Looks like I unfortunately joined the HD M8 Sumping club. New 18 FLHXS w/Harley stage 4 kit and recommended oil pump per service Bulletin 1450, 1600 miles. Bought the week after the 18s came out. While riding Saturday I experience loss of power and bike running very rough. Pulled over, checked oil, 1 3/4 quarts low. I check my oil regularly, the day before it showed full. Walked to an auto parts store and picked up a few quarts. Added the oil until dipstick showed full. Fired up, bike ran great, low oil made no sense until I read this thread about sumping. Got home and the oil stick showed way way overfilled. Drained the excess out, dealer is picking up the bike in the next few days. This really sucks.

 

Sorry to hear of the problems on your new ride. Certainly no one should have to deal with this. Can you give us some more details. What temp was it outside? What were you doing? Certainly not saying you were doing anything wrong. I think the additional info will just be good for others to hear.

 

Sorry to hear this, I feel your pain though having had a 2017 stage III that failed myself.. So now what? a new kit? will you trust it? Really sucks. I had to walk away from my 2017 for a stock 2018. almost 6000 miles now, but every time I see a pic of my old bike I get really pissed.

 

Outside temps were upper 50s and sunny. Had just pulled off the highway and was at a stoplight on the exit ramp. Bike sounded rough, like it was out of tune. Then I noticed loss of power in 2nd, 3rd and 4th gears. Something wasn’t right but no dummy lights came on, the dash display read oil pressure “OK”. Pulled over, the Harley LCD temp dipstick flashed LOW OIL and temp was either high 100’s or low 200’s, nothing that concerned me. Pressed the dash display again and now it read “check oil”, but dash oil light never came on.

 

When did you have the Stage 4 upgrade installed? At delivery back in August or later? You might find this thread describing my sumping experience of value.... https://www.hdforums.com/forum/milwa...ddressing.html

 

Waiting for dealer to pick it up to formally diagnose the problem. I’m afraid from all I’ve been reading that this may be the beginning of an ongoing problem. I’m sick about it. I have a ton of money in mods for fit in addition to the Stage 4 kit. FBI Drop Seat kit, custom seat, TP, LED lighting, Daymaker headlamp, Baker F6R Reverse gear, custom fabricated kickstand assist and on and on. The reverse is very helpful as I’m a left leg amputee. I ride 14,000 miles a year all year round.

 

Bought bike 8/25/17. Stage 4 kit was installed and completed around 3 weeks later. Thanks for the heads up, it looks to be very informative. What I take from everything I’ve read thus far is that Harley still doesn’t have a definitive solution. If I have more engine issues after this go round I’m done with Harley. I waited a long time for my 18, and even longer for the fit mods. I couldn’t be more disappointed.

 

Hard to say. You had the oil pump installed before the latest oil pump design changes they made in mid October 2017. According to my local HD Dealer Rep that I've been dealing with, there have been "no reported sumping issues on any M8 bike since the last oil pump design was installed using the latest oil pump bolt torquing process".

I sure hope that's accurate because I am about to upgrade my 3rd 117 M8 engine to Stage 4 for the 3rd time. The entire install is being done at my local dealer but with onsite supervision by the dealer rep and HD technical support. There can be NO EXCUSES this time if there is a sumping engine failure. I will be starting a new thread to share the process, findings and results.

 

While nothing is "for sure" there is at least hope for your build, HD came out with a new oil pump that is said to address this issue. Your build was prior to this new pump availability. I have attached the latest Bulletin so you have the correct information at hand.

 

I;m just leaving it stock and keeping a warranty. I'm sorry about your problem.