Xmaxx ultimate cogging problem, please help

[332_RC]

I got a TP4050 1950KV (4083 can) for my next build. I'm thinking it'll be plenty in a 6s chassis.

 

[332_RC]

I got a TP4050 1950KV (4083 can) for my next build. I'm thinking it'll be plenty in a 6s chassis.

And! It's a D wind so better for bashing! Won't burn up like those Y wind Castle motors.

 

[Greywolf74]

I'd be willing to bet it's a combination of the ESC, motor, and gearing. The ESC and Motor you're running are both small for that rig. Will they work? Yes. Are they being pushed close to their limits? Yes. Now you go and replace the stock Mod1 gears with Mod1.5, and now you're asking the motor and ESC to work even harder. I'd be willing to bet dropping teeth on the pinion would fix the issue, going back to the original stock mod1 gearing could possibly fix the issue, or using a bigger motor/ESC combo could also possibly fix the issue. You might even be able to get away with just using a torque-ier motor like the 1100kv EZRUN MAX 56118 SD G2 motor with the Max6 and mod1.5 gearing, but that motor is recommended to be run with the MAX5.

Personally, if it were me, the first thing I'd have done was went back to mod1 gearing but since you already ordered the MAX5, I'd go ahead and order the 1100kv motor and call it a day. That combo will push that mod1.5 gearing NP.

Just as a side note, I've been using Castle since I started in this hobby and Id buy a Castle before a HW any day of the week and twice on Sunday. I've never had an issue with a Castle ESC unless it was defective out of the box (happened once), or unless it was just really old, and I was pushing it hard which will kill any ESC eventually. Hell, I've still got a Castle MMM in one of my rigs, and It's still running. That ESC is from 2012-ish. Anyone that says Castle is junk is an idiot IMO.

 

[KnowAir]

I'd be willing to bet it's a combination of the ESC, motor, and gearing. The ESC and Motor you're running are both small for that rig. Will they work? Yes. Are they being pushed close to their limits? Yes. Now you go and replace the stock Mod1 gears with Mod1.5, and now you're asking the motor and ESC to work even harder. I'd be willing to bet dropping teeth on the pinion would fix the issue, going back to the original stock mod1 gearing could possibly fix the issue, or using a bigger motor/ESC combo could also possibly fix the issue. You might even be able to get away with just using a torque-ier motor like the 1100kv EZRUN MAX 56118 SD G2 motor with the Max6 and mod1.5 gearing, but that motor is recommended to be run with the MAX5.

Personally, if it were me, the first thing I'd have done was went back to mod1 gearing but since you already ordered the MAX5, I'd go ahead and order the 1100kv motor and call it a day. That combo will push that mod1.5 gearing NP.

Just as a side note, I've been using Castle since I started in this hobby and Id buy a Castle before a HW any day of the week and twice on Sunday. I've never had an issue with a Castle ESC unless it was defective out of the box (happened once), or unless it was just really old, and I was pushing it hard which will kill any ESC eventually. Hell, I've still got a Castle MMM in one of my rigs, and It's still running. That ESC is from 2012-ish. Anyone that says Castle is junk is an idiot IMO.

I agree, though I won’t be trading off any HW esc’s. Can’t fix what ain’t broke. I have15 year old HW. I’m not arguing Castle isn’t better, just not interested in paying more than I need to.

 

[Greywolf74]

I agree, though I won’t be trading off any HW esc’s. Can’t fix what ain’t broke. I have15 year old HW. I’m not arguing Castle isn’t better, just not interested in paying more than I need to.

Nothin' wrong with HW, I wasn't thrown shade at 'em. I'm just saying Castle makes good stuff.

 

[KnowAir]

Nothin' wrong with HW, I wasn't thrown shade at 'em. I'm just saying Castle makes good stuff.

Me either brother. Like I've said before, I'm content with lower performance than most. I always say I'm going to see what all the fuss is about with the Castle and Tekin.. one of these days. Of course that necessitates batteries that can feed them too. The amazon crap ain't gonna cut it. . much less the Temu batteries I just bought! I'm such a sucker! 2x4s Ovonic 9.0ah,$33? Well, they didn't catch fire yet.. actually pretty good for a stock 8s rig. LOL

 

[WickedFog]

Personally, if it were me, the first thing I'd have done was went back to mod1 gearing but since you already ordered the MAX5, I'd go ahead and order the 1100kv motor and call it a day. That combo will push that mod1.5 gearing NP.

The MOD doesn't have any affect on load unless the gear ratio changed. If you have a MOD1 gearset at 1.75:1 ratio, it's going to be the same load as MOD1.5 gearing at a 1.75:1 ratio. It's just bigger teeth, which are more durable, and will handle more wear before the mesh becomes a problem.

 

[Greywolf74]

The MOD doesn't have any affect on load unless the gear ratio changed. If you have a MOD1 gearset at 1.75:1 ratio, it's going to be the same load as MOD1.5 gearing at a 1.75:1 ratio. It's just bigger teeth, which are more durable, and will handle more wear before the mesh becomes a problem.

You’re absolutely right that the gear module itself doesn’t change the load on the drivetrain if the gear ratio remains constant, and MOD1.5 does offer increased durability. However, the larger teeth of MOD1.5 gears do add some rotational mass, which will slightly increase inertia and could contribute to cogging at low speeds, especially in systems already near their limits. Additionally, ESC settings or motor tuning might need adjustments to compensate for the subtle differences in drivetrain dynamics when switching gear modules. While the effect is small, it’s worth considering.

 

[CertifiedMike]

https://www.upt-usa.com/mechanical/reduce-gear-friction
All ways gear changes can affect efficiencency.
If nothing else is making sense to cause your problems, looking at your gearing makes a lot of sense.

 

[WickedFog]

You’re absolutely right that the gear module itself doesn’t change the load on the drivetrain if the gear ratio remains constant, and MOD1.5 does offer increased durability. However, the larger teeth of MOD1.5 gears do add some rotational mass, which might slightly increase inertia and could contribute to cogging at low speeds, especially in systems already near their limits. Additionally, ESC settings or motor tuning might need adjustments to compensate for the subtle differences in drivetrain dynamics when switching gear modules. While the effect is small, it’s worth considering.

The OD of a 54T MOD1 (stock spur) gear is 57mm diameter. The diameter of a 35T MOD1.5 gear is 55.5mm. The weight of the gear here would possibly show the MOD1 gear as the heavier gear, if they were the same design.

For a pinion, it won't be much different between the two.

But the stock X-Maxx has a heavy outer ring, then a cush drive assembly bolted in the middle of it. It may be quite a bit heavier stock.

 

[KnowAir]

Interesting on the 1 vs 1.5 gears. I don't like how the 1.5 sound, combined with my low power supply I'm sticking w/mod 1, LOL. But good info indeed.

 

[WickedFog]

Interesting on the 1 vs 1.5 gears. I don't like how the 1.5 sound, combined with my low power supply I'm sticking w/mod 1, LOL. But good info indeed.

You will hear more gear noise with bigger MOD gears, but that's to be expected. I know, it sounds like they're grinding away. But it kinda reminds me of a gear drive on a small block, and there ain't much better sound except a bigass roots Supercharger

 

[Greywolf74]

The OD of a 54T MOD1 (stock spur) gear is 57mm diameter. The diameter of a 35T MOD1.5 gear is 55.5mm. The weight of the gear here would possibly show the MOD1 gear as the heavier gear, if they were the same design.
View attachment 211877

For a pinion, it won't be much different between the two.

View attachment 211878

But the stock X-Maxx has a heavy outer ring, then a cush drive assembly bolted in the middle of it. It may be quite a bit heavier stock.

It's 56mm and 55.5mm (outer_diameter = (number_of_teeth + 2) * module), but we're not talking about the same gear ratio as stock. Stock gearing according to the web is 18/54 (3.0:1) and hes running 20/35 (1.75:1). Huge difference from stock. Also explains why he's not doing standing backflips.

 

[Greywolf74]

(Also, the actual weight isnt determined by OD alone)

 

[WickedFog]

I'm not sure what the stock X-Maxx gears are. I wasn't talking about that. I was saying the weight difference of a set of gears of the same ratio, if designed exactly the same, same lightening holes, etc will show the MOD1 gears to be heavier. There is more material removed from a MOD1.5 gear than a MOD1, because the root diameter of the MOD1.5 gear is smaller.

 

[KnowAir]

Unrelated, but I bought a "Crazy Racer" branded 50t mod 1 spur for my Xmaxx. I wanted to run 20/50 gearing, which is great as long as ambient temps are on the cold side. I never stripped any of the TRX sintered crap, but since switching to this cheapo spur gear I've tore up at least 4 or 5 different pinions. Including 2 Tekno pinions.. so much for the budget spur gear, LOL. I tried a couple HR pinions, first one didn't last 5 min. I'm well versed w/gear mesh, so I have to imagine the spur gear is to blame. I think I'm going for the TRX machined steel spur next.

 

[KnowAir]

You will hear more gear noise with bigger MOD gears, but that's to be expected. I know, it sounds like they're grinding away. But it kinda reminds me of a gear drive on a small block, and there ain't much better sound except a bigass roots Supercharger

Subjective for sure! Some love it, and while I don't hate the sound, it does sound sickly to me. But given my Xmaxx's new found appetite for pinion gears, I might better reconsider my opinion on what's more important. Dollars vs senses, LOL.

 

[WickedFog]

Unrelated, but I bought a "Crazy Racer" branded 50t mod 1 spur for my Xmaxx. I wanted to run 20/50 gearing, which is great as long as ambient temps are on the cold side. I never stripped any of the TRX sintered crap, but since switching to this cheapo spur gear I've tore up at least 4 or 5 different pinions. Including 2 Tekno pinions.. so much for the budget spur gear, LOL. I tried a couple HR pinions, first one didn't last 5 min. I'm well versed w/gear mesh, so I have to imagine the spur gear is to blame. I think I'm going for the TRX machined steel spur next.

Got any pics of a the mangled pinions? Any number of these measurements being off on that spur could cause premature pinion wear. The pinion has less surface area, so it's gonna wear first if there is a problem with the machining.

 

[Greywolf74]

I'm not sure what the stock X-Maxx gears are. I wasn't talking about that. I was saying the weight difference of a set of gears of the same ratio, if designed exactly the same, same lightening holes, etc will show the MOD1 gears to be heavier. There is more material removed from a MOD1.5 gear than a MOD1, because the root diameter of the MOD1.5 gear is smaller.

That's an interesting fact that I wasn't aware of between the root diameters on mod 1 & 1.5, but given that the ratio is almost half what it was, makes it a bit beside the point in this particular instance. I do enjoy learning something new though

 

[WickedFog]

It's 56mm and 55.5mm (outer_diameter = (number_of_teeth + 2) * module), but we're not talking about the same gear ratio as stock. Stock gearing according to the web is 18/54 (3.0:1) and hes running 20/35 (1.75:1). Huge difference from stock. Also explains why he's not doing standing backflips.

I don't have a running X-Maxx, so I have no idea if 1.75 works or not with his setup. When I was working on ours, I watched vids of ones running pretty damn good, and recorded the gearset they used for reference later and popped them into that spreadsheet. Whether they are too steep or not, I have no idea. But the OP's ratio is right in that range I found others to be using. The stock motor and ESC are underpowered according to what I found (and from JT). Swapping to the HW setups allows for taller gearing. JT's was overheating before he swapped to the Max5. Or was his a 6 also? But he did have a few mods on it before he swapped electronics