 and 540 motors is the length. 550's are definitely longer. However, I thought that the motor can diameter was the same for both? I know you can definitely run 540 motors on trannies built around 550 motors (i.e., the Traxxas XL-5 trannies), so the bolt patterns should be the same.

In any case, I'd still suggest taking the Traxxas motors back and replacing with something a little higher end. I think you'll end up disapointed with the Titan's based on mine, and a lot of others experience.
Thanks Chris, I got a great deal on the two brand new motors from another user here, so I am not going to worry about if I have them burn out.

Thanks for filling me in on the size thing....but the engine in the mini-t is a 350? or something like that and it is smaller diametre wise....no?

Tired
11-20-2008, 07:47 PM
The 540/550 measurement is generally can length in mm, as Ecoli mentioned, and yep, the smaller motors are 380, 370, or even smaller

The difference is that the Traxxas 550 12T cans from Rustlers, Stampedes and Slashes have a raised section around the shaft at the front of the motor that is slightly bigger than most 540s

JasonC
11-20-2008, 07:51 PM
Tired, do you know if it would hurt if I trimmed that raise section off of the can? All I really want is to not be stuck with a non operational car when it gets in, because I will be going nuts wanting to use it, so if I can trim these two motors and run them for even a day each I would be happy just to get the truck moving.

JasonC
11-20-2008, 09:00 PM
Also can someone explain to me what a 13 T double would be? I am just looking at other brushed motors that I might be interested in getting.

What do they call a stock motor and a spec motor as well?

I just want something with decent speed to get me going while I start out.

ecoli
11-21-2008, 07:58 AM
Probably easier to drill out the motor plate rather than trying to file down the motor can. Won't hurt it, whichever option you choose.

Definitely the mini-t uses a smaller diameter can. The 540 and 550 are just the standard sizes used for 1/10 vehicle transmissions with 540s being the most popular choice (and the ones with the most selection).

The number of turns a motor has represents the number of times the wire is wrapped around the armature. In general, the lower the turn motor, the faster the speed given the same gearing ratio in the tranny. Do make sure that your esc can handle the turn motor you're interested in. For example, if your esc is rated 15T, that means it can run 15T motors and higher. With a 13T motor, you risk damaging the esc. Even following that rule, you do need to make sure you gear things properly. Overgearing a motor (e.g., too large of a pinion gear) is a good way to get it to overheat and burn out.

As for stock and spec motors, the biggest difference is adjustability. A stock motor is often a closed endbell (i.e., you can't open it up or adjust timing), while spec of modified motors have adjustable timing, usually have bearings, and are completely rebuildable. Often these motors are handbuilt/handwound instead of machine wound. You can often get them in all sorts of winds with up to a quad strand. Hence, you pay a heftier price.

Finally, in terms of single vs double winds, it's probably what you think. A 13T double (or 13x2) means it's two wires wrapped 13 times around the armature. A single, well, you figure that one out :D! The singles give you more speed, less torque and vice versa for the doubles (for the same number of turns).

I would suggest sticking with something like the Trinity speedgems series in a single or double wound. Won't break the bank and will give you good speed. If you really want a maintence free system (pretty much), then I'd suggest going brushless. A 5700kv motor with a Sidewinder esc will give you lots of speed.

Good luck, the world of motors can be a confusing one :D!

dubfreak
11-21-2008, 08:30 AM
and when they say 7 turn in a cobalt is it the same thing cuz it would make a rather fast motor and less torkey motor but the cobalt puller 7t as lots of turn

frank