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Using Mobil1 V-Twin in Gearbox

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Old Jan 11, 2010 | 10:12 PM
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Default Using Mobil1 V-Twin in Gearbox

Howdy All,

I know this topic has already been done many times over but please bear with me.

Lots of forums/riders and workshops recommend using Mobil1 V-Twin in all 3 holes. Even Harley recommend using their Syn3 in all 3 holes.
I am not convinced so would ike to hear from anyone who has used Mobil1 V-Twin in their gearbox and their opinion. Has anyone had any problems?

I also believe that viscosity rating of the gearbox oil isn't directly comparable to viscocity rating of the engine Oil. Thus 75w90 comparable to 10W30 engine oil. Is this correct?



Cheers

Vlad
 
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Old Jan 11, 2010 | 11:29 PM
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You can definitely use it (Mobil 1) in all three holes, but there are other better alternatives. For your transmission, you can't go wrong with "Redline V-Twin with Shockproof." I had a problem getting my bike into neutral once it reached operating temperature. Several people in this forum suggested that I try Redline trans fluid and I'm glad I did. Finding neutral is way easier now. Redline is also the oil that Baker recommends for their after market transmissions.
 
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Old Jan 12, 2010 | 12:10 AM
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Use gear oil and don't look back. I run a 75/140 and change it every 20,000 miles.
 
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Old Jan 12, 2010 | 12:25 AM
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I have also been using HD Syn 3 in all three holes. Been doing a lot of reading and research and this is the conclusion I've come to. Lots of folks use Mobil 1 or Amsoil Synthetic oil in the engine, apparently you can use conventional oil in the primary (synthetic won't hurt, just cost more) and a good sythetic gear oil in the trans. Lots use Amsoil Sever gear or Redline Heavy Shockproof gear oil.

I'm now using Mobil 1 20w50 synthetic in my engine, Redline Heavy Shockproof gear oil in the trans and Redline Primary oil in the primary.

Steve
 

Last edited by Heritage632; Jan 12, 2010 at 12:28 AM.
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Old Jan 12, 2010 | 05:59 AM
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here the poll results that was taken in here..

Tranny
https://www.hdforums.com/forum/oil-a...o-you-use.html

primary
https://www.hdforums.com/forum/oil-a...ur-choice.html

motor
https://www.hdforums.com/forum/oil-a...your-bike.html
 
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Old Jan 12, 2010 | 06:09 AM
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Originally Posted by BLKBAGGER
Use gear oil and don't look back.
+1 .
 
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Old Jan 12, 2010 | 07:09 AM
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I've used Red Line and Amsoil synthetic gear oils. Both are excellent and in particular helped shifting to nuetral.
 
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Old Jan 12, 2010 | 09:20 AM
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from what i understand the 75W90 gear oil, which is actually of equivalent viscosity to a 10W40 motor oil
 
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Old Jan 12, 2010 | 09:42 AM
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V-Twin in 2, full synth 75w-90 in tranny
 
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Old Jan 12, 2010 | 09:46 AM
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I use 85-140W by drag specilties in the trans. I had the syn3 20/50 in it and it whined a little in 5th gear. I switched it out and the trans is as quiet as can be. I use a different oil in each whole. Syn3 20/50 in engine, Drag specilties 85-140W in trans, Primary Oil for Big Twins in the Primary. I would'nt run the same oil in all the same holes in my car or truck so why should I do the same on my bike?
 

Last edited by Rockyriver; Jan 12, 2010 at 10:08 AM.
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