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Old 05-18-2008, 12:17 AM   #1
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Default Starter boxes and general info.

What turn of motors do most starter boxes use? 55-turn, 47-turn, 27-turn? I have no idea. I know it's as simple as just buying some motors for starter boxes and putting them in. But I'd like to know more about what is generally used.

Suggestion; I can't recommend using two 7.4 Lipo packs in your starter box. There is too much juice from the batts for these motors to withstand. The box will work great for a while. Here's the thing. Whe a 7.4 lipo is freshly charged the voltage is close to 8.4v. When two packs are used simultaneously (in series, I think) the voltage is over 16v. I was using two Maxamps 7.4 batteries. When the C rating is figured in, the amperage put out by the batteries is 120amps. Yikes! Looking at the 14.8v 20c batteries designed for starter boxes, their amperage is waaay down at 40 amps (this is figured with a 2000mah 20c battery; a common size starter box lipo.)

Long story short--I've been burning up starter box motors about once a weekend. I have a normal 14.8v 20c lipo now. So I don't need to worry about too much juice. I'm just looking for general info about the workings of starter boxes in general. Post your comments.
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Last edited by air8; 05-18-2008 at 07:38 PM.
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Old 05-18-2008, 03:38 AM   #2
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What turn of motors do most starter boxes use? 55-turn, 47-turn, 27-turn? I have no idea. I know it's as simple as just buying some motors for starter boxes and putting them in. But I'd like to know more about what is generally used.

Suggestion; I can't recommend using two 7.4 Lipo packs in your starter box. There is too much juice from the batts for these motors to withstand. The box will work great for a while. Here's the thing. Whe a 7.4 lipo is freshly charged the voltage is close to 8.4v. When two packs are used simultaneously (in series, I think) the voltage is over 16v. I was using two Maxamps 7.4 batteries. When the C rating is figured in, the amperage put out by the batteries is 120amps. Yikes! Looking at the 14.8v 20c batteries designed for starter boxes, their amperage is waaay down at 40 amps (this is figured with a 2000mah 20c battery.)

Long story short--I've been burning up starter box motors about once a weekend. I have a normal 14.8v 20c lipo now. So I don't need to worry about too much juice. I'm just looking for general info about the workings of starter boxes in general. Post your comments.
Was having trouble with my starter box guess this info helps.Anyway going to convert all to nimh bateries.
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Old 05-18-2008, 01:52 PM   #3
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Cool starter box

i have a mugen starter box with 1 4800 mah li-po 7.4 volts battery ,i replaced the 2 stock 27 turn motors with 2 55 turn motors ,and i havent had any problems since this will turn over the meanest motors with no problem without heating up the motor, .i just saw that a r/c car magazine just did an article on the starter box tune up and this is what they did check it out ...
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Old 05-18-2008, 02:25 PM   #4
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Any of the older starter boxes with the dual 550 motors can turn over many engines. You need amps to get real power to turn over the motor so that is where the 12v gel cell 7amp box comes into play. Nowadays they come with a 775 single or dual motor setup. Just make sure the rubber wheel is hitting the flywheel and not against the chassis causing you to put stress on the motors and wearing out the rubber wheel.
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Old 05-18-2008, 07:38 PM   #5
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Viper--I read that same article last month. It's kind of what got me thinking about what turn the motors are that starter boxes use.


I didn't know if 55-turn motors would spin fast enough. And this is another reason I decided to start asking questions. I'm sure the 55's would have the torque, but would they spin fast enough? I have some powerful 27-turn motors lying around from before the brushless days, and I could use them if they have the torque. So, IDK. I thought about ordering the 775 Ofna motors, and I know I'd be covered there. So anyone know what turn those 775 motors are? Like 55-turn, or something?
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Old 05-18-2008, 08:17 PM   #6
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I don't think that Stock 540's would cut it. Maybe something like Traxxas Titan 550 Motors?
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Old 05-18-2008, 08:25 PM   #7
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I have the mugen starter box 2. I has the stock motors (not sure what size) I think to 550's............... I use two 7 cell nimh and this box is awesome. 14 cells is the way to go if not using lipo
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Old 05-18-2008, 09:00 PM   #8
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You don't need speed to crank the motors over you need TORQUE. The power comes from the higher amperage that a 12v gel cell provides. The higher the volts the more rpm, but the higher the amps the more torque/driving force you'd have to crank over an engine. The 775 motors are pretty good. I have the univeral box (silver single 775 motor) and it will crank over plenty of engines. It also works with 10th and 8th vehicles.
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Old 05-18-2008, 10:04 PM   #9
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I think the amperage is my problem. I'm using my two Maxamp lipos from the 10th scale vehicles. They are 6,ooomah 7.4v a piece. I believe the amps they put out is around 120amps per battery. But they are wired in series so both of them together put out 120 instead of 240. And here is the problem--the motors keep burning up. When I used the Nimh cells I never seemed to have a problem. But two 4600 Nimh matched packs don't put out the juice that the 6ooo lipos put out. I think I'm actually over amping the motors.

Since I now have a 2100mah 14.8 lipo, I think I'll try the Titan motors from Traxxas. but just cause they are like $12 or something. Cause the new battery should only be putting out 42 amps at best---not 120amps.

Idk. I'll post back next week about how things go.
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Old 05-18-2008, 11:01 PM   #10
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Woah you don't need that much amps!!!!! All you need is 7amps of power to crank over these RC engines. A single or dual 775 motor box with a 7-7.5amp battery is all you need. Dual stick packs are more than enough to crank over a motor as well. A pair of 4600NIMH packs should be more than enough.
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Old 05-19-2008, 01:41 AM   #11
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LOL. Yea, I know I don't need that much. I setup this way so I could start three vehicles plus whoever else's vehicles all day long with no dead batteries. That was my intention anyways. Like when someone comes over to you at the races and says, "hey man, would you let me and my buddy start our cars on your box? Our's is dead." And then they have burned glow plugs with out knowing it. Or a dead igniter. They just keep trying, and trying, and trying to start the vehicle. Now, I'm more than willing to help someone get there vehicle going. But if it prevents me from starting MY vehicle come A-main time, then I don't want to help others ALL DAY LONG.

So that's why I set my box up with two 7.4, 6K lipos. I haven't needed to start many other vehicles besides my own so far. Anyways, I just wanted to do some shopping for new motors, but wanted info as to what turn the 550 and 775 motors are. Cause if they're 27 turn motors, I have many of those. But if they're a higher turn, I'll need to start shopping.
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Old 05-19-2008, 05:12 AM   #12
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my ae box starts my cars allday long.. i just use standard 2-3000 nimh batteries.. i had 4300 hundreds in it and was suprised they had less power than the 3000.
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Old 05-19-2008, 07:17 AM   #13
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I use a BMW motorcycle battery in my ofna starter box. It only has one 550 motor and it will still crank over my high compression engine very well.
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Old 05-19-2008, 01:55 PM   #14
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Why Why Why?

Ofna Chrome Top with a 12v gel cell and never look back.

I have used a "used" chrome top for about 3 years now and have had zero issues. I have started the most stuborn of engines with it, P5, RB's, Vspec's. All without any real trouble. Once a motor is run in I dont even have to charge the thing each week. Just this weekend I raced and used the box with a 3 week old charge. Starts my motor right up everytime.

If your gonna say its heavy, blah blah blah , are you running around the track with the thing? My box comes out of my truck on the table and is there all day.

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Old 05-19-2008, 04:21 PM   #15
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Why Why Why?

Ofna Chrome Top with a 12v gel cell and never look back.

I have used a "used" chrome top for about 3 years now and have had zero issues. I have started the most stuborn of engines with it, P5, RB's, Vspec's. All without any real trouble. Once a motor is run in I dont even have to charge the thing each week. Just this weekend I raced and used the box with a 3 week old charge. Starts my motor right up everytime.

If your gonna say its heavy, blah blah blah , are you running around the track with the thing? My box comes out of my truck on the table and is there all day.

I hated using the gel cell batteries. I gave all mine away and will never return to them. But thats just my opinion.
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