Using gear oil for fork oil!?!?

Thebrozzanator · 02-19-2021, 03:01 PM

So I was doing some research about fork oil. Someone recommended using gear oil. This is for my Kp mini. 85w/140 was the recommendation. Could I use the same gear oil for my Brozz fork oil change too? As in is it ok and a good weight? Thanks

wheelbender6 · 02-19-2021, 03:04 PM

Hmm. Fork oil is around 5w. Gear oil is usually at least 85w. Haven't tried gear oil in the fork, but is sounds a bit too thick.

david3921 · 02-19-2021, 03:37 PM

Use ATF. Check this thread from Spud.

http://www.chinariders.net/showthrea...t=chart&page=2

Reading the chart at post #27, you can see how different weights of fork oil compare to ATF. For an example, Spud was looking for a 10w equivalent in ATF and found Mobil 1 Synthetic.

mtiberio · 02-19-2021, 03:55 PM

God no! Use ATF in a pinch. Even that heavy at 7.5 wt.

Megadan · 02-19-2021, 04:21 PM

Riding like your forks are made out of rocks aside, too high of an oil viscosity will start to put a lot of pressure on the fork seals and could potentially blow them out. Just stick to fork oil.

Fork oil and ATF both contain high levels of anti foaming agents, something that suspension oil needs in order to properly function without losing damping ability. Gear oil is engineered for compression and and shearing resistance.

If you really want to experiment with heavier fork oil, they make it up to 30W.

OneLeggedRider · 02-20-2021, 08:54 AM

Question, does your Brozz have USD forks? Either way you don't want anything heavier than 15w, and 7.5w will perform best. When I did mine I bought Polaris/Victory 7.5w fork oil for the low low price of $16 a quart. When we did Jay's Hawk we bought off-brand ATF for $3.75 a quart and it performed exactly the same as far as compression and rebound. The only difference is ATF is red and Polaris likes all of their oils to be blue to let you know they're "really performing"..

(And so they can void your warranty if the oil isn't blue..)

tknj99 · 02-20-2021, 09:04 AM

I used 15W Maxima Fork Oil in my Brozz and it has worked out great.. reduced the front end bottoming out from often to rarely now.

02-19-2021, 03:01 PM	#1
Thebrozzanator Join Date: Aug 2019 Posts: 130	Using gear oil for fork oil!?!? So I was doing some research about fork oil. Someone recommended using gear oil. This is for my Kp mini. 85w/140 was the recommendation. Could I use the same gear oil for my Brozz fork oil change too? As in is it ok and a good weight? Thanks
	0

02-19-2021, 03:37 PM	#3
david3921 Join Date: Feb 2009 Location: Michigan Posts: 1,030	Use ATF. Check this thread from Spud. http://www.chinariders.net/showthrea...t=chart&page=2 Reading the chart at post #27, you can see how different weights of fork oil compare to ATF. For an example, Spud was looking for a 10w equivalent in ATF and found Mobil 1 Synthetic. __________________ 2012 Kawasaki Versys 1984 Honda Magna V65 2016 Rhino 250 2016 Tao Tao 125D
	2

02-19-2021, 03:55 PM	#4
mtiberio Join Date: Jun 2016 Location: Arlington, VA Posts: 258	God no! Use ATF in a pinch. Even that heavy at 7.5 wt. __________________ 4 time WERA SuperVintage Roadracing National Champion, SCTA Land Speed Record Holder, 3rd AMA Motorcycle GP of Miami
	2

02-19-2021, 04:21 PM	#5
Megadan Join Date: Apr 2017 Location: Omaha, NE Posts: 7,986	Riding like your forks are made out of rocks aside, too high of an oil viscosity will start to put a lot of pressure on the fork seals and could potentially blow them out. Just stick to fork oil. Fork oil and ATF both contain high levels of anti foaming agents, something that suspension oil needs in order to properly function without losing damping ability. Gear oil is engineered for compression and and shearing resistance. If you really want to experiment with heavier fork oil, they make it up to 30W. __________________ Hawk Information and Resource guide: http://www.chinariders.net/showthread.php?t=20331 2018 Hawk 250 - Full Mod list here. http://www.chinariders.net/showpost....62&postcount=1 2024 Royal Enfield Shotgun 650 https://chinariders.net/showthread.php?t=34124
	2

02-20-2021, 08:54 AM	#6
OneLeggedRider Join Date: Nov 2018 Location: Stockport, Oh. Posts: 1,442	Question, does your Brozz have USD forks? Either way you don't want anything heavier than 15w, and 7.5w will perform best. When I did mine I bought Polaris/Victory 7.5w fork oil for the low low price of $16 a quart. When we did Jay's Hawk we bought off-brand ATF for $3.75 a quart and it performed exactly the same as far as compression and rebound. The only difference is ATF is red and Polaris likes all of their oils to be blue to let you know they're "really performing".. (And so they can void your warranty if the oil isn't blue..) __________________ ~ Don't poke the bear ~ M.M.I. Dean's List graduate class of '95 and Specialty welder 2020 Ice Bear Terifecta 150cc Trike 2011 Honda Foreman 500ES 4x4 2001 Polaris Scrambler 400
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02-19-2021, 03:04 PM	#2
wheelbender6 Join Date: May 2015 Location: Houston area Posts: 1,902	Hmm. Fork oil is around 5w. Gear oil is usually at least 85w. Haven't tried gear oil in the fork, but is sounds a bit too thick. __________________ "Its not WHAT you ride; its THAT you ride"
	3

02-20-2021, 09:04 AM	#7
tknj99 Join Date: Oct 2020 Location: Central VA Posts: 1,254	I used 15W Maxima Fork Oil in my Brozz and it has worked out great.. reduced the front end bottoming out from often to rarely now. __________________ 2024 Zuma Storm 150 DLX 2019 Beta 430 RRS 2017 Honda Fury Former China Bikes: Tao DBX1, Brozz 250, CSC RX4, Titan DLX, Templar X
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