Sand slinging/Beach runs

[Mark Fradkin]

I tried out the new monster heatsink on my Quark125b w/dual 40mm fans. I was amazed how cool it ran. Perfect fit ! . Prior I was using Wond 8xl 18/51 and it would thermal after minutes. I did swap in A fiego 9xl 16/51 grears. However I did notice a big differance in speed, slower.and the additional torque seemed of little benefit. It did however run cool non stop for 25min. Hard running. Spur has washers& nut super tight no spring.
How can I achieve faster speeds again. ? remain cool Maybe put in the 8xl again. 18t pinion or 20.? Dual fans seem to have very little effect on run times. I usually just stop after 25 min to be safe.
2 speed emaxx trans
spyder 8
apachee 5s 18.5v two parallel
Paddle 40 / 23mm
New era extended chassis
6mm UE cvd w/ racer x suspension.

[captain harlock]

Since you're using the 5s lipos, just reput the 8xl and go.
Does your truck cog when it launches?

[Mark Fradkin]

NO it does not cogg.

[Tazz]

This may seem like a dumb question but why did you drop your gearing down when you went to the 9XL (18/51 to 16/51)? Shouldn't you have stayed the same or geared up?

[Mark Fradkin]

Just foolin around I have 16 18 20 pinion gears. Monster Mike suggested fiego 9xl . Sand is an enemy and an expensive$ motor could get ruined. It did run very cool w/ constant running. . I will try 18 or 20 teeth on street see what happens.

[jhautz]

whith the quark 125+heatsink I run my 9xl in my emaxx at 66/22 (3.0 gear ratio) with standard maxx diff ratio and 5.8inch tires in heavy grass fields with no heat problems. I use 66/26 (2.54 gear ratio) on pavement with 5.25" tires.

You should be able to run 18/51(2.84 gear ratio) on the beach without issue. Depending on your tire size and diff ratios. The 51/16 (3.18 ratio) is conservative IMO.

9xl is the right motor for 5s. 8xl on 5s will run hot just from the high rpm.

[coolhandcountry]

Did you try the 16 51 gearing on the 8xl?

[Mark Fradkin]

Thanks guys for the replies. I have not tried 16/51 on the 8xl yet w/new fan heatsinkset up. I plan to. But on pavement the old set of 18 or 20/51 no heatsink/ fan combo would not thermal, only in the sand, At least now Im not just breaking drivetrain parts and am able fine tune gearing. Thanks to this forum & monster store .

[coolhandcountry]

The sand has some restriction though. Make for a few higher amp draw.
Let us know how it works out.