2018 M8----Sumping? Failures?
Outstanding HDF Member
Joined: Oct 2016
Posts: 2,530
Likes: 546
From: Wayne County, PA
Same. Money doesnt grow on trees. Even just a 1% chance of the bike sumping made me pass on a new m8. They are probably amazing bikes but i just wont risk it. Not only that they cost alot more than other bikes in the 100hp mark ive looked at. I will always keep my evo but im a motorcyclist and i like all bike brands and types of motorcycles. And to be honest, sometimes a change in style or type of motorcycle is a good thing.
Stellar HDF Member
Joined: Sep 2009
Posts: 2,114
Likes: 666
Sumping (more oil going in than coming out and back into the tank) iseems to be caused by more causes than the usual assumed suspect...the scavenge-side o’ring in the cam chest similar to the TC issue.
Or
I have heard of out-of-round OEM cylinders that pressurized the crankcase creating turbulence that keeps the oil suspended in and on flywheels causing drag. Basically turbulence creating air in lieu of oil @ the oil pickup point at the bottom of crankcase.
Since it’s turbulent there is no rhyme or reason to when and how much it sumps...sometimes a little, sometime a lot, sometimes seems fine for miles and miles.
I’m sure it will get sorted...for Harley’s sake.
Bob
Or
I have heard of out-of-round OEM cylinders that pressurized the crankcase creating turbulence that keeps the oil suspended in and on flywheels causing drag. Basically turbulence creating air in lieu of oil @ the oil pickup point at the bottom of crankcase.
Since it’s turbulent there is no rhyme or reason to when and how much it sumps...sometimes a little, sometime a lot, sometimes seems fine for miles and miles.
I’m sure it will get sorted...for Harley’s sake.
Bob
Last edited by FLTRI17; Mar 4, 2018 at 11:52 AM.
Grand HDF Member
Joined: Nov 2017
Posts: 4,251
Likes: 3,134
From: Texas
Okay, just checking -- for some reason I thought I'd read that the out-of-round cylinders were on Stage III and Stage IV big-bore kits. Am I correct in that, or have you heard of out-of-round cylinders in stock systems?
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,922
Likes: 8,027
From: poway
It would not surprise me if there were some out of round cylinders and others with poor rings seal on marginal cylinders from a soft break in. Both could cause the issue. I have seen take off cylinders that were pretty crappy. Ring seal causing excessive carry over and sumping is a common issue in all HDs. Some are more susceptible then others.
Elite HDF Member
Joined: Jun 2007
Posts: 4,867
Likes: 268
From: People's Republic of Boulder Colorado
My '15 Limited had a few simple, easy to deal with, well-known issues. I was aware of 'em from the get-go & dealt with them the day I bought it or very shortly thereafter.
It's been smooth sailn' ever since. I do know there are a lot of ongoing gripes about the NAV & sound system(s) on the Rushmores, but since I never turn that silly-assed Boom! system on, anyway, those issues don't count (for me).
Thankfully, I bought it for the ride and mechanical reliability, not that BS gadget!In all fairness, I have to say that the system in my '17 Toyota is just as weird and "glitchy" as the ones on these bikes, if not more so. My "fix" was the same for it, too - find out how to turn it off, and do so!
Keep the rubber down,
JP
Tourer
Joined: Jul 2017
Posts: 259
Likes: 85
From: Tennessee
No problems
Purchased one of the first 17 Street Glides and eventually traded it for an 18 Anniversary Edition Street Glide. Both M8 engines performed flawlessly. The first had the SE Slip-ons, SE air cleaner and Street Tuner. The second only the SE Slip on's Could not be happier. Also, kind of amazed at the amount of "new members" that stop in and take the time to complain. Hmmmm
Ride safe
Ride safe
Outstanding HDF Member
Joined: Oct 2009
Posts: 2,791
Likes: 690
From: Smalltown,USA
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1st Gear
Joined: Jan 2018
Posts: 5
Likes: 13
From: Texas
M8 Stage IV
i bought my Stage IV to ride the crap out of it. I paid an extra $9k for this set up and Ill be dammed if Im not going to tach it out to the factory 6600 redline.
If if you bought a Dodge Demon and the dealer told you done tach it out over 5000 RPMs would you put up with it?
HD is letting customers who pay for high performance engines down. This is something I will not accept. I refuse to baby this engine just to keep it from blowing up. Thats what I paid for and I expect perfection for the extra money I spent. Not going over 5000 RPM just to keep the engine alive is a band aid.
If if you bought a Dodge Demon and the dealer told you done tach it out over 5000 RPMs would you put up with it?
HD is letting customers who pay for high performance engines down. This is something I will not accept. I refuse to baby this engine just to keep it from blowing up. Thats what I paid for and I expect perfection for the extra money I spent. Not going over 5000 RPM just to keep the engine alive is a band aid.
1st Gear
Joined: Jan 2018
Posts: 5
Likes: 13
From: Texas
M8 Stage IV
i bought my Stage IV to ride the crap out of it. I paid an extra $9k for this set up and Ill be dammed if Im not going to tach it out to the factory 6600 redline.
If if you bought a Dodge Demon and the dealer told you done tach it out over 5000 RPMs would you put up with it?
HD is letting customers who pay for high performance engines down. This is something I will not accept. I refuse to baby this engine just to keep it from blowing up. Thats what I paid for and I expect perfection for the extra money I spent. Not going over 5000 RPM just to keep the engine alive is a band aid.
If if you bought a Dodge Demon and the dealer told you done tach it out over 5000 RPMs would you put up with it?
HD is letting customers who pay for high performance engines down. This is something I will not accept. I refuse to baby this engine just to keep it from blowing up. Thats what I paid for and I expect perfection for the extra money I spent. Not going over 5000 RPM just to keep the engine alive is a band aid.