Tekin ROC412 motors

[JMiller2065]

I was thinking about dropping in one of the new ROC412 motors and the new GEN 2 Teken esc in my LCC. I currently run brushed (FXR and handwound motors on 2S) and have so for over a year now with no problems. I just read that everyone says brushless is the way to go on the LCC so I wanted to try it, but I'm curious if anyone has tried these motors and what KV would anyone suggest on this motor.

[WAM]

A friend and myself both have them in LNCs. He's happy with his, me not so much. Mine stutters badly on steep slow downhills. I can minimize that by using very small pinions but then wheelspeed is poor. I counter that by running the 3100kv on 3S. It's okay, but not what I was hoping for. When my sensored esc started acting up, I went back to brushed and am much happier.

[JMiller2065]

Thanks for the info. I love the feel of brushed motors and by the sound of your experience may be an expensive dissappointment if i try it.

[WAM]

Or it might work fine for you. It's a very capable motor. But the combination of worm gear drag and very slow speeds may be a problem. Search Grimjeeper91's posts for his take on the motor. He's much happier with it than I am.

[Olle P]

I have no experience with the ROC412 as such, but here's my take:
- BL is the way to go if you want [b]speed].
- Brushed motors are better for the very slow crawling parts of a run. Period. They can easily overheat if you try to make them go fast as well though.
- I'm not sure which BL motor gives you the smoothest low end, a low Kv (with a high voltage battery) or high Kv (3100).

My motor (Kv 1870 with 15 degrees mechanical timing) needs a 12T pinion to run sufficiently smooth at the low end.

[irok]

I have the 2300kv in mine and i'm also not impressed with low speed control.I'm running a 13t pinion but usually try to use a 12t but had trouble getting the backlash close enough.
It's ok but was expecting more outa it after all the hype.
My novak 17.5 was just as smooth using the same RS esc,on 3s power.
I may try a brushed setup as well,,maybe a Homles TM Pro 13t.

[dentonmac]

Originally Posted by WAM

A friend and myself both have them in LNCs. He's happy with his, me not so much. Mine stutters badly on steep slow downhills. I can minimize that by using very small pinions but then wheelspeed is poor. I counter that by running the 3100kv on 3S. It's okay, but not what I was hoping for. When my sensored esc started acting up, I went back to brushed and am much happier.

That is sad to hear, because I was also sooooooo excited about the prospect of these motors. It does not sound like you are alone in your experience. The specs are amazing, and been very pleased with my other Tekin stuff. But, the proof is in the pudding.

When you say stutter, was it the jumpiness - kind of a lurching forward going down hill? I always thought that was a product of the worms, don't really understand it though. Chalked it up to idiosyncrasy of the worm drive and compensated driving style, but would prefer it not to be there.

[WAM]

Originally Posted by dentonmac

That is sad to hear, because I was also sooooooo excited about the prospect of these motors. It does not sound like you are alone in your experience. The specs are amazing, and been very pleased with my other Tekin stuff. But, the proof is in the pudding.

When you say stutter, was it the jumpiness - kind of a lurching forward going down hill? I always thought that was a product of the worms, don't really understand it though. Chalked it up to idiosyncrasy of the worm drive and compensated driving style, but would prefer it not to be there.

If you have a motor in your hand and you twist the pinion with your fingers...you know how it jumps from detent to detent several times per revolution? I suppose it might be going from magnet to magnet or something. I think it feels like those pauses are being amplified by the worm gear drag and so it descents in very small increments of motion, stopping in between. The stopping is like hitting a dragbrake and near the steepness limit encourages the rear tires to lift off like any sudden braking would. Not saying this is actually what happens...just what it seems like to me.

There may be some combination of factors, parts, gears etc which get around this, dunno. The smaller the pinion, the less the effect. And BTW, I involved Tekin and while they were very cooperative they (Ty) ultimately acknowledged/reproduced the problem on his personal Losi and had no current solution.


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[Olle P]

I've had the "stutter" with brushed and brushless alike. I think the motor's minimum speed is one relevant factor to consider, in combination with the worm's friction and the general "slop" of the wheel axles.

[GrimJeeper91]

I'm still running my ROC412 but I have lost the ability to crawl down steep slopes as slow as I would like. I was running a Holmes Torque Master Pro 45T motor and could crawl down steep grades as slow as I wanted. With 2S the ROC412 2300kv has more torque and wheel speed. The ROC could definitely power through obstacles that would stall the TM motor. When I went to 3S it opened up lines on my rocks that I couldn't make before (due to wheel speed). When I need really good down hill control I run 2S. When I need wheel speed I run 3S. What I need to do is swap the TM back in and see how it does with 3S on steep descents. If I could get a redo I'd probably stay with the Holmes brushed motor so I guess the ROC wasn't worth the money. On the flip side I have a Wraith that is an all around rig that I think the ROC will excel in. I just need the more time to experiment.

[z50king]

I have always had the down hill hop with ever motor system I had in the lcc. I think it's a product of spool slop, which I don't care to shim up correctly because I don't comp it enough. It only happens to me on steep, long, smooth downhills. I don't notice it on dirt

Sent from my PG86100 using Tapatalk 2

[WAM]

No I run both the ROC brushless and a variety of beefy brushed motors. The brushed motors are dead smooth even so slow it's hardly moving. My current one is a prototype Brood Axle Buster monster motor and I think this will become the Losi motor of choice once fully developed and in general sale. It may require more maintenance than some, but we're used to that with worms anyway. EeePee has written a few times about his Axle Buster #1 and I think he's of the same opinion. Kinda pricey currently...that may keep it from broad acceptance.

[JMiller2065]

Well I decided to stick with the brushed motor and I have yet to burn one up (knock on wood), but I also don't have the wheelspeed that others have but I've developed my driving style around it. Now if I could do break overs as well as the Axial rigs with bent links. I do get them on side hills and steep down hills though.

[ukd73]

I have the roc 3100 kv on 3s and 16t pinion matched with mmp esc and if you use castle link and make a custom throttle curve that is non linear up to about 60% then linear from that point to 100% throttle she will creep smoothly and have good wheel speed when you need it. Punch control 50% reverse 50% no drag brake needed. I love my setup took me a while to get it right but was worth the effort. I have brushed motors in other rigs but the torque and wheel speed at higher throttle input is the best of both worlds with the roc. I may have got lucky and found the right setup for my night crawler. Down steep inclines no stuttering. I also have some expo on the throttle too can't rember my setting but I'm not going to change anything she is slow and smooth with a lot of wheel speed if you needed it. I think it was worth the money and time it took to dial it in. You just have to tinker with the throttle curve and once you get it right you will love this setup. If your not willing to experiment it will stutter and lurch forward with no custom throttle curve that is true.