Low/no power from dead stop

[Ericehess]

So I upgraded a Wltoy 12428 rock crawler to brushless motor with GoolRc 60A esc. When I give it throttle from a dead stop on flat ground or downhill it will move very slowly with no power for a second then take off once it gets rolling. If I try to start on a slight uphill grade it will not move at all..just rocks a little and can't get going. If I nudge it it takes off fine. I have tried increasing the throttle power and have the same issues even at max. Any ideas anyone?

 

[tntpoof]

pinion gear is to large to many teeth. it also could be battery..age and type of battery?.C rating?

 

[Ericehess]

Pinion gear is 17T (32p) spur is 62T. Batteries are brand new 2S lipo..one is 25c and one is 50c..have issue with both..50c seems a bit better. The pinion and spur are metal upgrades of the stock versions.
I guess I could get a 100c battery and try that.

 

[tntpoof]

drop pinion to 14 tooth try that . dont run longer than 1 minute..motor turn?.mah of batteries?

 

[Ericehess]

To lower tooth count of pinion and keep the same spur gear I would have to get a smaller diameter pinion gear to maintain 32p ratio..in which case I would have to move motor over slightly. That could be tricky..my mount isnt adjustable. The 25c battery is 2700mah and 50c battery is 5200mah. I will look into new adjustable mount and 14t pinion thanks.

 

[Ericehess]

I found a set of 32p opinions from 12 to 16t and an adjustable mount. Should be here in a couple weeks. Will let you know if it works. Feel like I'm always waiting for parts. Been a fun project..car rips..40+mph..hope this doesn't slow it down too much.

 

[Ericehess]

Is it possible the pinion is meshed too tight with the spur gear? Switched from a 540 brushed to a 3650 (4300kv) brushless motor, that shouldn't change the alignment though. The mesh seemed ok..but if it were too tight that would cause it to bog down at low rpms right? In which case I need the adjustable mount anyway.

 

[tntpoof]

to tight of a mesh would give issues.. ..see thats why I have a Dremel tool with many bits.... I use the 2 piece of paper to adjust mesh...

 

[Ericehess]

I know the gears should be close enough to hold the paper but loose enough to be able to pull the paper out. When I get the adjustable motor mount I will adjust it accordingly. Hopefully it solves my issue. The new metal gears may have a slightly larger diameter.

 

[Ericehess]

Forgot to mention I also put big tires on it..4.5" diameter,2.5" wide. This would lower low end power too.