Capra motor/ esc replacement questions

[high plains drifter]

Capra RTR. I've had it a couple years. Love it but hate the lack of drag brake and jerky stop/ go. Been running a HH shv500v2 for a while, love it. Time now to swap out stock motor and esc for crawlmaster 540 16t and hw wp1080.

First, Wanting to find out if that sounds like a good motor choice.

Next, Trying to figure best easiest way into this thing. I don't mind whatever it takes but not looking to turn wrenches for no reason.

Last, Any other note worthy things I should be aware of beforehand? I'll prob remove dig unit linkage and servo while I'm in there.. Guessing that's pretty straight fwd.

I just wanna make sure that I've got some sense of what to look out for while I'm in there. Don't wanna have to take it all back apart afterwards. Looks like some tight spaces in there.

Thank you guys.

 

[chilly]

I just replaced the stock ESC with a 1080 and it is a world of difference from the 'jerky stop and go' perspective. I can crawl up or down a slope at the limit of rolling or traction, and I can stop, creep a tiny bit forward, stop, roll back a bit, stop. All perfectly smoothly - unlike the stock ESC that sent you on a toboggan run downhill as soon as you gave it 1% throttle trying to crawl downhill. The drag brake held fine on mine, but it was on, then it was off and you started rolling fast. I'm pretty sure you need to enable 'freewheeling' in the 1080 settings for that behavior.

I'm on the stock motor still - I don't feel like it's holding me back... idk what I would do with a stronger motor. I don't want to go faster or jump over things, and I don't want to power through when my tire gets wedged somewhere and end up breaking driveline stuff.

The whole top of the body comes off if you remove the 4 top shock attachment screws, then the 4 horizontal long screws in the base chassis plate that connects it to the body. Then the body just lifts off - with wires connected so don't yank it.

It is a little tight in there, but I added 4ws, a big castle 10A BEC, a 2 channel light switch, and rock lights and I kept dig, and it all fits fine. Just a little tricky taking it apart with a bunch of zip ties keeping wires out of the driveshafts.

 

[high plains drifter]

Some great information there Thanks a ton!

I'm mainly looking to install the new motor in the hopes of a little more grunt/ and or smoother throttle. Recently put one in a TF2. I also would just like to do the esc and motor all at once. I haven't had any issues with the stock Capra motor but still hoping for a bit better performance with the Crawlmaster and stock spur/ pinion.

 

[DrIsotope]

If you like drag brake, maybe go with something that isn't 5-slot. There's very little reduction in the Capra gearbox, and it runs a dinky spur to keep the 'box low-profile-- I had very good fortune with a Tekin HD 35T 540, but had I to do it (it being brushed power) again, I'd go even lower, with a 45T or even maybe a 55T. I run a 900kv outrunner in mine now.

 

[high plains drifter]

Wasn't wanting to go brushless. Figured the Crawlmaster 540 16t would be a good one in here with the new esc.. Maybe not? It only being $20 was part of that decision too. Anyway.. I haven't ordered the motor yet... Wondering if there's another Crawlmaster better suited or if I should just keep the motor stock for now.

 

[DrIsotope]

The Trailmasters from HH are 3-slot. If you're doing any kind of trailing, the 35T would probably be the guy. If you're purely on rock, I'd say the 55T and gear up a few teeth. And hey, they're only 15 bucks each.

 

[durok]

Trailmaster series would give more drag brake, as they are 3-slot.

However, I don't own a Capra - just read a lot about the relatively wacky gearing on the trans.

Since you mentioned using the CrawlMaster 16t I thought I'd point out that
Holmes Hobbies makes an interesting note in his Motor Recommendations listing:

General Trail use:
55t – 35t TrailMaster Sport 540
55t – 35t TorqueMaster 540
20t – 16t CrawlMaster 540*
16t CrawlMaster Magnum 540
Puller Pro V2 Rock Crawler Motor - Stubby or Standard
Revolver 540 (Snubnose is not recommended)

*10 or 9 tooth pinion needed

Maybe just get a TrailMaster Sport 35t?

 

[high plains drifter]

Thank you guys, both. I was kinda torn between going with a 3 slot as opposed to a 5 slot. In my mind I want to say "this rig will only be on the rocks" but I also know that to get to those rocks, I often have to drive it a ways. I don't know if that is worth putting into the equation but I don't want my motor or esc getting pushed too hard, overheating, etc if I'm trailing it some distance.

Yeah, I checked out what HH was recommending and noticed what you pointed out, durok... about the suggested 9 or 10t pinion if going with the 16t Crawlmaster. Automatically made me wonder about going that route.

I did drop a Trailmaster 550 21t into my trx4 a few years ago and I've always been happy with the performance on the rocks so I'm not necessarily opposed going with a Trailmaster in the Capra.

Just gets a little perplexing when faced with slots, turns, pinions, as well as 2S/ 3S. Makes it hard to know exactly which way to go sometimes.

Stock motor is 35t so I'm not sure if it would be worth it to replace it with the Trailmaster 35t. Stock pinion is 14t. Wondering if maybe just changing the pinion out to an 11t might be a good route to go. Opinions on that would be welcomed. Thanks.

 

[bgredjeep]

I found it helpful that Holmes lists the kv ratings for their motors so you aren't just guessing about what to expect based on X turns and Y slots.

https://holmeshobbies.com/motor-recommendations

I've never run the stock capra trans (i have a 3gear in my capra-like thing), but based on pretty much every post or thread I've read it seems to not have great reduction. Based on that I would tend to look at a lower kv motor than you might for some other crawlers. Why get a motor that requires the smallest pinion you can fit?

Also, I read Holmes advice a while back to "volt up, gear down". I think the you can get the similar result, when gearing options are limited, with volt up, kv down.

I recommend 3s for sure.

 

[high plains drifter]

Thank you for the additional info. Been looking over that chart. Yep I've always run my Capra on 3S.

I really wanted to put a Crawlmaster in this thing due to it's excellent reputation for slower controlled acceleration. If it doesn't make sense to go that route, I may just stick with the factory 540. Just not sure that I'd see much benefit from another motor unless I'm willing to spend more money on a high end motor/brushless system. I just want a bit better performance but seems the benefit of the Trailmaster series might not yield much improved results. And seems that Crawlmaster Sport 16t might not be such a great motor in a rig like the Capra, geared so tall.

 

[twade984]

Thank you for the additional info. Been looking over that chart. Yep I've always run my Capra on 3S.

I really wanted to put a Crawlmaster in this thing due to it's excellent reputation for slower controlled acceleration. If it doesn't make sense to go that route, I may just stick with the factory 540. Just not sure that I'd see much benefit from another motor unless I'm willing to spend more money on a high end motor/brushless system. I just want a bit better performance but seems the benefit of the Trailmaster series might not yield much improved results. And seems that Crawlmaster Sport 16t might not be such a great motor in a rig like the Capra, geared so tall.

I briefly ran my Capra kit with a 16t Crawlmaster sport, hw 1080 and overdrive front portal gears. It got noticeably warm after moderate driving. Hotter than any of my other rigs.

Now that could be related more to the high o/d, but I didn’t keep the rig long enough to sort it out.

Personally I would get either the 16t or 20t sport motor and just try it. Pair it with the smallest pinion you can fit, and see how you like it.

As a person that values smooth start up and control, I don’t think I could enjoy driving a Capra without addressing the poor final drive ratio. Be it 3 gear/stealth x swap, small pinion and u/d gears front and rear, or even a dlux portal trans swap.

If you solve the poor gearing issue than you can run just about any motor turn/kv you want.

 

[high plains drifter]

Thank you, twade. Very much appreciate your input. Seems that a lot of people are chasing this issue due to factory transmission in this rig. And I too have been debating over-driving the front end as well. so I'm especially glad that you posted about your experience. I'll have to figure this out once I get the new esc installed and play around with the programming a little bit.. drag brake and whatnot. Then maybe I'll just have to address the motor down the road.

 

[Ots]

Earlier you said that you might take out the Dig servo and linkage. If you plan on leaving it this way, there is a spacer that needs to be put inside the case on the shaft for the Dig unit to keep it from accidentally engaging on you.

 

[high plains drifter]

Earlier you said that you might take out the Dig servo and linkage. If you plan on leaving it this way, there is a spacer that needs to be put inside the case on the shaft for the Dig unit to keep it from accidentally engaging on you.

Ah, I wasn't aware of that. Thank you!

 

[2wdx2]

I briefly ran my Capra kit with a 16t Crawlmaster sport, hw 1080 and overdrive front portal gears. It got noticeably warm after moderate driving. Hotter than any of my other rigs.

Now that could be related more to the high o/d, but I didn’t keep the rig long enough to sort it out.

Personally I would get either the 16t or 20t sport motor and just try it. Pair it with the smallest pinion you can fit, and see how you like it.

As a person that values smooth start up and control, I don’t think I could enjoy driving a Capra without addressing the poor final drive ratio. Be it 3 gear/stealth x swap, small pinion and u/d gears front and rear, or even a dlux portal trans swap.

If you solve the poor gearing issue than you can run just about any motor turn/kv you want.

Did you use the stock pinion with it ? HH recommends 9-10T, though not sure how you install anything less than 11T without modifications....

 

[twade984]

Did you use the stock pinion with it ? HH recommends 9-10T, though not sure how you install anything less than 11T without modifications....

I believe I used an 11t pinion. I think I’ve heard there’s an after market trans case that allows use of a 9t pinion, but never looked into it.


Sent from my iPhone using Tapatalk

 

[2wdx2]

that is a bit disappointing. I was about to go that exact route.
I wonder if going with 13T vs 16T makes any difference with heat.

I did think to under drive both front and rear in addition.
Is it possible to get the same ratio of 3 gear transmission with 11T and under drive both ?

 

[bgredjeep]

that is a bit disappointing. I was about to go that exact route.
I wonder if going with 13T vs 16T makes any difference with heat.

I did think to under drive both front and rear in addition.
Is it possible to get the same ratio of 3 gear transmission with 11T and under drive both ?

I haven't looked into how much you can under drive a capra axle, but its a pretty big difference in the transmission ratios. From what I'm finding, the capra trans is 1.8:1, and uses a 34t spur. Even using the smallest pinion I've heard at 9t you are only getting 6.8:1 from the trans.

The typical 3 gear should be ~2.62:1, but you have loads of options for spur/pinion to go as low as you want. Even using a mild 32pitch example at 56/12, you are over 12:1 from the trans.

 

[chilly]

I just ended up with a Crawlmaster sport 20T 540 by accident and it was only $15 so I figured I'd try it. I have a 11T and rear vanquish 10% underdrive at this point. And I didn't seem to have any issues with heat. It was a cool day - 60's - and I don't really trail it - just slow crawling. It was just slightly warm. I know Holmes recommends a 9-10T so idk if maybe the rear underdrive, or just my slow type of driving?

I think I noticed the drag brake was less though when I was testing it in the house at install - but wasn't terribly distracting on the rocks. I meant to test it on a limit-of-traction slope, but forgot to. Will try that tomorrow probably.

Overall it didn't feel worlds different from the stock motor - a bit smoother I'd say. My Vanquish Phoenix with trailmaster 550 feels like a fine swiss watch compared to the capra with either motor (both hw1080). I don't really know what makes the big difference though - I would guess it's primarily the nicer trans, not the motor. But those are the only two rigs I have experience with.

 

[high plains drifter]

I just ended up with a Crawlmaster sport 20T 540 by accident and it was only $15 so I figured I'd try it. I have a 11T and rear vanquish 10% underdrive at this point. And I didn't seem to have any issues with heat. It was a cool day - 60's - and I don't really trail it - just slow crawling. It was just slightly warm. I know Holmes recommends a 9-10T so idk if maybe the rear underdrive, or just my slow type of driving?

I think I noticed the drag brake was less though when I was testing it in the house at install - but wasn't terribly distracting on the rocks. I meant to test it on a limit-of-traction slope, but forgot to. Will try that tomorrow probably.

Overall it didn't feel worlds different from the stock motor - a bit smoother I'd say. My Vanquish Phoenix with trailmaster 550 feels like a fine swiss watch compared to the capra with either motor (both hw1080). I don't really know what makes the big difference though - I would guess it's primarily the nicer trans, not the motor. But those are the only two rigs I have experience with.

Yeah, it seems that the Capra transmission is a more prominent issue than the motor.. at least from what I've been reading recently. Unless someone chimes in with a significant and more definitive answer regarding smoothing out the Capra's throttle and overall control, I think I'll just replace the esc and leave the stock motor in there. I can't afford to experiment with different motors and try to figure out what's the best in terms of turns, pinion, spur combinations. Too much hassle and money.

Hopefully the new esc will at least get this rig to where it'll perform noticeably better than stock.