M8 oil consumption

[Slider1950]

Well I have narrowed down the oil consumption on my 2018 Softail M8. Seems that I am using about 1/2 quart every 1,200 miles. My bike has about 3,500 miles on it now and I have been keeping a close eye on the oil consumption. So is the general consensus that 1/2 quart every 1,200 miles is excessive or not thank you?

[sandrooney]

According to Harley it's not excessive. I wouldn't like it if it were my bike.

[Oz Dan]

That's around 2 quarts between service intervals. In my bike, whilst the dipstick will drop across a service interval, I don't need to add any because the dipstick still shows oil between the acceptable range when checked hot.

I'd pay for a compression test because if your rings and valves are seated it shouldn't use that much oil.

[klammer76]

In my world that's excessive. It would drive me nuts.

[Slider1950]

Yeah I'm not happy about it either.

[jls 64]

In my world that's excessive. It would drive me nuts.

. ..!!!

[KrustyKush]

My RGU used more oil in its first 10k miles than it does now at nearly 20k miles.

During its first 2k miles I had to add oil a couple of times to get the level back to full.  I recall being surprised checking the oil after only a thousand miles and finding the level near the bottom of the stick, when I was certain it had been full before.

I always keep a very close eye on oil level, so I know exactly how much my engine is using as the oil ages.  I've seen a steady decline in oil usage as the miles have piled up.  I think these engines take a good long break-in period.  500 miles doesn't fully break the thing in.  It takes more like 5k miles.  Maybe more.  I'm not the only one to report a steady decline in oil use as the bike gets past 10k miles. 

Now, at 20k miles, my engine uses less than a quart of oil over the space of 5k miles.  I take this this to be normal.  Some folks seem to think these engines should never use any oil at all, but that doesn't feel realistic.

[rredneckn2]

The only Harley engine I have owned that used oil was a shovel. I have not owned anything pre-shovel. I have owned quite a few shovels,Evos,and several Twin Cams. Using a qt in 5k is something I have never experienced. EVERY Harley I have owned had engine upgrades done by me. If I Had a M-80 and it was using a qt @ 5k it would be coming apart. There has been numerous issues with valve seat and stem to guides. If your happy with a quart in 5000 let it be.and no it doesn't take 5 k to break in a engine.

[Slider1950]

Well I just checked the air filter and the primary oil level. The air filter is clean with only a small drop of oil. The primary level is right where I filled it to during the 1000 mile service. So my oil isn't going to either of those places.

[Hossamania]

Short rides, long interstate runs, or combo of the two?

[Slider1950]

I do a good combination of different rides.

[IronButt70]

In my world that's excessive. It would drive me nuts.

. ..!!!

Ditto. Guess I'm lucky. I never have to add oil between 5k mile oil changes on my TC.

[Oz Dan]

 My M8 will drop dipstick level to half way hot on side stand and stay there over the service interval (8000km /5000miles) just like my old TC. Lucky? I'd say it's fairly common if valves and rings are seated properly.

[coolbreeze3646]

Are you using HD synthetic or the regular dino oil?  My TriGlide seems to use more oil when I have synthetic, I have gone back to the regular stuff, less than a qt in 5,000 miles.

[Slider1950]

Are you using HD synthetic or the regular dino oil?  My TriGlide seems to use more oil when I have synthetic, I have gone back to the regular stuff, less than a qt in 5,000 miles.   

.   HD Dino.

[mac10-45]

  I feel your pain. My '17 Ultra Classic used oil between changes, 1/2 qt. or more in 2500 miles. I thought it was excessive. Dealer said unless it was more than 1 qt. in 500 miles it was not excessive per H-D. At 24,500 miles the usage had slowed to a couple of dots on the dipstick in 2,500 miles. Then, I traded it in on a '18 CVO Limited SE, 115th Anniversary, #758/1200. I was used to watching my usage so I did it on this new bike with the big bore 117" Stage 4 motor. It started varying every trip I checked the dip stick up and down. Ended up it "Sumped" at 6,700 miles. Dealer rebuilt top end (pistons, rings, jug, gaskets, etc.) oil pump was latest version. I found H-D Service Bulletin M1450 on one of these forums. My oil usage continued to fluctuate, just not as much as before. The 2019 114 & 117 motors have an "O" ring and Cover for the oil pump that's different (additional parts according to what I have read) than the previous pumps for 2017 & 2018 M8 engines. I think this is the HD fix for Sumping with Stage 3 & 4's.

At 13,599 miles my dealer installed:
25700731 GASKET SET, CAM SERVICE
62400206  OIL PUMP ASSY, COVER  (these 2 parts are on the 2019 114's and 117 inch motors)

My '18 CVO is in the shop right now and I'm having the other oil problem with M8's, oil transfer from transmission to primary. Dealer ordering vent kit and have it delivered overnight. I have about 28,000 miles on it in 15 months. They installed a Stage 2 horse power cam when the gasket and oil pump assy cover was installed ( I paid for the cam, no labor cost) cover and gasket and labor covered under warranty.

At 28,000 miles my oil usage has slowed to 2-4 dots down on the dip stick between 2,500 mile oil changes.

So, I have owned 2 M8's, both used oil, excessive for me. But, after spending $30K and $50K on new bikes, breaking them in like the dealer and the manual says I'm disappointed in the oil usage. My buddy has a '18 Ultra Limited 115th Anniversary he bought when the '18's first came out in 2017. He has over 46K miles. No oil usage but at 43K his lifters started making noise on start up. Dealer replaced lifters, push rods, oil pump (latest version) oil pump plate and gasket. Still same problem only worse. They decided the new pump was bad so new pump and Stage 2 upgrade with horsepower cam. He has now used over 1 qt of oil doing break in. He was told not to run under 3K RPM, stay in lower gears. Good Luck