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Old 09-01-2003, 07:32 PM   #1
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Default Some problems

Seems like I always have problems, anyways I just got the ssg towers for my xxx-s from speedtech and they're awesome. Since my car was back together and the weather finally cleared up here near chicago (it drizzled for 2 days straight) I thought I'd take my car for a spin. Put some brand new 2400 batts in. When I turned it on it went crazy, I had to stop it with my foot then turn it off. I turned my radio on first too and I checked the crystals and everything. So I turned it back on and it was fine. I have no idea why it did this, could I have dirt in my reciever or something?

So I finally ran it and it only went maybe half as fast as it usually goes (like I could easily run faster than it). I checked my gear mesh, it was fine. I had a brand new fully charged battery in it so I didn't think that was the problem. I had just cleaned my motor about 3 runs ago. I have no idea what is wrong.

And to top it off some times I'll be running it and I'll come to a complete stop and then when i hit the throttle, nothing, it doesn't move. But the steering will still work. A guy suggested pulling back the brushes on the motor and lettting them "re-set" on the comm and it usually worked. But it didn't work at all this time.

I think my charger is half broken too. I have the super brain959. I usually charged my 1500's at 3 amps and at 10mv (still not sure what mv is, can someone clear that up?). They would peak at around 9.0volts. Now when I charge them they only peak at about 8.0volts.

If anybody can help me with any of my problems that would be awesome.


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Old 09-01-2003, 07:52 PM   #2
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What esc are u running??? U may have cooked an esc. Is that 10mv per cell or 10 mv perpack??? it should be 72mv per pack roughly for nicd's. I also charge at 6 amps. Check your motor for dirt and pebbles.
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Old 09-01-2003, 08:00 PM   #3
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Well first off did you have to reverse the motor on your raidio? that'll make it go slower.

Next when the car slows and wont move unless you push its a hung brush. file the edges of the brush because they get caught in the comm slots. that should solve that because i've done that before and that always fixes it. make shure the brush hoods are clean and push the brushes against the comm with a small screwdriver.

how often do you use your batts. if they've been sitting a while then they need to be cycled charge/discharge to get a little better voltage.

Oh yeah mv is millavolts thats usually used when the charger cuts off the charging when the battery is peaked.

Not bad for being only 14 huh
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Old 09-01-2003, 08:01 PM   #4
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I'm using the gm3 that came with it. I think I did cook it because I geared it at 5.75 one time and it got really hot fast. Actually i'm not sure if the 10mv is per cell or pack. I think it's pack, but I'm not sure.

That's not bad, i'm 14 too.
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Old 09-01-2003, 08:14 PM   #5
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10 mv a pack is way to low. i have 12 or 14 mv per cell on my mellenium pro. how long does it take to charge?

Iam from Benicia California and i race at Delta Rc California Raceway and with the good guys at R.O.C.K.S.

Just took home the west coast shootout 1st place trophy on monday. it took over 2 weeks for me them to get it to me.
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Old 09-01-2003, 08:51 PM   #6
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Firstly your motor need a comm cut and some new brushes, it's been run for more then 25 batt's right?

I run 2400's with 10mv's which is 60mv's overall. It works fine for me, I get 9.5v+ when my pack peaks. Some times I pull them off earlier if the v's start to go down(which I think means I should be running less mv's). How do you keep your pack in shape? that is probabely something to do with it.

After I run mine each week I take them home and cycle each pack twice at 6.0amps and 5mv cut off and 20amp dis with 30mins wait after dis and a 10 min wait after charge. Then I attach contineus dischargers that equalize the pack in about a week just ready for my next use. If I miss a week of racing I'll cycle them as I've noticed that I get bad performance from the first charge after a 2 week spell of being discharged.

No matter what you'll need new brushes, but if you don't have access to a comm lathe then you can try something I've been doing for a few weeks(each week after racing) with decient results(at your own risk). I 've been using 600 grit sandpaper to keep the comm smooth and clean. You wrap the sand paper around the comm completely and place three fingers(applying approximately the same pessure), one on each of the three faces of the comm. Then turn the armature in exactely three full revolutions smoothly then stop and take the snad paper off carefully as if you don't it could leave marks on the comm. If the comm is still dirty do the process again carefully. Then clean the motor fully install new brushes(if needed) and run-in the motor. *But* if you comm has a groove from the brushes wearing into it from too many runs it needs a comm cut, this can only be done with ok results on a smooth round comm.

Last edited by fatdoggy; 09-01-2003 at 09:03 PM.
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Old 09-02-2003, 05:39 AM   #7
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I think my comm has grooves in it. Plus I've noticed that it's harder to turn my motor by hand, like it's grity. I bet my motor and my batts are the problem. thanks guys.
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Old 09-02-2003, 04:50 PM   #8
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Put the armature in a drill with the commutator against the chuck. turn on the drill and see if it spins true. if it does get some 1000 or so grit sand paper and cut it into a small strip. polish your comm with just light pressure and its nice and clean. It gives you a fresh comm for cheap but it doesn't true it. make sure to clean out the armature slots with a knife and motor spray. take a ball point pen and push on the comm slots to round them down. This should help with the hung brush too. spray out your motor with motor spray also and a toothbursh to the brush hoods. re-oil your bushings and that should handle that.

If it doesn't spin true then try and align the chuck better with the shaft.
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Old 09-02-2003, 04:52 PM   #9
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u can also polish your armature shafts the same way so its supa smooth
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Old 09-03-2003, 11:01 AM   #10
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First things first, you said the pack was brand new, it won't really "come alive" for a few runs.

Second- find someone to rebuild your motor properly, or replace the armature and brushes with new parts.

Are you running the motor that came with the car?? if so just go and buy a new motor, from experience RTR motors usually only last from 10-20 battery packs, sometimes less, sometimes more, but mostly 10-20 runs.......
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Old 09-03-2003, 03:09 PM   #11
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Yeah its the losi xxx-s rtr, but it's hopped up a little but the electronics are all the same. I've had more than 20 runs with it so I'm thinking about just ditching my motor and getting a new one once I have the money. I dont want to deal with all that truing I'd probably screw it up more. Should I get a new esc too?
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Old 09-03-2003, 03:29 PM   #12
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If you gotta replace the motor, you'll most likely need to have a new ESC as well... most esc has a motor limited, say you should not use motor with less then 15 turns on some esc, or it'll fire out, or not response. for rtr esc, I think the motor limited will be quite tight..
but if you upgrade the speed, you'll need to upgrade the servo as well, or you may feel not be able to handle the car...
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Old 09-03-2003, 04:49 PM   #13
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I'm racing stock and my esc's motor limit is 15turns so I should be fine. Also doesn anyone know why my car just wont respond with my radio when I come to a stop sometimes?
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Old 09-03-2003, 07:19 PM   #14
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Quote:
Originally posted by zachzachz
I'm racing stock and my esc's motor limit is 15turns so I should be fine. Also doesn anyone know why my car just wont respond with my radio when I come to a stop sometimes?
you should get a new esc.. I had problems like that before and that fixed it ..car wouldn't respond and did run slow and i thought it was motor too. good luck...
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Old 09-03-2003, 07:30 PM   #15
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Default Too many problems

zachzachz;

Really as others have suggested. You should have your Motor rebuilt before you do anything else. Then if the problem is not solved, buy another ESC.
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