4wd gearing. Motor temp etc

[tonydevon]

What sort of motor temp is safe?

My 4wd this weekend was coming in after 5 mins with can temp of 90 to 92 degrees c

Car felt a bit soft on power.

Zero boost
Zero turbo.

Hw 2.1 esc
Orca 6.5 tx motor.

Pr SB401 buggy running 22/77 pinion and spur.

Could do with a bit more grunt from it
But with temps like that im nervous of boost or turbo.

Is it maybe time to look at a new 5.5 motor

[Hog]

Motor timing?

[tonydevon]

motor is set to as from factory, in the middle, never touched the endbell

[mattr]

What sort of final drive is it?

Might be worth experimenting with dropping one (or two) teeth from the pinion.

And checking you are getting some airflow through the shell!

[Welshy40]

Yup as per the other posts gearing, go down one and see if the punch is more and top end should be good also. The other option is a motor mounted fan, a big one. Demon racing does a few large ones and the mount is alloy as well so always a good investment as that made my Sworkz 4wd want to be pushed whereas without your wondering if its going to last

[/tobys]

+1 for motor fan. It was hot this weekend and with high grip Astro, it can push temps up - I even fitted one into my 2wd this weekend! Sounded like a hovercraft but made a massive difference in temps.

[mattr]

FWIW the 5.5 i'm running in my 4WD has almost the smallest pinion you can physically get to mesh on the stock spur (think 18 will go, i'm using 19)
and i've gone up on the spur size (from 87 to 89).

Still accelerates like a missile, and only just running out of acceleration at the end of a 20 ish metre straight. (high grip astro)

Don't use a fan on the motor, rarely tops 70. ESC tops out at about the same.

[tonydevon]

Thanks guys. Cant get a fan on the motor but will look at chassis mounted one pointed at motor.

I bought the motor used and have done 6 months racing nearly every weekend.

So the plan is. Smaller pinions. Vent the shell.
Oh and buy a 5.5

Any excuse lol.

[mattr]

Don't get a 5.5.

The only reason i've got one is as our track is 8th scale. Some of the features are a bit large!

And i had a motor lying about as well. (Came in a second hand car).

Until i put this one in i was usually running 8.5. With boost, turbo and so on on a 10th scale track (which has since been demolished). That was only giving away about a metre over the back straight against cars with 5.5/6.5 motors. But still had more to give on the boost/turbo front.

[tonydevon]

ok thanks, I guess I have nothing to lose by sorting a fan, cutting the body and running boost and turbo.

try that first

[Robocop]

You do strip and clean the motor I take it tony and put the correct amount of shims in and the motor is not binding in the can