free website stats program Mobil 1 V-Twin 20-50 in all three holes | Page 3 | Harley Davidson Forums

Mobil 1 V-Twin 20-50 in all three holes

I'll be using the V-twin in all three holes.

One thing I find interesting is that most modern vehicle manual transmission's use a motor oil not a gear oil. For example my 5 speed CRV uses a 10-40 weight motor oil. Ditto all the motorcycles that share the engine, clutch & transmission, they use a SG/MA spec motor oil.

I'm not against using a gear oil in a transmission if that is what the manufacture calls for. For example my BMW bike specifies a GL5 oil, so that's what I use.

I've never really been able to find exactly what HD recommends ( other than their own products ) but they are not exactly labelled for easy cross reference.
 
cycleman11 said:
I'll be using the V-twin in all three holes.

One thing I find interesting is that most modern vehicle manual transmission's use a motor oil not a gear oil. For example my 5 speed CRV uses a 10-40 weight motor oil. Ditto all the motorcycles that share the engine, clutch & transmission, they use a SG/MA spec motor oil.

I'm not against using a gear oil in a transmission if that is what the manufacture calls for. For example my BMW bike specifies a GL5 oil, so that's what I use.

I've never really been able to find exactly what HD recommends ( other than their own products ) but they are not exactly labelled for easy cross reference.
Click to expand...

Do yourself a favor and use a GL5 in the Harley too. The Harley gear box is a bit different than their counterparts in cars. A gear oil like Spectro GL5 will enhance the shifting of the trans dramatically over a motor oil.

Harley Davidson Community
 
Do some HD service depts offer other oil's other than HD products? Specifically the ones that are talked about on this post? I asked mine, and they said all they offer is HD...... I didn't however ask them if they would put in oil that I bring in.... Any thoughts?
 
sampson80 said:
Do some HD service depts offer other oil's other than HD products? Specifically the ones that are talked about on this post? I asked mine, and they said all they offer is HD...... I didn't however ask them if they would put in oil that I bring in.... Any thoughts?
Click to expand...

My local Harley dealer only sells HD oil, but sells Spectro trans and primary oil. Makes you think.
 
My local dealer also offers Spectro and a few others as well. Before bringing in a good oil for them to install, I would rather do it myself and know that the oil you bought found it's way into YOUR bike.:D
 
cycleman11 said:
I'll be using the V-twin in all three holes.

One thing I find interesting is that most modern vehicle manual transmission's use a motor oil not a gear oil. For example my 5 speed CRV uses a 10-40 weight motor oil. Ditto all the motorcycles that share the engine, clutch & transmission, they use a SG/MA spec motor oil.

I'm not against using a gear oil in a transmission if that is what the manufacture calls for. For example my BMW bike specifies a GL5 oil, so that's what I use.

I've never really been able to find exactly what HD recommends ( other than their own products ) but they are not exactly labelled for easy cross reference.
Click to expand...

Further update. I'm still using the Mobil 1 20-50 in the engine, but switched to Mobil 1 10-40 in the primary - resulted in better clutch action and shifting when cold. I also changed out the tranny oil - nothing on the magnet approx 4000 miles on the oil. ( Had Mobil 1 20-50 in it ) and was changing the other holes so changed the tranny as well. I put in Mobil 1 10-40 ( the mc oil ) in the tranny. The 10-40 equated to a 75-90 gear oil on the viscosity charts so the viscosity should be fine as many use a 75-90 gear oil in the 6 speed.

I'll update my results & impressions.
 
cycleman11 said:
Further update. I'm still using the Mobil 1 20-50 in the engine, but switched to Mobil 1 10-40 in the primary - resulted in better clutch action and shifting when cold. I also changed out the tranny oil - nothing on the magnet approx 4000 miles on the oil. ( Had Mobil 1 20-50 in it ) and was changing the other holes so changed the tranny as well. I put in Mobil 1 10-40 ( the mc oil ) in the tranny. The 10-40 equated to a 75-90 gear oil on the viscosity charts so the viscosity should be fine as many use a 75-90 gear oil in the 6 speed.

I'll update my results & impressions.
Click to expand...

Even IF the 10/40 equated to 75/90 gear oil as far as weight, the properties of the two are different. A gear oil has different properties and the molecules are long string molecules compared to engine oil to prevent the shearing that is common in gear environments.
This is why the Syn 3 oil from HD didn't make it as a lube in the transmission. Many cases of blued shifter forks and bearings going out at a young age because the weight of the oil was meant for engines and not transmissions.

Your trans will tell you the story after some miles but by then the wear factor has already occurred.

Primaries are much better off with a NON synthetic oil also.
 
Last edited:
What you have in the engine and primary are OK. You might want to consider a gear lube in the tranny rather than an engine oil. Something designed for the 6-speed like Mobil 1 Synthetic Gear Lubricant LS 75W-140, Spectro Heavy Duty Platinum Full Synthetic 6 speed Transmission Lube, or Redline Heavy Shockproof.

Mobil 1 Synthetic Gear Lubricant LS 75W-140
Spectro 6 Speed Transmission Lube - 6 Speed Transmission Oil - www.SpectroShop.Com
Red Line Synthetic Oil - ShockProof® Gear Oils - Heavy ShockProof®


TQ
 
I think what everyone is missing is that all GL5"s are not created equally. I know Mobil 1 doesn't recommend their GL5 for Harley transmissions but Amsoil and many others either recommend theirs saying no yellow metal corrision or just don't even address the subject. Personally,I have run both Mobil 1 and Amsoil 20/50 in all three holes with no problems, however due to all my reading on this and other sites I have changed my trans. to gear oil, now run Amsoil 20/50 in engine and primary and 75/140 in the trans. Transmission does shift better and is quieter. Don't rule out all GL5's just because some don't recommend the use of their products.
 
You must log in or register to reply here.
Back
Top