Drive train always broken on Circuit 2WD

Oldgameguy

Oldgameguy

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Orlando Florida
Something in the drive train is constantly broken on both my Circuit 2WD trucks with upgraded brushless motors. With the original plastic drive shafts there were two points of failure. The first point of failure was at the axle that connects to the wheel. The parts have a plastic part that connects to the metal axle and those would spin independently. I blew through three sets of those rear axles. The hobby shop owner showed me how to super glue the parts back together but that hasn't worked. The second point of failure was the U joints where the plastic part of the drive shaft connects to the motor. I bought many of those and they keep breaking. So I read the forums and chose the hot racing metal drive shafts. But after just a few minutes of use the aluminum wheel nuts have stripped the plastic hex shape of the wheel. The wheels have been ruined.

I followed instructions for the slipper clutch and set it tight but then back two turns.

Any help is appreciated.
Scott
 
Oldgameguy said:
Something in the drive train is constantly broken on both my Circuit 2WD trucks with upgraded brushless motors. With the original plastic drive shafts there were two points of failure. The first point of failure was at the axle that connects to the wheel. The parts have a plastic part that connects to the metal axle and those would spin independently. I blew through three sets of those rear axles. The hobby shop owner showed me how to super glue the parts back together but that hasn't worked. The second point of failure was the U joints where the plastic part of the drive shaft connects to the motor. I bought many of those and they keep breaking. So I read the forums and chose the hot racing metal drive shafts. But after just a few minutes of use the aluminum wheel nuts have stripped the plastic hex shape of the wheel. The wheels have been ruined.

I followed instructions for the slipper clutch and set it tight but then back two turns.

Any help is appreciated.
Scott
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Try turning the punch down on your esc.
 
Thanks for the reply.

I can figure out how to program the ESC but if that is the problem then the standard ESC settings are such that the drive train rips itself apart on both cars. My assumption is that the drive trains should not fail after five minutes of normal use. I drive the cars around in laps around my front yard made of cut grass. Occasionally I hit my mailbox or get some air but it is the drive train that breaks, not the parts that impact. I do not slam the throttle or slam it into reverse. So either the drive trains are breaking for everyone with a brushless motor or it is user error with driving or the slipper clutch or something.
 
I found a video on how to adjust your slipper clutch (
) and tried to replicate it. No matter how I turned the slipper screw it didn't affect the spinning of the wheels. Disassembly showed that the slipper clutch plates were fused together. So effectively I didn't have a slipper clutch. I pried the pieces apart and cleaned them off. The exploded view of the parts in the back of the ECX Circuit manual showed how many parts were supposed to be separate. Then I followed the rest of the video to set the slipper clutch screw. This fixed the problem and my truck was back in business.
 
Well, you're right that the drivetrain shouldn't fail so frequently and thoroughly. What type of motor do you have? (in turns or kv) It sounds like it's too powerful for the car. Especially since it's overwhelming the slipper clutch plates.

I used to race my Circuit on indoor carpet with a 13.5T brushless system, stock plastic transmission and even a plastic pinion gear (26T) with a 76T Associated spur. High traction surface, high speeds, and totally unforgiving walls, jump edges, bricks, etc. Never damaged the drivetrain. Granted, a 13.5T brushless motor isn't the definition of hot being the equivalent of 2800kv when most "basher upgrade" brushless motors seem to start at 3000/3500kv.

One option would be to replace the ECX driveshafts with modified Traxxas VXL driveshafts. See the stickied thread at the top of this forum.

As for setting the clutch: the "two turns from locked" is just a starting point. You need to adjust tighter or looser based on driving conditions, traction, etc. You may have even seen it on YouTube, but a good way to set your slipper (on a 2WD car) is to put your car on the ground/work bench, hold the right rear tire with your your right hand and plonk the base of your radio on the left. Punch the throttle. How much does the front of the car lift off the surface? Not at all, with lots of buzzing? Then the slipper is too loose. Pop a wheelie? Too tight. Lifts up just a little? Pretty much just right. Then tighten a bit for higher traction surfaces and loosen a bit for lower traction surfaces.
 
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I broke a drive shaft on my 15t brushed setup. The reason for it being that is was like 5°c out. Don't drive with plastic parts in the cold.
 
I use Traxxas Slash 4x4 driveshafts. You just need to drill out the part that connects to the diff outdrive. In almost 4 years of constant abuse, I've only broken two drive shafts with a 3300 KV motor
 
Traxxas 6852x driveshafts are what you need. Need a little modification to get em on but that's what solved my drivetrain issues.
 
I've done the Traxxas driveshaft mod and find them to have the same durability as the stock ones at least on 3s on a 3100kv 3665 can 1/8 buggy motor. They are much cheaper though, I think I can get 2 sets of the Traxxas ones for the same price as the Ecx.
I think I'm going to break down and buy a set of the new Hot Racing driveshafts. http://hot-racing.com/?partnumber=SECT288RC;c=685
 
I've used the hotracing aluminum driveshafts, the good ones not the shitty dog bones, there a waste of money. Perhaps your problem is your running a 1/8 motor in a 1/10 vehicle and using components that weren't designed to run on 3s with that type of motor. If you put a Ferrari motor in a ford focus bad things are going to happen...
 
Music411 said:
I've used the hotracing aluminum driveshafts, the good ones not the shitty dog bones, there a waste of money. Perhaps your problem is your running a 1/8 motor in a 1/10 vehicle and using components that weren't designed to run on 3s with that type of motor. If you put a Ferrari motor in a ford focus bad things are going to happen...
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Exactly. Driving my truck on 3S is how I broke the only two driveshafts on my truck. I've broking absolutely zero on 2s.
 
MaX-D said:
Exactly. Driving my truck on 3S is how I broke the only two driveshafts on my truck. I've broking absolutely zero on 2s.
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So... why don't you just rock with 2s... I swapped motors but before I did I had a buggy that would do a steady 40mph on 2s... I just don't get why people run 3s lol...3s always in a 1/10th always means broken parts.
 
Music411 said:
I've used the hotracing aluminum driveshafts, the good ones not the shitty dog bones, there a waste of money. Perhaps your problem is your running a 1/8 motor in a 1/10 vehicle and using components that weren't designed to run on 3s with that type of motor. If you put a Ferrari motor in a ford focus bad things are going to happen...
Click to expand...
I tried running the 3800kv Castle Sidewinder SCT esc motor combo and even on the smallest pinion I could fit it still ran stupid hot and burned out the motor. With that 3665 can motor it runs super cool with an 18t pinion. I think if I geared down and ran a higher kv motor it would be better 3100kv is a lot of torque for those driveshafts, even on 2s it starts to wear out the plastic at the u joints.
 
slick2500 said:
I tried running the 3800kv Castle Sidewinder SCT esc motor combo and even on the smallest pinion I could fit it still ran stupid hot and burned out the motor. With that 3665 can motor it runs super cool with an 18t pinion. I think if I geared down and ran a higher kv motor it would be better 3100kv is a lot of torque for those driveshafts, even on 2s it starts to wear out the plastic at the u joints.
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Well 3s may be fun.. but you gotta pay to play that game lol..
All I can say is I run my circuit on the same system (castle sct 3800 sidewinder 3) have it geared 20/87 and have no issues at all. Metal gear tranny set and traxxas driveshafts. Havnt had a drivetrain issue in over a year. Get a top speed around 30mph. I've tried those exact driveshafts your looking at and trust me, there no good.. I broke 2 parts on them, same part twice so after replacing it twice I just trashed em. There not more durable as the metal is cheap and breaks under stress whereas plastic flexes.. many people will back that fact up if you ask around. I don' know how your driving your truck or how your slipper is set.. but somethings wrong
 
Music411 said:
Well 3s may be fun.. but you gotta pay to play that game lol..
All I can say is I run my circuit on the same system (castle sct 3800 sidewinder 3) have it geared 20/87 and have no issues at all. Metal gear tranny set and traxxas driveshafts. Havnt had a drivetrain issue in over a year. Get a top speed around 30mph. I've tried those exact driveshafts your looking at and trust me, there no good.. I broke 2 parts on them, same part twice so after replacing it twice I just trashed em. There not more durable as the metal is cheap and breaks under stress whereas plastic flexes.. many people will back that fact up if you ask around. I don' know how your driving your truck or how your slipper is set.. but somethings wrong
Click to expand...
Did I mention I have a Ruckus? Bigger tires = harder on the drivetrain.
Well cripes, it seems like none of the Hot Racing driveshafts are worth a damn. I'll just break down and get the MIPs.
 

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