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Losi SCTE electronics issue

Losi SCTE electronics issue

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Old 06-16-2011, 12:53 PM
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Default Losi SCTE electronics issue

I have a TEN-SCTE, Love the truck, my problems are electrical.
I was running a MMP with a Ballistic 550 4.5, I was having alot of stuttering problems and sometimes the MMP would like reset itslef, truck would sit there motionless, then you would see the front wheels twitch and center and it would work again for a little while. I put an old GTB in and that worked for a couple heat races then the Neg. lead to the battery kept unsoldering from the deans plug about the 2 to 2 1/2 minute mark. I called novak they said it was either the timing sensor board in the motor (I didn't think it was because it happened with a fantom fusion 5.5 as well) or a fet on the GTB. They sent me a sensor board and that did't fix it so I bought a new Havoc pro sc speedo. That worked for my first heat last weekend then about 2 minutes into the second heat the Pos. terminal on my battery ( venom 40c 5000mah) melted off the battery, or I should say out of the battery. I talked to alot of guys at the track they all thought it was the battery, I wasn't sure but I ran the main anyway, I ran a 65c 5600MAH pack ($130) in the main and same thing, melted the banana plug right out of the battery 2 1/2 minutes into the race. I was geared at a 15/40 with a Fantom Fusion2 550 6.5 motor. The motor and speed control were warm but not burning up, I held my hand on the motor to check it i would guess it was barely 120. I took the diffs out when I got home and they feel smooth, no binding, wheel bearings are smooth. I guess my question is do you have any idea what I can check. The track I run on is pretty much wide open, I touch the brakes maybe once a lap if that, I am on full throttle for most of it with a couple of spots where I am on and off. I love the truck but I am very frustrated with this. If you have any thoughts on this please let me know.
I have Chris pins in the diffs and I am running 3000 front, 3000 center, 2000 rear for fluids, I have it pretty much on Caspers stock setup on losi's site.
I asked Casper this question and he thought it may be the banana connector not being efficient enough. I am getting mixed reviews from others on this including a guy from Fantom that my LHS talked to.
Any help or ideas would be greatly appreciated.
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Old 06-16-2011, 01:07 PM
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Originally Posted by WIGMAN View Post
I have a TEN-SCTE, Love the truck, my problems are electrical.
I was running a MMP with a Ballistic 550 4.5, I was having alot of stuttering problems and sometimes the MMP would like reset itslef, truck would sit there motionless, then you would see the front wheels twitch and center and it would work again for a little while. I put an old GTB in and that worked for a couple heat races then the Neg. lead to the battery kept unsoldering from the deans plug about the 2 to 2 1/2 minute mark. I called novak they said it was either the timing sensor board in the motor (I didn't think it was because it happened with a fantom fusion 5.5 as well) or a fet on the GTB. They sent me a sensor board and that did't fix it so I bought a new Havoc pro sc speedo. That worked for my first heat last weekend then about 2 minutes into the second heat the Pos. terminal on my battery ( venom 40c 5000mah) melted off the battery, or I should say out of the battery. I talked to alot of guys at the track they all thought it was the battery, I wasn't sure but I ran the main anyway, I ran a 65c 5600MAH pack ($130) in the main and same thing, melted the banana plug right out of the battery 2 1/2 minutes into the race. I was geared at a 15/40 with a Fantom Fusion2 550 6.5 motor. The motor and speed control were warm but not burning up, I held my hand on the motor to check it i would guess it was barely 120. I took the diffs out when I got home and they feel smooth, no binding, wheel bearings are smooth. I guess my question is do you have any idea what I can check. The track I run on is pretty much wide open, I touch the brakes maybe once a lap if that, I am on full throttle for most of it with a couple of spots where I am on and off. I love the truck but I am very frustrated with this. If you have any thoughts on this please let me know.
I have Chris pins in the diffs and I am running 3000 front, 3000 center, 2000 rear for fluids, I have it pretty much on Caspers stock setup on losi's site.
I asked Casper this question and he thought it may be the banana connector not being efficient enough. I am getting mixed reviews from others on this including a guy from Fantom that my LHS talked to.
Any help or ideas would be greatly appreciated.
Your fix is simple.. put the MMp back in and use a bypass or external BEC. The bypass is ONLY if you are running a 2s lipo setup all the time, it will fry everything if you plug in a 3s lipo or more. To do a bypass simply jump power from your lipo directly into your Rx. BEC is basically the same thing but allows use of any voltage lipo that it is rated for. WITH BOTH OPTIONS, you will want to disable the onboard bec, this is done by simply removing the center wire on the ESC plug that goes into your Rx. I tell most to get a small extension wire and just cut the center wire on the extension so you don't have to plug it back and forth in/out when you want to program the ESC.

The onboard bec on the mmp is junk, this is what causes most issues you describe.
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Old 06-16-2011, 01:18 PM
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Can you use a Y connector to plug the BEC and the esc into one channel on the receiver? so long as the side of the esc the red wire is disabled somehow?
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Old 06-16-2011, 01:34 PM
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I tried a castle BEC, It did not help, with the cogging or the MMP seemingly reseting itself. Works fine in my 2wd with a 17.5 but could not get it to work with the Ballistic 4.5 or a friends Fantom Fusion2 5.5. Thats why I tried the GTB and it worked fine till the Neg lead to the battery unsoldered from the deans plug.
With the Havoc Pro SC I plugged the esc directly into the battery, no deans connector just a banana style plug on the end of the esc wire. I guess I am curious if a better quality banana style plug will fix the issue of the plug melting pout of the battery in 2 1/2 minutes.
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Old 06-16-2011, 01:41 PM
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Originally Posted by Moogumby View Post
Can you use a Y connector to plug the BEC and the esc into one channel on the receiver? so long as the side of the esc the red wire is disabled somehow?
Yes
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Old 06-16-2011, 01:41 PM
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Originally Posted by 8ight-e View Post
Your fix is simple.. put the MMp back in and use a bypass or external BEC. The bypass is ONLY if you are running a 2s lipo setup all the time, it will fry everything if you plug in a 3s lipo or more. To do a bypass simply jump power from your lipo directly into your Rx. BEC is basically the same thing but allows use of any voltage lipo that it is rated for. WITH BOTH OPTIONS, you will want to disable the onboard bec, this is done by simply removing the center wire on the ESC plug that goes into your Rx. I tell most to get a small extension wire and just cut the center wire on the extension so you don't have to plug it back and forth in/out when you want to program the ESC.

The onboard bec on the mmp is junk, this is what causes most issues you describe.
The BEC won't cause the unsoldering, thats clearly an amp draw issue.
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Old 06-16-2011, 01:44 PM
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Originally Posted by WIGMAN View Post
I tried a castle BEC, It did not help, with the cogging or the MMP seemingly reseting itself. Works fine in my 2wd with a 17.5 but could not get it to work with the Ballistic 4.5 or a friends Fantom Fusion2 5.5. Thats why I tried the GTB and it worked fine till the Neg lead to the battery unsoldered from the deans plug.
With the Havoc Pro SC I plugged the esc directly into the battery, no deans connector just a banana style plug on the end of the esc wire. I guess I am curious if a better quality banana style plug will fix the issue of the plug melting pout of the battery in 2 1/2 minutes.
You are drawing too many amps, thats whats causing your unsoldering and melting issues.

First thing I would do is go down 2 teeth on the pinion gear. 15/40 is too tall a gear for the 4.5 if you have a heavy finger like you describe

If you are still having the same issues after gearing down, I'd borrow a different motor and see if there isn't an issue with your current one. Same with the ESC.
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Old 06-16-2011, 01:48 PM
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Originally Posted by Ridley View Post
The BEC won't cause the unsoldering, thats clearly an amp draw issue.
He stated that there were only heat issues w/ the novak.. but your right if there is the same heat issues w/ both ESC's I agree. The symptoms noted in reguards to the mmp were typical for the BEC issue. He could have more than one thing going on...
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Old 06-16-2011, 01:58 PM
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Originally Posted by 8ight-e View Post
He stated that there were only heat issues w/ the novak.. but your right if there is the same heat issues w/ both ESC's I agree. The symptoms noted in reguards to the mmp were typical for the BEC issue. He could have more than one thing going on...
I jumped on the reading comprehension failboat evidently

Went back and reread the post, and 8ight-E is 100% right, and thats what I'd do first along with gearing down, put the MMP back in and run direct power from the battery and disconnect the red wire from the ESC to RX plug.

If it still stutters, cut the switch off and solder the wires together, the castle switches suck

If you still melt batteries, there must be a motor issue or binding somewhere else.

Also check your servo endpoints, binding of the servo can cause all sorts of feedback issues.
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Old 06-16-2011, 01:59 PM
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I ran a Novak 4.5 550 w/MMP geared @ 40/16 on 2s 2 weeks ago in my LOSI-SCTE weighing in @ 7lbs 14oz. (before my carbon chassis) and had no problems all day whatsoever.
If the 4.5 and MMP couldn't handle the high current draw, I would have seen it first hand.
I don't have any fans on my motors and my fan on the MMP never came on that day.
I was using 6.5mm bullets from CC and 2x ThunderPower 65c 5300mah 2s in parallel for the main and 2x Enerlands 45c 4500mah 2s in parallel for the heats.
I also use CC 10 gauge wire on the motor and reduced the timing on the endbell to 15* and no timing on the esc and high power start which is another big help in cogging issues in my experience.
I also use a CC BEC just for the servo and use the BEC inside the MMP for the transponder and radio and all servo EPA are set correctly.
+1000 on getting rid of the switch on the MMP, it is one of the first things I do to any CC's ESC's.

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Old 06-16-2011, 02:00 PM
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I could not run with the MMP, the desoldering happened with the GTB and the Havoc Pro SC, The gtb was run with the ballistic 4.5 and a fantom 5.5, the Havoc happened with a fantom 6.5, could not try the ballistic 4.5, it was having what turned out to be timing issues from my circuit board swap.

If it was an over gearing thing would the motor not be burning up hot? Reason I ask is because thats the first thing I checked and it was not hot.
I see your point about amp draw though, I just figured overgearing would heat the motor up first.
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Old 06-16-2011, 02:54 PM
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Mmpro will handle an 1/8 scale buggy so that shouldn't be your problem. Try putting it back in and running with an external bec. I wouldn't run without one unless your servo is hv. Also try disconnecting the sensor wire and see if it still acts up. If you aren't using good bullet connectors they will also be an issue. U need the solid ones like protek or castle makes. Overgearing usually makes the esc run hot, undergearing makes the motor run hot. With a 6.5 I would think u should be up around a 19-20 tooth pinion. With the 4.5 ballistic you should be around a 13 tooth pinion.

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Old 06-16-2011, 03:43 PM
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Originally Posted by WIGMAN View Post
I see your point about amp draw though, I just figured overgearing would heat the motor up first.
Not at 2 1/2 minutes. It can cause certain areas of the current transfer to heat up much faster where you wouldn't feel it at the motor.

We can't run 4.5's on anything higher than a 13t pinion without melting down here. It has a lot to do with how heavy your finger is on the throttle and the surface of your track. We've had stuff desolder as well, and gearing down was the fix. However, like 8ight-e said, you may have multiple issues.

Of the guys here that tried any novak esc's...none were able to get them to work long term reliably.

Also, most of the guys here that tried to use MMP's, most have got rid of those as well. Shoddy quality, need bandaid fixes, and then still have cogging issues for no apparent reasons...

My best advice is to get a Tekin RX8, and send your motor in to have it looked at. You shouldn't have any issues with those products from then on out.
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Old 06-16-2011, 06:28 PM
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Thanks for all the advice guys, I was leaning toward an RX8, wish I would have saw that stormer had them for $178 when I got my Havoc pro Sc. I see alt of the Losi guys running the Novak stuff and figure if it works for them. I will admit to the heavy trigger finger on this track, they made it for 1/8 scales but we have more 1/10 scales that run. It is pretty much wide open in the 4x4, It takes 35-40 seconds to get around the track and I would guess I am at full throttle for about 25 seconds (not all at once obviously), longest burst is probably 6 seconds down the back straight. It is a very fun track with some big air. the associateds are actually adding weight cuz they get blown around on the big jumps, my losi flys like a bird over them.
Once again thanks everyone, I may put my MMP back in and put the havoc in my 2wd and see what happens.
So frusterating.
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Old 06-16-2011, 06:53 PM
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Originally Posted by WIGMAN View Post
Thanks for all the advice guys, I was leaning toward an RX8, wish I would have saw that stormer had them for $178 when I got my Havoc pro Sc. I see alt of the Losi guys running the Novak stuff and figure if it works for them. I will admit to the heavy trigger finger on this track, they made it for 1/8 scales but we have more 1/10 scales that run. It is pretty much wide open in the 4x4, It takes 35-40 seconds to get around the track and I would guess I am at full throttle for about 25 seconds (not all at once obviously), longest burst is probably 6 seconds down the back straight. It is a very fun track with some big air. the associateds are actually adding weight cuz they get blown around on the big jumps, my losi flys like a bird over them.
Once again thanks everyone, I may put my MMP back in and put the havoc in my 2wd and see what happens.
So frusterating.
Many of us also run the MMP with no issues. It's a weird deal in your case. Hope you get it worked out..sorry can't offer anything different
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