M8 problems
Intermediate
Joined: Jan 2014
Posts: 38
Likes: 14
From: The wrong side of SD
Overheating
I also have a 2017 Ultra Limited that developed overheating problems at about 38,000 miles. I have stock heads on top of 124 ci cylinders so was out of any type of warranty. I determined the water pump had seized so replaced along with the temp sender that is at the bottom of the left radiator. I don't think the temp sender was bad but system was drained so figured might as well replace it. Problem solved and it was an easy fix.
The pump is very easy to remove, maybe 10 min. Then remove the cover from pump and try to turn the impeller with your fingers. If you can't it is stuck. You can also plug it back into the bike and force it to run by (if I remember correctly) turning to ignition to on and pressing both turn signal switches for several seconds.
Hope this helps.
The pump is very easy to remove, maybe 10 min. Then remove the cover from pump and try to turn the impeller with your fingers. If you can't it is stuck. You can also plug it back into the bike and force it to run by (if I remember correctly) turning to ignition to on and pressing both turn signal switches for several seconds.
Hope this helps.
Stage III
Joined: Oct 2019
Posts: 3
Likes: 0
From: Delaware
sumped
I own 2019 M8 purchased 8/24/19 825miles lumped 4 quarts into crankcase. Bike has been at dealer for two weeks, I hope I'm not in the road as some the other post I've read with back and forth to dealer with this sumping issue. my bike is completely stock no MODS. not going to do any mods until issue is fixed.has anyone heard any good news with the oil pump from s&s ? thanks for feed back.
Seasoned HDF Member
Joined: Sep 2009
Posts: 17,148
Likes: 6,171
From: SE Michigan
I own 2019 M8 purchased 8/24/19 825miles lumped 4 quarts into crankcase. Bike has been at dealer for two weeks, I hope I'm not in the road as some the other post I've read with back and forth to dealer with this sumping issue. my bike is completely stock no MODS. not going to do any mods until issue is fixed.has anyone heard any good news with the oil pump from s&s ? thanks for feed back.
Seasoned HDF Member
Joined: Apr 2015
Posts: 6,863
Likes: 3,727
From: St. Charles, MO
I purchased a 2017 ultra limited with the liquid cooled M8 in November of 2016. Had Harley do a stage 3 immediately . The bike has been a pleasure to ride, not a trailer queen. NY to Sturgis, NY to Key West, NY to Daytona a few times, NY to New Orleans just to name a few. Now at almost 19,000 miles the bike is experiencing serious overheating problems and the dealer (Harley Davidson of Charlotte NC) in conjunction with Tech services in Milwaukee cant figure it out. Bike has been in for this issue 5 times in the last Month and a half. Antifreeze leaking into the combustion chamber due to hairline cracks in the cylinder walls, that was what HD told me, manufacturing defect. They cracked the rear cylinder open (literally with a sledge hammer) and replaced. Two days later the wife and I went out for an evening ride and within 15 miles or so the bike overheated. temperature and engine light on. They have the bike now, stay tuned.........
Cracks in the cylinder walls don't lead to antifreeze in the combustion chamber - cracks in the heads will.
Cracks in the cylinder walls could be caused by the overheating itself. I'd be looking at the water pump condition, as well as the AFR set by whoever did your tuning (I assume the dealership did this). One of two things is happening - either improper heating, or running too lean/hot. Maybe both.
Stage IV
Joined: Jun 2014
Posts: 4
Likes: 1
From: Florida
Anyone have a problem withe the 2020 M8 FLTRK having a high idle when it's hot? I was at Destination Daytona yesterday and the bike would idle at 1800 to 2000 rpm's when it was hot. If I slightly rolled the throttle forward it would idle correctly. The dealer said he had a few others doing the same thing but if it didn't have a dummy light on there would be no code to find out what was the cause. I started it this morning while it was cold and everything is back to normal.
Seasoned HDF Member
Joined: Sep 2009
Posts: 17,148
Likes: 6,171
From: SE Michigan
Anyone have a problem withe the 2020 M8 FLTRK having a high idle when it's hot? I was at Destination Daytona yesterday and the bike would idle at 1800 to 2000 rpm's when it was hot. If I slightly rolled the throttle forward it would idle correctly. The dealer said he had a few others doing the same thing but if it didn't have a dummy light on there would be no code to find out what was the cause. I started it this morning while it was cold and everything is back to normal.
Novice
Joined: Oct 2019
Posts: 24
Likes: 3
From: Surry VA
Clacking noise at hot idle restart
2019 Road glide 114. Bike will make a series of clacking noises not uniform. Sounds pretty bad. Very noticeable. Only when restarted after fully warmed up. And only after sitting 5-10 minutes. Wont do it if turned off and started right back up immediately. This will keep going on until back on the road then it goes away until turning the engine off again. Its done it ever since it was brand new first day home from the dealer. It sounds like metal on metal, like something is vibrating and contacting something else. But i cant find anything hitting. Sound is right at the engine ip around the heads. It has gotten worse since having the stage 2 torque cam done. Any ideas appreciated.
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Seasoned HDF Member
Joined: Sep 2009
Posts: 17,148
Likes: 6,171
From: SE Michigan
2019 Road glide 114. Bike will make a series of clacking noises not uniform. Sounds pretty bad. Very noticeable. Only when restarted after fully warmed up. And only after sitting 5-10 minutes. Wont do it if turned off and started right back up immediately. This will keep going on until back on the road then it goes away until turning the engine off again. Its done it ever since it was brand new first day home from the dealer. It sounds like metal on metal, like something is vibrating and contacting something else. But i cant find anything hitting. Sound is right at the engine ip around the heads. It has gotten worse since having the stage 2 torque cam done. Any ideas appreciated.
Road Warrior
Joined: Apr 2017
Posts: 1,451
Likes: 230
From: United States
2019 Road glide 114. Bike will make a series of clacking noises not uniform. Sounds pretty bad. Very noticeable. Only when restarted after fully warmed up. And only after sitting 5-10 minutes. Wont do it if turned off and started right back up immediately. This will keep going on until back on the road then it goes away until turning the engine off again. Its done it ever since it was brand new first day home from the dealer. It sounds like metal on metal, like something is vibrating and contacting something else. But i cant find anything hitting. Sound is right at the engine ip around the heads. It has gotten worse since having the stage 2 torque cam done. Any ideas appreciated.
I would have taken it back to the dealership before I got it home.
Wiz 🤔