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Axial - Project 2.0

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Instead of taming it down with the throttle curves, you need to lower your gearing. That will reduce the wheelspeed and make it A LOT smoother off the lines.

If you're running the stock 14 tooth pinion, that's what the problem is on that high voltage. The best thing you can do with a crawler is "Volt up, gear down!" so your half way there. I would try a 12 tooth.
 
I don't want to kill off the wheel speed too much, it makes a great power blast for giving it a burst when it doesn't want to get up something :)

It's not that it doesn't go slow, it does, and it crawls superbly when it is slow, I just keep dropping off the end of the 'slow crawly speed' scale too soon, which I can iron out using the throttle curve on the ESC.

Plus I'm struggling to find a 12T or 10T 48P pinion here, and I can't find any bigger Axial spur gears at all. Hot Racing do a nice 9-10-11-12 set of 4 pinions, but I can't find a vendor.
 
lots of companies make pinions that you can use, any standard size 540 pinion will work. RRP makes a 12 tooth, as well as companies like Traxxas, Losi, Associated, HPI, etc... I'm going to order the Hot Racing set just because they're geared so much lower that what I've been able to find, but you shouldn't need anything less than a 12 or 13 tooth pinion. I'm only going to a 9 or 10 tooth because I'm running a 7 turn cobalt on 11.1 volts.
 
lots of companies make pinions that you can use, any standard size 540 pinion will work. RRP makes a 12 tooth, as well as companies like Traxxas, Losi, Associated, HPI, etc... I'm going to order the Hot Racing set just because they're geared so much lower that what I've been able to find, but you shouldn't need anything less than a 12 or 13 tooth pinion. I'm only going to a 9 or 10 tooth because I'm running a 7 turn cobalt on 11.1 volts.

I eventually intend to run a 7T Cobalt (won't be until later for now though), albeit on 9.9V, so a 10T will probably be handy to keep around.

The problem I have is the Axial is a 48 Pitch gear and I can only find 32 Pitch sets here. Kind of a poser...
 
The 10 turn or 7 turn will work on that voltage just fine. I've run both on 11.1 and I like the 7 turn the best because of volting up and gearing down. I will be running two 7 turns in my berg build.

Here's some pinions. Maybe you could get the part numbers and then search online at you England distributors and find them. I know they've got to be available over there. It's what the associated RC10 stuff runs if that helps. http://www3.towerhobbies.com/cgi-bi...=RRPC1014&L=RRPC1324&S1=48P&S2=PINION&S3=&S4=

http://www3.towerhobbies.com/cgi-bin/wti0091p?&P=SM&C=CLC&V=ASC
 
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I got a 12T spur and it's pretty much fixed the wheel speed issue. It's back to where it was on 7.2V. I'm still gonna go for a bigger spur too and see if I can use those extra volts for a bit of climbing power :)
 
You should already have more torque by increasing the voltage and lowering the gearing. You can fine tune it with the spur gear of the pinions, but I find that the pinions are cheaper and easier to get than the spurs. However, you're in a whole nother country lol. Since you're not going fast enough to create heat like with a nitro, you don't have to worry about only changing the pinion gear a few teeth without changing the spur gear, etc... I talked to who I consider to be the foremost crawling expert because I was worried about changing the pinion so much and not changing the spur gear. He explained that it's the heat buildup at high speeds that causes the gears on a racing type rig to not work out together, and since we aren't going fast, there's not any heat created to speak of that was cause that sort of damage. Just thought I would pass on the info, I found it quite useful.
 
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I'm just going for absolute maximum torque for my volts here. The spur doesn't have as big and effect for sure, but it's still a bit extra. Plus I need a new spur gear so I guess I might as well try fitting a larger one.
 
A lot of guys use the kimborough (sp.) and associated spur gears, but I have no idea if they just bolt right on or if they do a slight mod to get them to fit right.
 
No matter, I ordered a hot Racing 89T aluminium spur gear and a set of 12, 11 ,10 ,9T Pinions. I got fed up of scrabbling around over here in the end and decided to import them. They are only little so hopefully they'll get in under the customs radar :)
 
A bit more picture-age for you:

2832843990_a739b8d773.webp

2832844286_a5e56002b0.webp

2832844138_a2ddf640a0.webp
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This truck gets better every time I take it out. I've only got 2 weights at the front and 1 at the back on each of the Phatties butthat's just enough to let it crawl without being weighted down and having the wheel weights pull it off the rocks. It's still got all it's grip an poise it used to have along what this morning were REALLY slippery parallel wooden poles in the middle of my course. The Delrin rims are heavy themselves so I didn't need a lot of wheel weight, i ran 4 front and 2 rear and found it was so heavy it wouldn't blaance on anything.

Big thumbs up to Charlie, he was of course right again, running Pro Line memory foams with 1x 3mm air hole in each rim makes the tyres stick like glue to the rocks, I was getting really good crawling results even with the wet rocks and tyres. I was even getting passable traction on the poles and the logs and the wood is like oil slick slippery when it's wet.
 
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looks good webbage. did u end up using a turnbuckle for the steering problem?
 
Thanks :D

I haven't got a turnbuckle one sorted out yet. It's okay as it is for now, but I'll get my A.R.S. in gear at some point and buy one for it so I can fine tune the steering a bit better.
 
Big thumbs up to Charlie, he was of course right again, running Pro Line memory foams with 1x 3mm air hole in each rim makes the tyres stick like glue to the rocks, I was getting really good crawling results even with the wet rocks and tyres. I was even getting passable traction on the poles and the logs and the wood is like oil slick slippery when it's wet.[/QUOTE]

I'm glad to hear that you've got the tires breathing, and even more glad that they're working good for you. Welcome to the traction side of life my friend!
 
I got a Robinson Racing 13T pinion through today and I'm gonna fit it ASAP. I found out on Saturday while I was dropping in on a guy locally that is getting into crawling from other RCs, that the pinion grub screw is fouling the spur gear and is chewing the edge of it. Given the difference the 12T made, it ought to be okay on a 13T for now, and I'll drop it back to 12T when I get the Hot Racing set and the new Spur from the US.
 
It sounds like the grub screw is the wrong size, or you haven't machined a flat spot on the pinion yet. Which motor are you running? It seems like you should have been able to adjust the pinion gear so that the set screw didn't touch the spur.
 
The problem is actually the grub screw is in the wrong place, I looked at the original 14T last night and the new 13T and they both have the grub screw closer to the motor casing (further into the non toothed part) than the one I fitted. Even with the 12T I have on atm slid right back against the end of the motor the grub screw still fouls on the edge of the spur teeth. I even filed the pinion grub down and it still catches. It is quite an old looking pinion gear, it's not a Robinson Racing one either (which my 13T is) so I guess it wasn't made to a the pattern Axial, HPI and R/R use.

It's no biggy, I'll pull it off, clean the teeth up on the furry bits on the spur gear with a sharp knife, and put the 13T on for now.

EDIT: Change of plan. My Hot Racing pinion set and aluminium spur turned up today, so I'll pull both off the Axial and fit a 12T + 89T Hot racing set and see how it performs.

Here ya go:

Exhibit A:
pinions.JPG


Exhibit B:
89t-spur.JPG
 
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Well I fitted em. The Pinions are a real pain to do if you fit them to an Axial. You need the slab of aluminium motor plate if you are using the stock motor mount as the shank part on the pinion is way too deep to fit otherwise. You really struggle to fit them in situ because to get them far enough back you almost can't reach the grub screw. I managed it just about. I would probably say this wouldn't be an issue if you use an East End Machining Motor Plate.

If you have the patience then take the motor and transmission assy. out and do it on the bench. I did it in the truck and almost tied my hands in a knot in places. You will need longer mounting screws if you use the spacer plate also as the Axial-supplied screws aren't long enough. I got a nice long pair with my Castle Sidewinder (of all things!!) which did the job. If you don't have those a pair of M3x15mm socket head screws will do.

The 89T spur is an easy one-off, one-on fitment. It doesn't feel like it's gonna fit on the plastic locating pins on the spur carrier, but it will if you push it together and it nips up nicely when you put the screws in. Only not here is that if you use small pinion gears (13T or smaller) on the motor, and you use an 89T spur, accessing the motor mounting screws to tighten them can be interesting. I used a ball-end hex driver to do them up tight, as I couldn't get to the upper one straight-on (you can never get to the lower one straight-on anyway easily).

Firt thing I noticed, after setting the mesh and lubricating the spur genreously is the gears are very loud. I guess metal-on-metal makes a louder noise than metal-on-plastic. I did lubricate it very thoroughly, it was so well lubed the spur was flicking grease off at full throttle. The sound is consistent, and the pinion is running n the right place and nothing is fouling either gear, it's just really loud and whiney.

Is this normal or have I set the mesh wrong, or got the gears out of whack?
 
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