Fitting a 10T pinion gear

[hibbs]

I’ve seen people mention using a 10T pinion gear. I have one on my motor and I ground the slots to adjust mesh a little longer but the motor can is tight to the trans housing. I can’t get the mesh any tighter. It’s pretty loose. Is there something else you guys are doing to make that fit? I’d really like to take some strain off this mamba micro. If not a mamba x is going to get shoehorned in here somewhere.

[Still Bill]

You didn't mention the motor; but how many mounting holes for the screws are present on its can?

If there are two pairs of mounting holes, you can go down to a 9T pinion by selecting the two holes on the can furthest from the center of the chassis. Like what I diagram below.

X O < top row of holes (screws go at X locations)
( o ) < motor shaft
X O < bottom row of holes

Important thing is to not use mounting holes that are directly opposite each other. No other work required.

Works with most cans having dual pairs of mounting holes. Note: Holes located at 90 degrees to each other do not work. The Holmes Crawlmaster Pro is one such motor with correct hole placement; but, it is brushed. My Hobbywing Xerun Axe brushless has 6 holes which allow for doing the same mounting trick. Not sure about the hole placement on any other brushed/brushless motor cans.

[punkindrublik]

Originally Posted by hibbs

I’ve seen people mention using a 10T pinion gear. I have one on my motor and I ground the slots to adjust mesh a little longer but the motor can is tight to the trans housing. I can’t get the mesh any tighter. It’s pretty loose. Is there something else you guys are doing to make that fit? I’d really like to take some strain off this mamba micro. If not a mamba x is going to get shoehorned in here somewhere.

11t it the smallest I've seen or heard of (and I've got one in mine). If you're can is hitting the trans case, you're only real option is to grind some meat off the case itself.

What motor/kv you running? My micro X is having no problems on an 11t, but I'm only running a PP Stubby 2200kv.

[Panther6834]

Originally Posted by hibbs

I’ve seen people mention using a 10T pinion gear. I have one on my motor and I ground the slots to adjust mesh a little longer but the motor can is tight to the trans housing. I can’t get the mesh any tighter. It’s pretty loose. Is there something else you guys are doing to make that fit? I’d really like to take some strain off this mamba micro. If not a mamba x is going to get shoehorned in here somewhere.

I believe you misread...several people have tried a 10T, but, like you discovered, couldn't get the mesh set properly. With the stock motor plate, you can only use down to an 11T. A couple of people have modded their motor plate, lengthening the slots closer towards the motor, thus allowing use of a 10T, but if the mod isn't perfectly straight, and the "extension" isn't enough (or too much), that could cause problems.

There is, however, a solution - Vitavon Racing is offering (through his eBay store) a machined aluminum tranny housing, which can handle down to a 9T pinion. Siggy already received his, and it looks outstanding. Hoping mine arrives by this Friday, as I'm heading to Vegas the following day, for Thanksgiving week, and I'm taking my goat with me.

~ More peace, love, laughter & kindness would make the world a MUCH better place

[m59y]

Simple solution - use a lower kV motor!

[Panther6834]

Originally Posted by m59y

Simple solution - use a lower kV motor!

With off-road racing, since the motors are typically started by ROAR, USVTA, etc, rules, it's all about the spur-pinion pairing. With the Capra, there's no spur options, so it becomes a motor-pinion pairing thing...in other words, it's not just about the motor...so, "simple solution - use a lower kV motor" isn't exactly the 'solution'.

I don't know what you're using, but I know that, with the 2080kV 'Slate' I'm using, along with an 11T pinion, I feel it's still just a little too fast. Although the Capra is my first crawler, and I'm still learning to "go slow", I didn't want it toooooo slow, thus the reason I chose the 2080kV...I felt it should be a nice "midpoint". I'm thinking/hoping that a 10T, or maybe even 9T, will have it "just right" (once I receive the Vitavon tranny case), so, I can understand why hibbs wants to user a smaller pinion.

~ More peace, love, laughter & kindness would make the world a MUCH better place

[Robbob]

You could try something like this ....

Crawford Performance Engineering : CPE-MOT4: Clodbuster Adjustable Motor Mounts - $11.99

Attach the motor half way in the plate - trim and cut screws coming through - nut the screw and adjust.

Just an idea ......

[hibbs]

Wow thanks everyone for your replies and help. I only drove the truck in a comp for about 15 mins. It overheated and would barely move. I had just enough time to get it built and ready for the comp and didn’t get to test at all. It was dumb on my part. It’s got a Holmes stubby 2200. It’s a setup others are using fine. I took it apart to work on the electronics and add overdrive to the front. I was gonna drop a smaller pinion to take some burden off the esc.

I thought I saw John Holmes day they put a 10T on their shop Capra but maybe that was 11t and I misread. I’ll order an 11t

If others are happy with the same setup I have maybe I need to spend some time working with it. I find no binding in my drivetrain. I do have a CC BEC running 2 Savox 1210 servos for 4WS but I didn’t think that would hurt the esc. The battery was too hot to hold. Perhaps it was the battery that couldn’t keep up. I’ll work on it and ask for more help if needed.

Thank you all so much!!

[punkindrublik]

Originally Posted by hibbs

The battery was too hot to hold. Perhaps it was the battery that couldn’t keep up. I’ll work on it and ask for more help if needed.

Thank you all so much!!

No crawler battery should be getting hot. You've got a problem somewhere for sure.

[hibbs]

Originally Posted by punkindrublik

No crawler battery should be getting hot. You've got a problem somewhere for sure.

Oh for sure usually none of my electronics get more than barely warm. It was just a stupid rush job. I barely even test drove it. Was working fine at the comp but on the second 10 gate course power fell off noticeably. I tried to finish the course but quit. I shouldn’t have done it that way but is what it is. Now I just need to spend some time and figure out what’s the matter. Something is pulling way too much juice.

[m59y]

Originally Posted by Panther6834

With off-road racing, since the motors are typically started by ROAR, USVTA, etc, rules, it's all about the spur-pinion pairing. With the Capra, there's no spur options, so it becomes a motor-pinion pairing thing...in other words, it's not just about the motor...so, "simple solution - use a lower kV motor" isn't exactly the 'solution'.

I don't know what you're using, but I know that, with the 2080kV 'Slate' I'm using, along with an 11T pinion, I feel it's still just a little too fast. Although the Capra is my first crawler, and I'm still learning to "go slow", I didn't want it toooooo slow, thus the reason I chose the 2080kV...I felt it should be a nice "midpoint". I'm thinking/hoping that a 10T, or maybe even 9T, will have it "just right" (once I receive the Vitavon tranny case), so, I can understand why hibbs wants to user a smaller pinion.

~ More peace, love, laughter & kindness would make the world a MUCH better place

I agree if you are doing offroad racing in a particular motor class (17.5, 13.5, etc) which I also do, but with crawlers, this is not the case. I took the alternate path than you and did not want the Capra too fast, so went with a 1200kV motor. I'm now running an 18t pinion (max that fits) as it was too slow with the 14t. If I was to do again, I would go with an 1800kV since using pinions of 11t or 18t would be similar to what I have now on the low end or to a 2300kV/14t combo on the high end. It would be nice though if there were different spur gears so that motor selection was less important. Picking a motor with lower kV that works within the 11-18t pinion range seems simpler to me than trying to find ways to go smaller and smaller in pinion size. Larger pinions also end up giving a more efficient drivetrain.

[punkindrublik]

My setup ended up being

With the PP Stubby 2200kv and an 11t pinion it creeps nicely (and I'm crawler, not a trailer). I do have a nice curve set in my ESC programming though (which I think a lot of people forget about), but the combination proved to be perfect for this rig IMO.

[Panther6834]

Originally Posted by punkindrublik

My setup ended up being



With the PP Stubby 2200kv and an 11t pinion it creeps nicely (and I'm crawler, not a trailer). I do have a nice curve set in my ESC programming though (which I think a lot of people forget about), but the combination proved to be perfect for this rig IMO.

Would you mind sharing your ESC settings? Your motor/pinion is similar to many of ours, so it could help others. Initially, I tried programming the curves via the Tx, but that hasn't been working out as well as I'd hoped...so, maybe, programming curves via the ESC might prove a better solution.

~ More peace, love, laughter & kindness would make the world a MUCH better place

[punkindrublik]

Originally Posted by Panther6834

Would you mind sharing your ESC settings? Your motor/pinion is similar to many of ours, so it could help others. Initially, I tried programming the curves via the Tx, but that hasn't been working out as well as I'd hoped...so, maybe, programming curves via the ESC might prove a better solution.

~ More peace, love, laughter & kindness would make the world a MUCH better place

Just follow John Holmes video on ESC settings. The only thing I set differently was reverse at 50%.

https://www.youtube.com/watch?v=6wvH4A_VqTs&t

[Panther6834]

Originally Posted by punkindrublik

Just follow John Holmes video on ESC settings. The only thing I set differently was reverse at 50%.



https://www.youtube.com/watch?v=6wvH4A_VqTs&t

Thanks. For all of his vehicle I've watched (the serious ones, as well as the "goofy" ones), something I missed this one. Thanks. Have a virtual coffee on me.

~ More peace, love, laughter & kindness would make the world a MUCH better place

[svt923]

Originally Posted by m59y

Picking a motor with lower kV that works within the 11-18t pinion range seems simpler to me than trying to find ways to go smaller and smaller in pinion size. Larger pinions also end up giving a more efficient drivetrain.

There has been a great deal of information shared by Mr. Holmes Hobbies on this topic over the past 10+ years but this quote seems to get right to the point:

Originally Posted by JohnRobHolmes

Volt up gear down. Or motor up and gear down. It is never ever a better idea to use a lower kv with higher gearing in a crawler.