Challenge accepted....:mrgreen:
Last edited:
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2s or 3s for crawler?
- Thread starter champ198
- Start date
Challenge accepted....:mrgreen:
johnnyh66
Scale Detail Engineering
I raced Harley a little last weekend at the HH comp... we were just goofing around but I think I got him. ;-)
Johnnysplits
I wanna be Dave
Iv'e tried sensored and sensorless, from a 10T 3500Kv up to a 7.5T 5000Kv...even a 1600Kv outrunner 500 class heli motor! I know this motor I have coming is sensorless, but it's 1650Kv 4 pole and will take up to 6s. I'm kinda hoping that the super low gearing will get it to turn slow enough for crawling, yet be able to blast out of the hole when it's time to hang the front end high going down the street! Just like 1:1's, can't help getting wood when you witness a long, badass wheelstand from a truck!
johnnyh66
Scale Detail Engineering
hehehe
Johnnysplits
I wanna be Dave
Yeah man that's what i'm talkin' bout ^ Just needs to stay in that position a little further "thumbsup"
johnnyh66
Scale Detail Engineering
it's tough to wheelie with a drag brake. :|
Try running the motor slow on its own, and you'll find cogging even at no load!
Johnnysplits
I wanna be Dave
What motor would you recommend? Does vehicle weight play a factor in motor choice or no? Am I asking for too much (crawling ability and high speed)?
For crawling with a brushless motor having a sensored motor is mandatory!
Typical high power motors are ill fitted for crawling mainly because of their low efficiency, making them run hot and require bigger batteries, and because of their low torque.
A motor with lowish Kv (1,500-2,000) will provide useful torque at low revs and still put out lots of power if fed high voltage.
To make that power turn into high speed you need a different gearing than for crawling, so a two speed gearbox is required.
One major issue is the tires. Soft crawler foams and tires add a lot of running friction that reduce the top speed, and if you do overcome that friction they're likely to go to pieces.
So, in conclusion you can't make a truck go very fast and also crawl well at the same settings.
Typical high power motors are ill fitted for crawling mainly because of their low efficiency, making them run hot and require bigger batteries, and because of their low torque.
A motor with lowish Kv (1,500-2,000) will provide useful torque at low revs and still put out lots of power if fed high voltage.
To make that power turn into high speed you need a different gearing than for crawling, so a two speed gearbox is required.
One major issue is the tires. Soft crawler foams and tires add a lot of running friction that reduce the top speed, and if you do overcome that friction they're likely to go to pieces.
So, in conclusion you can't make a truck go very fast and also crawl well at the same settings.
