M8 problems
Road Warrior
Joined: Apr 2017
Posts: 1,451
Likes: 230
From: United States
Reader beware of fake news 90% of the problem comments are posted by trolls. Prior to posting about your problem M8; lets see a copy of your title or registration. I bet we see very few postings. I bought an m8 in April, I ride it every day to work, yes in NY where its cold. The ONLY problem I have experienced is that I have to stop for gas every 220 miles.
Really, group I ride with out last spring had his M8 on the back of a flat bed after 50 miles and just after his 1000 mile service.As much M8 owners hate to acknowledge this, The M8 aint as good as it should be and Harleys got a real problem on their hands and are struggling with a fix 3 oil pump designs in.Wiz
Novice
Joined: Jan 2016
Posts: 18
Likes: 2
From: USA
I want to chime in on this, so far I have had the exhaust crossover pipe clamp all the way loose from 0 miles on the bike, didnt discover untill I got home from dealer 620 miles away. then checked trans oil and was 5 ounces light. checked primary and was 5 ounces over full. called dealer and they put orange dye in and told me to drive bike for 1000 miles, (kind of hard in winter in the Northwest) so far 500 miles on since dye and no transfer) odd. Was thinking maybe the factory built the bike on Friday at quitting time.
Heard an odd chirping sound next, 2 things came to mind, blown head gasket or loose spark plug, two outer plugs were a little loose so i popped the tank off and checked the other ones that you cant get to very easily, they were not even screwed in all the way. . checked the exhaust header to cylinder clamps and they were so loose I am sure the gaskets were not sealing as i could hear a tick tick at the clamp and then gone after tightening. I actually rented a video of the production line at Harley from Amazon and those workers look like they are running after the bikes on the line trying to keep up with production line speed. Last thing that kind of left me with a cold feeling in the pit of my stomach is I met a local rider at a dealer near me with a Milwaukee 8 Road King, he has 40,000 miles on the bike, I asked him if he had any issues. 3 sets of wheel bearings, front and back, 3 clutch switches and 2nd engine due to sumping issue.
Heard an odd chirping sound next, 2 things came to mind, blown head gasket or loose spark plug, two outer plugs were a little loose so i popped the tank off and checked the other ones that you cant get to very easily, they were not even screwed in all the way. . checked the exhaust header to cylinder clamps and they were so loose I am sure the gaskets were not sealing as i could hear a tick tick at the clamp and then gone after tightening. I actually rented a video of the production line at Harley from Amazon and those workers look like they are running after the bikes on the line trying to keep up with production line speed. Last thing that kind of left me with a cold feeling in the pit of my stomach is I met a local rider at a dealer near me with a Milwaukee 8 Road King, he has 40,000 miles on the bike, I asked him if he had any issues. 3 sets of wheel bearings, front and back, 3 clutch switches and 2nd engine due to sumping issue.
Road Warrior
Joined: Apr 2017
Posts: 1,451
Likes: 230
From: United States
I want to chime in on this, so far I have had the exhaust crossover pipe clamp all the way loose from 0 miles on the bike, didnt discover untill I got home from dealer 620 miles away. then checked trans oil and was 5 ounces light. checked primary and was 5 ounces over full. called dealer and they put orange dye in and told me to drive bike for 1000 miles, (kind of hard in winter in the Northwest) so far 500 miles on since dye and no transfer) odd. Was thinking maybe the factory built the bike on Friday at quitting time.
Heard an odd chirping sound next, 2 things came to mind, blown head gasket or loose spark plug, two outer plugs were a little loose so i popped the tank off and checked the other ones that you cant get to very easily, they were not even screwed in all the way. . checked the exhaust header to cylinder clamps and they were so loose I am sure the gaskets were not sealing as i could hear a tick tick at the clamp and then gone after tightening. I actually rented a video of the production line at Harley from Amazon and those workers look like they are running after the bikes on the line trying to keep up with production line speed. Last thing that kind of left me with a cold feeling in the pit of my stomach is I met a local rider at a dealer near me with a Milwaukee 8 Road King, he has 40,000 miles on the bike, I asked him if he had any issues. 3 sets of wheel bearings, front and back, 3 clutch switches and 2nd engine due to sumping issue.
Heard an odd chirping sound next, 2 things came to mind, blown head gasket or loose spark plug, two outer plugs were a little loose so i popped the tank off and checked the other ones that you cant get to very easily, they were not even screwed in all the way. . checked the exhaust header to cylinder clamps and they were so loose I am sure the gaskets were not sealing as i could hear a tick tick at the clamp and then gone after tightening. I actually rented a video of the production line at Harley from Amazon and those workers look like they are running after the bikes on the line trying to keep up with production line speed. Last thing that kind of left me with a cold feeling in the pit of my stomach is I met a local rider at a dealer near me with a Milwaukee 8 Road King, he has 40,000 miles on the bike, I asked him if he had any issues. 3 sets of wheel bearings, front and back, 3 clutch switches and 2nd engine due to sumping issue.
Sounds just like the same people that built my sporty. All I got was attitude from the guys behind the service desk when I said I didnt expect any problems on a brand new bike,Last time they see my dime Wiz😡
Last edited by Wizardofaus; Jan 2, 2018 at 10:23 PM.
Ultimate HDF Member
Joined: Jul 2014
Posts: 5,649
Likes: 430
From: MASS_hole
I want to chime in on this, so far I have had the exhaust crossover pipe clamp all the way loose from 0 miles on the bike, didnt discover untill I got home from dealer 620 miles away. then checked trans oil and was 5 ounces light. checked primary and was 5 ounces over full. called dealer and they put orange dye in and told me to drive bike for 1000 miles, (kind of hard in winter in the Northwest) so far 500 miles on since dye and no transfer) odd. Was thinking maybe the factory built the bike on Friday at quitting time.
Heard an odd chirping sound next, 2 things came to mind, blown head gasket or loose spark plug, two outer plugs were a little loose so i popped the tank off and checked the other ones that you cant get to very easily, they were not even screwed in all the way. . checked the exhaust header to cylinder clamps and they were so loose I am sure the gaskets were not sealing as i could hear a tick tick at the clamp and then gone after tightening. I actually rented a video of the production line at Harley from Amazon and those workers look like they are running after the bikes on the line trying to keep up with production line speed. Last thing that kind of left me with a cold feeling in the pit of my stomach is I met a local rider at a dealer near me with a Milwaukee 8 Road King, he has 40,000 miles on the bike, I asked him if he had any issues. 3 sets of wheel bearings, front and back, 3 clutch switches and 2nd engine due to sumping issue.
Heard an odd chirping sound next, 2 things came to mind, blown head gasket or loose spark plug, two outer plugs were a little loose so i popped the tank off and checked the other ones that you cant get to very easily, they were not even screwed in all the way. . checked the exhaust header to cylinder clamps and they were so loose I am sure the gaskets were not sealing as i could hear a tick tick at the clamp and then gone after tightening. I actually rented a video of the production line at Harley from Amazon and those workers look like they are running after the bikes on the line trying to keep up with production line speed. Last thing that kind of left me with a cold feeling in the pit of my stomach is I met a local rider at a dealer near me with a Milwaukee 8 Road King, he has 40,000 miles on the bike, I asked him if he had any issues. 3 sets of wheel bearings, front and back, 3 clutch switches and 2nd engine due to sumping issue.
Novice
Joined: Jun 2017
Posts: 22
Likes: 9
From: The Holler
Dealer called today.
Dealer asked if I had experienced any problems with, violent engine braking when down shifting or any loss of power or sluggish power. My bike is 2017 Road King (build date March 2017) and Ive had no problems to date but I travel a lot for work and only have 1250 miles on it since May 20, 2017 when I brought it home.
After some persistence, my dealer told me they had received a new service bulletin with regard to oil sumping. He said essentially, some bikes have experienced problems where the lower end fills up with too much oil increasing drag on the crank. He said he just wanted to check with me and if I have problems they would come pick my bike up and deliver back to me after repairs. (3.5 hour drive one way) He made it sound like theres a new upgraded oil pump available but unless I have problems it would cost me.
Keep in mind this is what I could drag out of him. As of now there is NO recall, just a service bulletin.
Keep in mind this is what I could drag out of him. As of now there is NO recall, just a service bulletin.
Advanced
Joined: Nov 2017
Posts: 54
Likes: 7
From: Gods country
Clutch switch issues seem to be pretty common .
Some of the guys I ride with that are on 14s and newer have just about all had the issue of not being able to start it in gear. So I know that’s not something new to the M8. It seams to be intermittent though on some of them.
Some of the guys I ride with that are on 14s and newer have just about all had the issue of not being able to start it in gear. So I know that’s not something new to the M8. It seams to be intermittent though on some of them.
Cruiser
Joined: Aug 2017
Posts: 107
Likes: 13
From: New England
Really, group I ride with out last spring had his M8 on the back of a flat bed after 50 miles and just after his 1000 mile service.As much M8 owners hate to acknowledge this, The M8 aint as good as it should be and Harleys got a real problem on their hands and are struggling with a fix 3 oil pump designs in.Wiz
Absolutely inexcusable! The M8 should be FLAWLESS, especially with the various problems the Twin Cam had. It should be "put gas in and ride" for 100,000 miles or more!
Yep, this is why I bought a Sportster...after 30 years, the 4-cam Evo is pretty much sorted out.
Clutch switch issues seem to be pretty common .
Some of the guys I ride with that are on 14s and newer have just about all had the issue of not being able to start it in gear. So I know thats not something new to the M8. It seams to be intermittent though on some of them.
Some of the guys I ride with that are on 14s and newer have just about all had the issue of not being able to start it in gear. So I know thats not something new to the M8. It seams to be intermittent though on some of them.
Last edited by ChickinOnaChain; Jan 14, 2018 at 08:57 AM.
1st Gear
Joined: Jan 2018
Posts: 5
Likes: 13
From: Texas
M8 Stage IV Sumping and Power problems
I bought my 2018 RGS new in November. I had the Stage IV installed at 1000mi. The motor started making knocking noises, brought it to my dealer and the told me the pistons were not getting any oil and the motor would be replaced. After waiting 3-weeks I got a new Stage IV installed. Within 100 miles it started loosing power, engine braking and running hot. Towed it into the dealer and they said my oil pump needs replacement. Is my new motor damaged too. Anyone have some advice?
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Tourer
Joined: Apr 2017
Posts: 349
Likes: 59
From: Bedford, Nova Scotia
I think that if there really are just two sides in the M8 sub-forum, then they're the people that think the fluid transfer is a design flaw and either does (or will) happen on every hydraulic clutched M8 bike HD has made, or the people that think its a manufacturing or parts defect effecting some of the hydraulic clutch bikes.
Either way the MoCo's response to the issue sucks. But there's really no way to tell from this forum which side of that divide is actually right - there's just not enough data.
The only thing the divide really effects is how one goes about troubleshooting the problem. If all you have in front of you is a bike that transfers fluid from the trans to the primary then it's easy to assume that its a design problem and start looking for things the change (or add) to the design that would eliminate the transfer.
On the other hand, if you have a bike that transfers and another one that doesn't it would be really time consuming and expensive to disassemble them and start measuring things to try and figure out what's different between the two.
Personally I would've hoped that the MoCo would've done that second step by now... but if they have maybe they did discover that it really is a design defect and they've kept their mouths shut until they really know how widespread the problem is. Or maybe they did it and found there are a number of small (and different) manufacturing defects in different bikes. This would explain why some folks have reported fixes (or just changes) to their transfer flow rates.
IMO things would be nicer here if people didn't make assumptions like "They ALL do it because I heard about 15 cases on the forum" or "They're whining just because they got a bad one" or "They probably just aren't measuring right", etc, etc, etc
Either way the MoCo's response to the issue sucks. But there's really no way to tell from this forum which side of that divide is actually right - there's just not enough data.
The only thing the divide really effects is how one goes about troubleshooting the problem. If all you have in front of you is a bike that transfers fluid from the trans to the primary then it's easy to assume that its a design problem and start looking for things the change (or add) to the design that would eliminate the transfer.
On the other hand, if you have a bike that transfers and another one that doesn't it would be really time consuming and expensive to disassemble them and start measuring things to try and figure out what's different between the two.
Personally I would've hoped that the MoCo would've done that second step by now... but if they have maybe they did discover that it really is a design defect and they've kept their mouths shut until they really know how widespread the problem is. Or maybe they did it and found there are a number of small (and different) manufacturing defects in different bikes. This would explain why some folks have reported fixes (or just changes) to their transfer flow rates.
IMO things would be nicer here if people didn't make assumptions like "They ALL do it because I heard about 15 cases on the forum" or "They're whining just because they got a bad one" or "They probably just aren't measuring right", etc, etc, etc
Club Member
Joined: Feb 2013
Posts: 9,829
Likes: 8,737
From: Edmonton, Alberta
I thought all M8's were hydraulic clutch. (Can anyone confirm?). Don't know why they went hydraulic ... I test rode several of the touring 2018's and found the clutch much harder than any other harley I have ever owned 81, 83, 92, 97, 11 ( not counting my foot clutch 43). I wish they had made that an "option"