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Old 09-26-2012, 07:58 AM
  #136  
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Originally Posted by rcwck
Definitely not gearing, you are geared for ~45mph, Voltron geared for ~60mph.
Your heat issue is somewhere else. A T8 esc should shut down(thermal) way before that temp of 240F. Mine thermals around 180 degreesF. Something is not right there.
Hope you're not using any software timing. These 1/8th heavy cars do not like much if any timing. That's one reason why Tekin T8's runs in dual mode(sensored to sensoreless)No Booost or Turbo to heat thing up.
Make sure the car coasts easily. Take off pinion/motor and give it a coast test. It should roll easily. All gear meshes should be smooth. Voltran's car is super smooth and quite. He goes 58mph on the straight.
I would guess with the T8 esc not thermalling is your problem source.
And yeh those YEH Racing 30x30 2S fans are money.

I'm getting somewhat interested in this car especially if Voltran gets any faster, lol. It's a little hard to get fired up now because our outdoor season just ended. I'd really like to see pivot ball suspensions front and rear which adds adjustability. Hopefully V2.
Desoto was untouchable at our big GLC race this year with his nitro version.
http://www.jlaprm.com/PC/Toledo/08_2...208th%20GT.HTM
^^^ Listen to What this Guy Says ^^^

Fastest on-Road driver i've seen, Dominates Electric Touring and GT8 at our track. He's all ways running fast as hell and his cars are always dialed.
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Old 09-26-2012, 08:20 AM
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Originally Posted by Voltron989
^^^ Listen to What this Guy Says ^^^

Fastest on-Road driver i've seen, Dominates Electric Touring and GT8 at our track. He's all ways running fast as hell and his cars are always dialed.
Very flattering, but you are new to onroad. Thinking you need some more tires or something, lol.

Just gonna contribute when I'm pretty sure I can help. I made plenty of goofs in my 40+ years of playing with rc. Gotta keep an eye on the competition.
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Old 09-26-2012, 08:30 AM
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I forgot to mention his mouth is as quick as his cars

Me and Leah goig to head down there in a lil while. Suppose to get sunny and 71. Hopefully it dries up by then.
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Old 09-26-2012, 09:36 AM
  #139  
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Originally Posted by rcwck
Definitely not gearing, you are geared for ~45mph, Voltron geared for ~60mph.
Your heat issue is somewhere else. A T8 esc should shut down(thermal) way before that temp of 240F. Mine thermals around 180 degreesF. Something is not right there.
Hope you're not using any software timing. These 1/8th heavy cars do not like much if any timing. That's one reason why Tekin T8's runs in dual mode(sensored to sensoreless)No Booost or Turbo to heat thing up.
Make sure the car coasts easily. Take off pinion/motor and give it a coast test. It should roll easily. All gear meshes should be smooth. Voltran's car is super smooth and quite. He goes 58mph on the straight.
I would guess with the T8 esc not thermalling is your problem source.
And yeh those YEH Racing 30x30 2S fans are money.

I'm getting somewhat interested in this car especially if Voltran gets any faster, lol. It's a little hard to get fired up now because our outdoor season just ended. I'd really like to see pivot ball suspensions front and rear which adds adjustability. Hopefully V2.
Desoto was untouchable at our big GLC race this year with his nitro version.
http://www.jlaprm.com/PC/Toledo/08_2...208th%20GT.HTM
Thanks for the help! I checked Hotwire and the Timing settings are 10 for timing advance and C2 for timing profile. Start RPM 5443, end RPM 20016. These are the factory settings I think, I know I have not changed them. I pulled the pinion and rolled the car. A good push and it rolls a couple feet. There is audible noise from the gears when I do this. Should it be silent or should there be some noise?
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Old 09-26-2012, 10:59 AM
  #140  
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Originally Posted by rcwck
Definitely not gearing, you are geared for ~45mph, Voltron geared for ~60mph.
Your heat issue is somewhere else. A T8 esc should shut down(thermal) way before that temp of 240F. Mine thermals around 180 degreesF. Something is not right there.
Hope you're not using any software timing. These 1/8th heavy cars do not like much if any timing. That's one reason why Tekin T8's runs in dual mode(sensored to sensoreless)No Booost or Turbo to heat thing up.
Make sure the car coasts easily. Take off pinion/motor and give it a coast test. It should roll easily. All gear meshes should be smooth. Voltran's car is super smooth and quite. He goes 58mph on the straight.
I would guess with the T8 esc not thermalling is your problem source.
And yeh those YEH Racing 30x30 2S fans are money.

I'm getting somewhat interested in this car especially if Voltran gets any faster, lol. It's a little hard to get fired up now because our outdoor season just ended. I'd really like to see pivot ball suspensions front and rear which adds adjustability. Hopefully V2.
Desoto was untouchable at our big GLC race this year with his nitro version.
http://www.jlaprm.com/PC/Toledo/08_2...208th%20GT.HTM
I just took it out for a run in front of my house. I ran it pretty hard for about 10 minutes. I checked the motor temp at the 10 min mark and I got an astounding reading of 259 degrees! Also it was far from silent. There is a pretty aggressive pitch to the sound when running wide open.
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Old 09-26-2012, 02:54 PM
  #141  
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hi Guys,
here a little test run of mine GT-E on the MACH track

Tekin 2650kv -4S

http://www.facebook.com/pages/The-Bo...4707639?ref=hl
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Old 09-26-2012, 05:07 PM
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Originally Posted by Bhodi11
I just took it out for a run in front of my house. I ran it pretty hard for about 10 minutes. I checked the motor temp at the 10 min mark and I got an astounding reading of 259 degrees! Also it was far from silent. There is a pretty aggressive pitch to the sound when running wide open.
What was the outside temp? 10 minutes is a long time to rip hard onroad depending on the temp. I still wouldn't think the motor would get that hot though.
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Old 09-26-2012, 05:39 PM
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Originally Posted by Voltron989
What was the outside temp? 10 minutes is a long time to rip hard onroad depending on the temp. I still wouldn't think the motor would get that hot though.
About 81, so not hot at all. Maybe it is the motor itself as it seemed to behave like the gears were slipping from time to time when it would start moving. It would almost stutter. It was different than the cogging I experience on my Castle setups. Sensor cable was in.

Never had this problem when motor was in the RC8.2e. Never got hot.

Just checked and my gear mesh has some slop. Motor mount is so tight on this thing it is had to gradually move the pinion in/out.
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Old 09-26-2012, 06:04 PM
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Originally Posted by Bhodi11
I just took it out for a run in front of my house. I ran it pretty hard for about 10 minutes. I checked the motor temp at the 10 min mark and I got an astounding reading of 259 degrees! Also it was far from silent. There is a pretty aggressive pitch to the sound when running wide open.
Look/listen to Border r/c video above. That sounds about right.

Thought we were talking about esc heating up? Is esc temp ok now?

Fan(s) should keep motor temp under control. Voltron has a good dual set up on his motor(pic posted). I have seen Tekin motors approaching 300. Motors will be short lived much above 180. Get some air flow also. I have 2 ducts from the windshield, one to the esc and one to the motor. Maybe some grill cut outs or brake ducts for the Snake just like the real race cars. These heavy cars really heat up things if you drive hard and use push brake. My esc will still thermal if I'm too hard on the brakes. Make sure zero or very little drag brake. Limit max braking in software or better yet at Tx braking end point. Using Tx end point allows you to dial in max brake on the track. I never have tires lock up under braking. My Kyosho GT2 conversion has mechanical brakes so no braking/heat issues there. Some have added mechanical brakes just for that reason.

Track temp also may require different gearing. When track temps are 130-150 I use a shorter gear.

I would zero out the timing. Doubt if you'd notice any performance change.

Are you sure your temp checker is accurate? I have seen those cheap ones way off. I have had some. Spit on finger placed on motor would instantly boil off at that temp. That's the method we used back in the day. Spit should slowly disappear.

10 minutes is way more than I can run hard using 6800 70C 4S lipos. Which tends to confirm your shorter gearing.

These cars can be frustrating about heat issues. I have had several heat issues and have spent hours/days sorting things out. I am lucky that I live very close to a great track where I can test. All members get a key.

Click on Aerial movie of track:
http://www.racersoftoledo.com/photo_gallery.html

Is this an offroad used motor? It is cleaned out with good bearings? Just a last thought.
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Old 09-26-2012, 06:22 PM
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Originally Posted by Bhodi11
About 81, so not hot at all. Maybe it is the motor itself as it seemed to behave like the gears were slipping from time to time when it would start moving. It would almost stutter. It was different than the cogging I experience on my Castle setups. Sensor cable was in.

Never had this problem when motor was in the RC8.2e. Never got hot.

Just checked and my gear mesh has some slop. Motor mount is so tight on this thing it is had to gradually move the pinion in/out.
Voltron had to do some custom work on his mount for the Tekin motor. Maybe he can chime in. Also most of my Tekin's sensor/bearing holder plate inside the motor come loose. I always remove the outer backplate and loctite the 3 button hd cap screws.
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Old 09-26-2012, 06:31 PM
  #146  
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Originally Posted by rcwck
Look/listen to Border r/c video above. That sounds about right.

Thought we were talking about esc heating up? Is esc temp ok now?

Fan(s) should keep motor temp under control. Voltron has a good dual set up on his motor(pic posted). I have seen Tekin motors approaching 300. Motors will be short lived much above 180. Get some air flow also. I have 2 ducts from the windshield, one to the esc and one to the motor. Maybe some grill cut outs or brake ducts for the Snake just like the real race cars. These heavy cars really heat up things if you drive hard and use push brake. My esc will still thermal if I'm too hard on the brakes. Make sure zero or very little drag brake. Limit max braking in software or better yet at Tx braking end point. Using Tx end point allows you to dial in max brake on the track. I never have tires lock up under braking. My Kyosho GT2 conversion has mechanical brakes so no braking/heat issues there. Some have added mechanical brakes just for that reason.

Track temp also may require different gearing. When track temps are 130-150 I use a shorter gear.

I would zero out the timing. Doubt if you'd notice any performance change.

Are you sure your temp checker is accurate? I have seen those cheap ones way off. I have had some. Spit on finger placed on motor would instantly boil off at that temp. That's the method we used back in the day. Spit should slowly disappear.

10 minutes is way more than I can run hard using 6800 70C 4S lipos. Which tends to confirm your shorter gearing.

These cars can be frustrating about heat issues. I have had several heat issues and have spent hours/days sorting things out. I am lucky that I live very close to a great track where I can test. All members get a key.

Click on Aerial movie of track:
http://www.racersoftoledo.com/photo_gallery.html

Is this an offroad used motor? It is cleaned out with good bearings? Just a last thought.
Thanks for the input. ESC has never shut off, it seems to be fine. The temp gun I have is a RYOBI from Home Depot. It was about $40.00 and seems fairly accurate. Dont think it would be off as much as we are talking here. The ESC was running around 130 - 140ish degrees. I agree this is pretty frustrating. I have not been back into the hobby for too long but I have a pretty steep learning curve when it comes to this kind of stuff. Could the motor just be under powered for the application? Does the crazy thick diff oil tax the motor more? It is 300,000 in front / center, and 40,000 in the rear. Is that a factor? I always thought the lower kv motors would run cooler and you could just gear up if you wanted to go faster. Does not seem to be the case here. I think I will do another test and run it about the same with the body off and see if that makes a huge difference.
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Old 09-26-2012, 06:40 PM
  #147  
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Originally Posted by border r/c
hi Guys,
here a little test run of mine GT-E on the MACH track

Tekin 2650kv -4S

http://www.facebook.com/pages/The-Bo...4707639?ref=hl
Nice video and awesome track!!! There is talk off one similar being built in my area. Hope it pans out. I would say my Cobra is a lot louder. But hard to say really. Lots of variables - mic in cell phones usually sucks, different motor and gearing, different body, etc...
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Old 09-26-2012, 11:07 PM
  #148  
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hi,
thanks,
i did use the plastic molded spur sound much better then the steel.
temp of the motor is around 85C top speed till now is 87 Km p/hour runtime around 14min.
next step is a other body then PF* i have my Lambo almost ready much lower and more steering show here a.s.a.p when i finished it,

esc just all the setting stock as it came in box no time too adjust it yet
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Old 09-27-2012, 03:47 AM
  #149  
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bhodi11 just curious what was the outside temp when you did your 10 min run?
And are you ripping up and down your street full throttle or are u at a track?
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Old 09-27-2012, 03:49 AM
  #150  
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Originally Posted by border r/c
hi,
thanks,
i did use the plastic molded spur sound much better then the steel.
temp of the motor is around 85C top speed till now is 87 Km p/hour runtime around 14min.
next step is a other body then PF* i have my Lambo almost ready much lower and more steering show here a.s.a.p when i finished it,

esc just all the setting stock as it came in box no time too adjust it yet
What gearing are you using?
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