Senton Senton 4x4 gearing for 2600kv

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.
Messages
24
Reaction score
10
Arrma RC's
  1. 4x4-Mega
  2. Senton 6s
So I recently got a brushed Senton in a trade. After I get it fully running, I will be converting to BLX driveline (diffs, slipper, etc) My main problem right now is that my gearing maxed out on my 2600kv 3660 motor, is not enough. I put everything in the gearing calc, and it says top speed on 2s is about 20mph. Even with the BLX Gearing (diffs & spur/pinion), it was quite mild. I was wondering if there are any smaller spur gears that fit the BLX or Mega slipper clutch that I can use rather than getting a higher KV motor.

I did more calculating and found that a 4300kv motor is perfect for my application, but I'd really rather not buy a new motor immediately
 
The brushed Mega motor is a 12 turn wind motor Can. So in keeping with stock gearing, The higher 4300kv brushed motor is what you needed ( a much closer match to the 12T Brushed motor). Your gearing calculations are correct...unfortunately that wasn't considered when you purchased the slower (yet higher torque) 2600Kv motor. If it were me, I would not focus on changing out the gearing, but get the correct motor. I think it would cost more and create more work than needed. Just buy the correct motor. And make sure you have a decent fan on that 4300Kv motor if you choose it. Just my thoughts.?‍♂️
Others may chime in. :cool:
 
The brushed Mega motor is a 12 turn wind motor Can. So in keeping with stock gearing, The higher 4300kv brushed motor is what you needed ( a much closer match to the 12T Brushed motor). Your gearing calculations are correct...unfortunately that wasn't considered when you purchased the slower (yet higher torque) 2600Kv motor. If it were me, I would not focus on changing out the gearing, but get the correct motor. I think it would cost more and create more work than needed. Just buy the correct motor. And make sure you have a decent fan on that 4300Kv motor if you choose it. Just my thoughts.?‍♂️
Others may chime in. :cool:
I figured so, but it was worth a shot lol. I had the motor laying around from another basher that has been retired, so I figured I'd just swap that entire system over. Thanks for the help, I'll look for a decent fan. I was pretty excited that my old 2600kv motor matched the blue on the body, oh well ?
 
Yeah, I have a bin full of motors I play with.
On 2S a 2600kv motor will get you 19,240 RPMS.
The 4300kv motor will get you 31,820 RPMS.
I usually calculate what size KV motor I need by determining RPMs that will result with the type of Lipo I will be using.
Multiplying Volts of a Lipo times the KV of the motor gives you RPMs. Most BLX motors can run up to 50k RPM's. But getting close to 40K rpms on a 36mm size Motor can is my target. At least if speed is your objective. Remember that you lose torque, the higher the KV you go. There is a trade off.
31,820 RPMs seems like a balanced basher setup. Speed and torque. :cool:
BTW, that 2600kv motor would be a great Trail Crawler motor.
 
Last edited:
Can't you just run a larger pinion? Am I missing something?
^^^@CD02 said he already maxed out his gearing.?‍♂️

I would try a 3S Lipo with that 2600kv motor as one alternative. May have to gear down a bit to find the sweet spot for the 3S. :cool:
Generally, you volt up...gear down and vice versa.
 
Last edited:
^^^@CD02 said he already maxed out his gearing.?‍♂️

I would try a 3S Lipo with that 2600kv motor as one alternative. May have to gear down a bit to find the sweet spot for the 3S. :cool:
Generally, you volt up...gear down and vice versa.
What does maxed out mean? If the motor has enough torque, can't we just go up to something like 28t? That should be plenty with the blx spur gear.
 
@CD02 said he was maxed out whatever that means. Already using the largest pinion??‍♂️
He was considering a smaller spur gear at this point.
But, I feel he needs to run the 2600kv on 3S or get a 4200kv motor that translates with the stock gearing and the stock brushed 12T motor much better.
His gearing is just maxxed out and he lost most of his top end with the 2600kv running 2S. :cool:
 
Last edited:
Maybe "maxed out" in terms of Arrma pinions? But any 5mm mod .8 pinion should do the job, right?
I would prefer staying with the lower kv motor.
 
What does maxed out mean? If the motor has enough torque, can't we just go up to something like 28t? That should be plenty with the blx spur gear.
The Arrma 3S BLX motor mount only goes up to a 26t and the Mega motor mount only does 26t. There is no way for me to possibly go further up on the pinion. On my previous basher, it was fine since I ran 27/64 gearing, but 27/81 is going to be incredibly slow
@CD02 said he was maxed out whatever that means. Already using the largest pinion??‍♂️
He was considering a smaller spur gear at this point.
But, I feel he needs to run the 2600kv on 3S or get a 4200kv motor that translates with the stock gearing and the stock brushed 12T motor much better.
His gearing is just maxxed out and he lost most of his top end with the 2600kv running 2S. :cool:
Yeah, that's why I originally went with such a low KV motor. I love me some low KV high gearing setups, but unfortunately, you can't do that here. I figure the lower gearing will compensate for the low torque of the 4300KV or whatever I get, so that should be fine. I always try to aim for 40mph on 2s as a solid gearing combo. Then drop a few teeth for 3s or 4s

I also try to aim for around the same KV as the brushless variant so I can go by their gearing recommendations. Arrma makes it difficult due to different gear ratios in diffs and such
 
I put everything in the gearing calc, and it says top speed on 2s is about 20mph. Even with the BLX Gearing (diffs & spur/pinion), it was quite mild.

Check your calculator math. I just did it in my calculator using the BLX specs (57T spur + 2600kv motor + 110mm senton sized tires + 2.85 diff ratio). Here is from 15T for baseline, up to the max 26T you can fit.

15T pinion on 2s (8.4v) = 25.98 mph
15T pinion on 3s (12.6v) = 38.97 mph

26T pinion on 2s (8.4v) = 45.04 mph
26T pinion on 3s (12.6v) = 67.55 mph
 
Check your calculator math. I just did it in my calculator using the BLX specs (57T spur + 2600kv motor + 110mm senton sized tires + 2.85 diff ratio). Here is from 15T for baseline, up to the max 26T you can fit.

15T pinion on 2s (8.4v) = 25.98 mph
15T pinion on 3s (12.6v) = 38.97 mph

26T pinion on 2s (8.4v) = 45.04 mph
26T pinion on 3s (12.6v) = 67.55 mph
My calculations atm are with the mega gearing and tires. Different ratios and OD as the BLX (not sure about tires)
 
My calculations atm are with the mega gearing and tires. Different ratios and OD as the BLX (not sure about tires)
Mega diff ratio is almost the same (2.88) so the big difference is the mega 48p spur (91T) which yeah I can see why you are bummed out, my math came out to 27mph using stock mega spur/diffs/and 48p 27T. But you said earlier that even with BLX gearing speed wasn't great but math at least says otherwise.
 
The Arrma 3S BLX motor mount only goes up to a 26t and the Mega motor mount only does 26t. There is no way for me to possibly go further up on the pinion. On my previous basher, it was fine since I ran 27/64 gearing, but 27/81 is going to be incredibly slow
I would have expected the 26t to do fine, just as @suchtragedy 's math seems to indicate.
You can also get an adjustable motor mount for free choice of pinions. I think that would be a more sensible route. A 4300kv motor feels like a downgrade.
 
What could I be doing wrong here? I've plugged in other RC's and this has been quite accurate

(bolospeed_rc_calculator) Senton MEGA  -  Compatibility Mode - Excel 9_2_2020 8_12_05 AM.png

This is the BLX gearing

(bolospeed_rc_calculator) Senton  -  Compatibility Mode - Excel 9_2_2020 8_15_28 AM.png

Mega diff ratio is almost the same (2.88) so the big difference is the mega 48p spur (91T) which yeah I can see why you are bummed out, my math came out to 27mph using stock mega spur/diffs/and 48p 27T. But you said earlier that even with BLX gearing speed wasn't great but math at least says otherwise.
I feel like this would be a lot okayer with MT tires from the granite or something, but they should have used a far smaller spur for the Senton. I'd love to see how you calculated the setup on your end, I must be plugging something in wrong
 
Last edited:
Maybe "maxed out" in terms of Arrma pinions? But any 5mm mod .8 pinion should do the job, right?
I would prefer staying with the lower kv motor.
I agree. But 2600kv may be a tad too low IMHO.
Somewhere around 3500kv in a 36xx motor Can seems like a good place to start if you can source one. Higher kv brings brings heat to an uncontrollable point if you are looking for speed and the gearing that's required for it. :unsure:
 
I agree. But 2600kv may be a tad too low IMHO.
Somewhere around 3500kv in a 36xx motor Can seems like a good place to start if you can source one. Higher kv brings brings heat to an uncontrollable point if you are looking for speed and the gearing that's required for it. :unsure:
I think I'm going to just go with a 3300 since that's the BLX motor specs. That way I can run the recommended gearing while I slowly convert the drivetrain. I was mostly worried about it being fast enough with the 27/81 setup, then gear down when I buy the 57t spur

It looks pretty good calculated with 3300kv, 20/57 gearing, and Mega diffs. Possibly bump up to a 23 or 24 if I get the adjustable motor mount.
 
Yeah 3300kv seems about right IMO. I said 3500 as a range, give or take. The BLX 3300 appears dead on. More flexibility gearing wise. :cool:
 
Yeah 3300kv seems about right IMO. I said 3500 as a range, give or take. The BLX 3300 appears dead on. More flexibility gearing wise. :cool:
Cool cool, thanks for the help. I've been looking around for the entire slipper unit to just drop in, and boy are they pricey! I'm wondering if building part by part individually would be cheaper ?
 
Probably not cheaper part by part...usually. But sometimes you don't have a choice. And you need the whole unit anyway. :cool:
 
Old Thread: Hello . There have been no replies in this thread for 90 days.
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.
Back
Top