Granite Looking at some minor upgrades to my mega 550

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Freelander

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Arrma RC's
  1. 4x4-Mega
  2. BigRock 4x4
  3. Granite
  4. Typhon 3s
Ok. So I shredded the spur gear and learned what a slipper clutch is. Probably back that off a bit.

Totally stock, 2S LiPO battery.

I have questions about putting 17T 48P pinion on: it'll work with the stock gearbox? No need for the adjustable aluminum motor mount? Meshes with the 87T spur gear I will be replacing?

The AR310866 is supposed to be an upgrade drive shaft but it doesn't look like it just replaces the stock one: what do I have to do to install it? Do I have to disassemble the differentials or something? I can't see how it will go on the slipper clutch assembly and I have no idea how it would connect to the rear differential(?)

Can I get a metal spur gear and presuming I do that what will I break when that doesn't?

Is it possible to get a different slip clutch assembly?

Here's the thought: going with the higher tooth pinion should reduce low end torque right? I loosen the slipper clutch a bit to protect the spur and put the high speed driveshaft stabilizing thing in. Maybe that will reduce any play that could screw up the spur gear?

Any thoughts?
 
310866 is the drive to the wheels so you would need 4 of them and to replace it you need a long hex bit then there is a hole down the shaft to access the screw holding it on the out drive. So there is no reason to take apart the diffs, but you need to remove either the shock or a-arm or both. Hope that helped and welcome to the forum.
 
on that 17t pinion, that will make the motor work harder, which will generate more heat. The stock combo already is at it's limit, adding load will overheat everything in a hurry.

Hot Racing makes a drop in steel spur for the Mega trucks. But, it is often backordered.

Also, the stock spur is 91t, if you have a 87t spur, you may have purchased the wrong one. There was a 2wd Granite Mega that used a 87t (I think). The spur from the 2wd trucks will not fit the 4wd trucks.

The other upgrade path wold be the BLX slipper and adjustable motor mount, along with a 32p pinion. The BLX gears have bigger teeth, so will be tougher, even with a plastic gear. You will need to run a very small pinion - like a 9t to get close to the same ratio.
 
My mistake. Yes it is 91T. Ar310799. What can I upgrade to given the 3mm size of the spindle on the 12t motor? If I got an adjustable motor mount I could conceivably make any spur and pinion no?
 
on that 17t pinion, that will make the motor work harder, which will generate more heat. The stock combo already is at it's limit, adding load will overheat everything in a hurry.

Hot Racing makes a drop in steel spur for the Mega trucks. But, it is often backordered.

Also, the stock spur is 91t, if you have a 87t spur, you may have purchased the wrong one. There was a 2wd Granite Mega that used a 87t (I think). The spur from the 2wd trucks will not fit the 4wd trucks.

The other upgrade path wold be the BLX slipper and adjustable motor mount, along with a 32p pinion. The BLX gears have bigger teeth, so will be tougher, even with a plastic gear. You will need to run a very small pinion - like a 9t to get close to the same ratio.
Ok. The spur gear is back ordered like everywhere it seems. Including the third party hot racing metal one which would be nice. I wish I had shelled out for the 3s now. More parts available. Are there 32P pinions that fit onto the 3mm spindle of the 12T 550 motor that comes stock?
 
Ok. Ok. Super informative. After several hours I have ended up realizing how much wisdom was contained within your reply. Fair or foul I have come across what I believe is a 32P BLX slipper 57T assembly. I posted a picture somewhere and have sourced a 32P pinion that will fit on a 3mm shaft. And yes. It looks like I need a new motor. I think I will get another 550 and explode it with this experiment. I either need to mod the motor mount or sounds like or would a motor mount for a BLX allow me to use these two gears? 57T 32P spur and 12T 32P axial AT30273 with a stock mega 550 motor?
However inadvisable?
 
If you found the whole assembly from a kit breaker, great! If you are buying offical arrma parts, know that there are 3-4 baggies you need to build a whole slipper. Read thru the exploded diagrams to make sure you have everything. You will also want the adjustable motor mount, as the mega mount is pre-drilled for 48p spacing. If you cannot find the adjustable motor mount, you can just oval a hole in your mount to give you the adjustment.

If for some reason you need a stock plastic 91t spur, I have extra. Send me a PM.
 
So I actually got a 9T that fits the 3mm motor shaft on the new 550 12T motor I got. How do I warranty the one that got shrecked in 2 days? I am excited to see if this works. And eventually if I upgrade motor and esc we'll need the adjustable mount.
So I actually got a 9T that fits the 3mm motor shaft on the new 550 12T motor I got. How do I warranty the one that got shrecked in 2 days? I am excited to see if this works. And eventually if I upgrade motor and esc we'll need the adjustable mount.
FRIIG I FORGOT SOMETHING AND TOMORROW IS A HOLIDAY AAAARGH.

guess I am making my own AR310881 out of the stock mega 550 slipper shaft. Stupid bold typing.
 
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Completed 32P mega 550 granite 4x4 conversion. Now to go testing
 

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It works! I think there are two parts missing from the slipper clutch which is why the m.2.5 20mm machine screw was sticking out too far for the clutch assembly to mate with the input gear on the rear differential, I bought m2.5 x 12mm and solved that. But without the spring and stuff the clutch loosened on us twice. So we screwed that thing tight af. Works awesome.
 
Yeah. . . Eventually. It's going to cost us to keep replacing the brushed motor I am thinking. I figure we'll fry one or two more before we cough up the dough for a real motor I guess. What kv is going to be good? I saw somewhere that around 4000 was equivalent in power to 12 turns and what output ESC? 60A? Would that mean we have to replace the steering servo? If we get too powerful a motor then we'll probably shred the drive train somewhere?
Yeah! Thanks for your help regarding gear ratios. We probably would have quickly killed our new motor going from 6 something to 4 something. I think the 9T hardened steel RRP pinion I ended up with was expensive, but the cheaper axial one was 12T or nothing. I wouldn't have had a clue what to do except wait for those stock gears if the guru guy at the LHS hadn't slipped me that slipper assembly. It wasn't just drop in and go but making it work meant I learned a lot of stuff. That dude is a legend.
 
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Comparing brushed motors to brushless is a bit hard... I have a "f540" 3000kv that is pretty equal in power in my granite. But that F540 is a 380-sized motor, vs the 550 stock motor... :ROFLMAO: :ROFLMAO: :ROFLMAO:

If you don't want to mess with he rest of the drive line, then stick with a 3650 size motor, in a lower KV - 3000-3300kv, and keep the gearing low till you get a handle on how it will handle the heat. If it runs cool, add a tooth or two to the pinion. With a higher KV, you may get too much heat, and will not be able to gear down. Start with low KV to control the heat, and you can gear up to get power.

If you get the HD17t diff input for the rear diff, you should be mostly bulletproof (with a 3650) with your 32p spur.

ESC - if you get a 3650, then a 60a will be fine. If you go for a 3660, then you will want a 80a or 120a ESC.
 
Yeah. . . Eventually. It's going to cost us to keep replacing the brushed motor I am thinking. I figure we'll fry one or two more before we cough up the dough for a real motor I guess. What kv is going to be good? I saw somewhere that around 4000 was equivalent in power to 12 turns and what output ESC? 60A? Would that mean we have to replace the steering servo? If we get too powerful a motor then we'll probably shred the drive train somewhere?
Yeah! Thanks for your help regarding gear ratios. We probably would have quickly killed our new motor going from 6 something to 4 something. I think the 9T hardened steel RRP pinion I ended up with was expensive, but the cheaper axial one was 12T or nothing. I wouldn't have had a clue what to do except wait for those stock gears if the guru guy at the LHS hadn't slipped me that slipper assembly. It wasn't just drop in and go but making it work meant I learned a lot of stuff. That dude is a legend.
. Any brushless motor gona be better then that 550 motor . I got fool rc 3674 2650 Kv and 120a esc turns your car to a weapon I did get that center support brace with the motor mount 26 t with 57 spur
 

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Get rid of the 550 motor go brushless
Soooo. . . Yeah. Couple hundo later we have an esc and a motor en route. Gonna upgrade the diffs and inputs. Maybe get a new battery. Too many sunk costs and just buying a 3s blx seems like cheating. I don't want to have to look at this Mega and feel defeated or like I just abandoned it and bought a new truck. This frickin' rig is gonna fly one day and me and my kid are gonna make it so one painful breakdown after another. Then I might get myself a 3S so we can race.
 
Soooo. . . Yeah. Couple hundo later we have an esc and a motor en route. Gonna upgrade the diffs and inputs. Maybe get a new battery. Too many sunk costs and just buying a 3s blx seems like cheating. I don't want to have to look at this Mega and feel defeated or like I just abandoned it and bought a new truck. This frickin' rig is gonna fly one day and me and my kid are gonna make it so one painful breakdown after another. Then I might get myself a 3S so we can race.
Sounds like Fun!

What did you order?
 
Fully assembled differentials the 37T set and the 13T inputs, hobbywing ezrun max10, 3652 4000kv motor hobbywing, a 3660 racer star 3300kv.

Oh dude. I saw the first installment on your speed run build video! Looks sweet!

Kind if regret getting the 3652. Should have educated myself more, but maybe if we keep it on asphalt and just go for speed with that motor and try the 3660 for offroad and stuff?
 
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