When do you switch to FULL Synthetic Motor Oil ???
Outstanding HDF Member
Joined: Oct 2009
Posts: 2,791
Likes: 690
From: Smalltown,USA
Well the only time I've seen the cranks bearing fail was on higher performance motor where the crank spread.. Only reason it failed was the edge of the bearing dug into the race due to misalignment (pre 03 motor) . I've seen a bearing walk out of the case due to spread crank also tho the bearing still looked good.
I do wonder what the wrong oil can do for lifter life.. Lifter piston fit in body.. I've seen crappy oil blue stain piston pins and rocker shafts / rockers.
If you lose a roller on a lifter, was it lubrication or the lifter? Good thing is that the cam base circle on M8s are much bigger than TC which spins the roller fast but takes side load off the lifter and cam.
I do wonder what the wrong oil can do for lifter life.. Lifter piston fit in body.. I've seen crappy oil blue stain piston pins and rocker shafts / rockers.
If you lose a roller on a lifter, was it lubrication or the lifter? Good thing is that the cam base circle on M8s are much bigger than TC which spins the roller fast but takes side load off the lifter and cam.
I think this is causing the metal to color and cause heat dissipation problems.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,830
Likes: 7,968
From: poway
Synthetics are definitely the way to go.. They handle heat much better than any dino..
Outstanding HDF Member
Joined: Oct 2009
Posts: 2,791
Likes: 690
From: Smalltown,USA
Just took apart a 110 with 45,000 miles with lifter failure and the piston skirts have a blue color. Failure has to be to much spring rate. But the blueing has to be a lean condition. I'm really not sure.
Seasoned HDF Member
Joined: Jan 2008
Posts: 13,593
Likes: 11,289
From: State of Confusion
One point is that the bike bluing parts was not an HD.. It was a Circa 76 baja race bike.. The issue was with the motor running 2 different types of Dino. One brand oil worked well the other had issues. The results occurred twice not just once..
Synthetics are definitely the way to go.. They handle heat much better than any dino..
Synthetics are definitely the way to go.. They handle heat much better than any dino..
Last edited by mjwebb; Jan 13, 2017 at 05:40 PM.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,830
Likes: 7,968
From: poway
I'm sticking with HD360 on my M8, like all the Harleys I've owned. This M8 is the first one that has not shown any exhaust discoloration. They did say the exhaust gas temps have been lowered by 100 degrees. But since the oil will run thru the cooling passages in the heads I added the fan assisted oil cooler. I'll definitely put the bike thru some torturous heat trips this Summer, like always and never experienced oil related failures. Hell my Heritage didn't even have an oil cooler and I rode that hard in high heat. Synthetic handles heat better and cold weather starts, only a fool would debate that, but also think a good conventional / petroleum based oil with an add pack designed to handle heat is fine and just change it regularly. Synthetic for a lot of applications is like using a stick of dynamite when an M80 will do. Now if they were priced similarly I might reconsider but I prefer a quality conventional oil in a non heavily modified engine for a Touring bike and just keep the fluid and filter fresh
The synthetic I use is cheaper than HD 360. See you can have you cake and eat it too..
Run M1 automotive from Wallyworld. I'd been using 10w40 GTX in the primaries but Comps have only been lasting about 20-30K in my EGC.. Pre 6 speeds comps like it tho.. Thinking Rotella oil 15w40.. Run Valvoline semi syn in the tranny. I have blown the trap door bearings on one bike (125 hp)at 40K but other that that no problems.
Again use what you want.. On more thing.. I hate oil threads.. I've bet I've pissed more people off on oil threads then anyone and could really give a frying fork about them..
Seasoned HDF Member
Joined: Jan 2008
Posts: 13,593
Likes: 11,289
From: State of Confusion
Hey use whatever you like.. Getting HD 360, gets you down to the dealer to talk to the guys.. Besides it don't sound like you put on many miles before trading the bike in and don't take the motor apart..
The synthetic I use is cheaper than HD 360. See you can have you cake and eat it too.. Run M1 automotive from Wallyworld. I'd been using 10w40 GTX in the primaries but Comps have only been lasting about 20-30K in my EGC.. Pre 6 speeds comps like it tho.. Thinking Rotella oil 15w40..
Run Valvoline semi syn in the tranny. I have blown the trap door bearings on one bike (125 hp)at 40K but other that that no problems.
Again use what you want.. On more thing.. I hate oil threads.. I've bet I've pissed more people off on oil threads then anyone and could really give a frying fork about them..
The synthetic I use is cheaper than HD 360. See you can have you cake and eat it too..
Run M1 automotive from Wallyworld. I'd been using 10w40 GTX in the primaries but Comps have only been lasting about 20-30K in my EGC.. Pre 6 speeds comps like it tho.. Thinking Rotella oil 15w40.. Run Valvoline semi syn in the tranny. I have blown the trap door bearings on one bike (125 hp)at 40K but other that that no problems.
Again use what you want.. On more thing.. I hate oil threads.. I've bet I've pissed more people off on oil threads then anyone and could really give a frying fork about them..
"I've bet I've pissed more people off on oil threads" ah c'mon now, give yourself some credit..not just oil threads
yeah, I don't keep a bike forever but do run them hard...my taking motors apart days went away with my motocross and muscle car years..but at least we agree on Rotella T 15W40..that's the only oil I used in my 383 anyway..I've had so many bikes, cars and boats and now that I'm older just want to ride and not work on stuff..been there done all that for decades..I'll just wait for your response telling me again how little I know and how much you do
Last edited by mjwebb; Jan 13, 2017 at 11:31 PM.
Road Warrior
Joined: Sep 2016
Posts: 1,395
Likes: 364
From: Okmulgee
"Getting HD 360, gets you down to the dealer to talk to the guys." WTF does that mean, you have no idea wtf you're talking about...we avg easy over 15K a year touring with our Chapter friends going all over the place, a lot of them with older high mileage bikes that don't run synthetic and have never had to tear them apart, get a grip
"I've bet I've pissed more people off on oil threads" bet more than just oil threads
yeah, I don't keep a bike forever but do run them hard...my taking motors apart days went away with my motocross and muscle car years..but at least we agree on Rotella T 15W40..that's the only oil I used in my 383 anyway..I've had so many bikes, cars and boats and now that I'm older just want to ride and not work on stuff..been there done all that for decades
"I've bet I've pissed more people off on oil threads" bet more than just oil threads
yeah, I don't keep a bike forever but do run them hard...my taking motors apart days went away with my motocross and muscle car years..but at least we agree on Rotella T 15W40..that's the only oil I used in my 383 anyway..I've had so many bikes, cars and boats and now that I'm older just want to ride and not work on stuff..been there done all that for decades
The little Yamahammer mono. The RM,,, that was a beast bike back then. Then Honda,,, I had pretty much walked away from them buy then. But I still own my old 50 Mini Trail. Back in the 70's I would buy those type motorcross bikes and turn them into super moto bikes, regester them and put them on the street.Brings back my heros, Hanah, Decoster, Roberts. Thanks for the pics.
now go by some Amsoil. lolololololol
Thanks
Seasoned HDF Member
Joined: Jan 2008
Posts: 13,593
Likes: 11,289
From: State of Confusion
Thanks for the pics. I'm still a oil snob. Nice old Charger. I was a Cude and Challenger Mopar man. Hell Mopar Hemi's and a 383 made my RK a reality. And the bikes. I'm a old school 2 stroke guy. When I sold my Mopars. I also sold my RZ350 and 500 rocket bikes. I had to slow down. I'm 55 and have never broken a bone in a car or on a bike. I'm on borrowed time. I've had nightmares since buying my RK that it will fall on me and break my hip over a parking drop or some stupid BS.
The little Yamahammer mono. The RM,,, that was a beast bike back then. Then Honda,,, I had pretty much walked away from them buy then. But I still own my old 50 Mini Trail. Back in the 70's I would buy those type motorcross bikes and turn them into super moto bikes, regester them and put them on the street.Brings back my heros, Hanah, Decoster, Roberts. Thanks for the pics.
now go by some Amsoil. lolololololol Thanks
The little Yamahammer mono. The RM,,, that was a beast bike back then. Then Honda,,, I had pretty much walked away from them buy then. But I still own my old 50 Mini Trail. Back in the 70's I would buy those type motorcross bikes and turn them into super moto bikes, regester them and put them on the street.Brings back my heros, Hanah, Decoster, Roberts. Thanks for the pics.
now go by some Amsoil. lolololololol
ThanksLast edited by mjwebb; Jan 13, 2017 at 11:47 PM.
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Seasoned HDF Member
Joined: Oct 2014
Posts: 5,004
Likes: 2,329
From: Camp Lejeune, NC
Hey use whatever you like.. Getting HD 360, gets you down to the dealer to talk to the guys.. Besides it don't sound like you put on many miles before trading the bike in and don't take the motor apart..
The synthetic I use is cheaper than HD 360. See you can have you cake and eat it too.. Run M1 automotive from Wallyworld. I'd been using 10w40 GTX in the primaries but Comps have only been lasting about 20-30K in my EGC.. Pre 6 speeds comps like it tho.. Thinking Rotella oil 15w40..
Run Valvoline semi syn in the tranny. I have blown the trap door bearings on one bike (125 hp)at 40K but other that that no problems.
Again use what you want.. On more thing.. I hate oil threads.. I've bet I've pissed more people off on oil threads then anyone and could really give a frying fork about them..
The synthetic I use is cheaper than HD 360. See you can have you cake and eat it too..
Run M1 automotive from Wallyworld. I'd been using 10w40 GTX in the primaries but Comps have only been lasting about 20-30K in my EGC.. Pre 6 speeds comps like it tho.. Thinking Rotella oil 15w40..Run Valvoline semi syn in the tranny. I have blown the trap door bearings on one bike (125 hp)at 40K but other that that no problems.
Again use what you want.. On more thing.. I hate oil threads.. I've bet I've pissed more people off on oil threads then anyone and could really give a frying fork about them..
Novice
Joined: Dec 2016
Posts: 16
Likes: 2
From: Pensacola, Florida
Lower ZDDP in engine lubricants only affected high pressure cam shaft/lifter applications from the Flat Tappet muscle car era. Newer overhead cam technology wasn't impacted. During my studies on Ford's DOHC modular engines, a lubricant with higher ZDDP didn't reduce wear metals in oil analysis when compared to a lubricant from the API SM or SN reformulation (reduced ZDDP), assuming it was a top tier lubricant.
I too was once an advocate for high levels of ZDDP. Not anymore. Top tier blends have compensated with other anti-wear additives that were not catalytic poisoning, yet kept things in check.
I too was once an advocate for high levels of ZDDP. Not anymore. Top tier blends have compensated with other anti-wear additives that were not catalytic poisoning, yet kept things in check.