Sumping? Questiom
Member
Joined: Jul 2009
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The facts would suggest the “obsolete” M8 oil pumps did NOT “do the job as intended”. Otherwise HD would have never had to issue 10 revised versions of SB1450 or the dozen or so redesigned M8 oil pumps they have released every couple of months to address sumping.
Last edited by Heatwave; Oct 3, 2019 at 05:54 PM.
Road Warrior
Joined: Apr 2017
Posts: 1,451
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From: United States
Now Im not saying the problems still there, But I wouldnt buy one with your money.
Wiz 🤣
Road Warrior
Joined: Apr 2017
Posts: 1,451
Likes: 230
From: United States
HD is never going to admit to anything. The only evidence from them comes in the forum of multiple pump redesigns, which we all know wouldn't be happening if there wasn't a problem.
Anymore, sumping has gotten to be like a conspiracy theory.
Either it happens to you and you know it, or it doesn't happen at all.
Anymore, sumping has gotten to be like a conspiracy theory.
Either it happens to you and you know it, or it doesn't happen at all.
3 years down the road the best fix thats been offered is an oil pump, a rubber hose vent pipe, And Ill swap out ya 1500 mile engine cos we dont know what the hells going on but well keep ya money, tie up ya bike in service till we get approved from the mothership for repairs.
The M8 just aint worth the price of 30,000 of Advil.
Wiz 😟
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From: Inland NW
Road Warrior
Joined: Aug 2014
Posts: 1,703
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From: SE Michigan
In reading the SB, it states a cause is extended high rpm or heavy loaded.
Exactly what rpm and how long.
My furthest trip is 250 miles one way, one stop...80 to 85mph and I'm 280ish geared down.
This type of riding was enough to make it transfer, which was fixed at 1500 miles with the vent tube.
Over 7K now, not an issue.
What is the magical load and rpm HD is stating could cause sumping?
My bike lives at 2500 to 3500 rpm unless I'm idling through my streets or passing/getting up to cruising speed.
Keith, what rpms or loads caused yours to sump?
Exactly what rpm and how long.
My furthest trip is 250 miles one way, one stop...80 to 85mph and I'm 280ish geared down.
This type of riding was enough to make it transfer, which was fixed at 1500 miles with the vent tube.
Over 7K now, not an issue.
What is the magical load and rpm HD is stating could cause sumping?
My bike lives at 2500 to 3500 rpm unless I'm idling through my streets or passing/getting up to cruising speed.
Keith, what rpms or loads caused yours to sump?
Seasoned HDF Member
Joined: Sep 2009
Posts: 17,148
Likes: 6,171
From: SE Michigan
In reading the SB, it states a cause is extended high rpm or heavy loaded.
Exactly what rpm and how long.
My furthest trip is 250 miles one way, one stop...80 to 85mph and I'm 280ish geared down.
This type of riding was enough to make it transfer, which was fixed at 1500 miles with the vent tube.
Over 7K now, not an issue.
What is the magical load and rpm HD is stating could cause sumping?
My bike lives at 2500 to 3500 rpm unless I'm idling through my streets or passing/getting up to cruising speed.
Keith, what rpms or loads caused yours to sump?
Exactly what rpm and how long.
My furthest trip is 250 miles one way, one stop...80 to 85mph and I'm 280ish geared down.
This type of riding was enough to make it transfer, which was fixed at 1500 miles with the vent tube.
Over 7K now, not an issue.
What is the magical load and rpm HD is stating could cause sumping?
My bike lives at 2500 to 3500 rpm unless I'm idling through my streets or passing/getting up to cruising speed.
Keith, what rpms or loads caused yours to sump?
But at no time (all 3 times) was I at what I would consider high RPMs for an extended period. 90 mph is only about 3300 RPMs if I recall correctly.
I never got more than 600 miles on the replacement engines. Last time it happened, they replaced the bike, from a 17 to an 18, but I just traded the 18 in for a 2020 Road Glide Limited and I freakin love it. 582 trouble free miles so far!
(I rode the 18 to and from Sturgis as well, no issues. Had about 9400 miles on it when I traded it in for the 2020)
Last edited by Keithhu; Oct 4, 2019 at 06:43 AM.
HDF Community Team
Joined: Mar 2017
Posts: 7,882
Likes: 4,442
From: Texas
In reading the SB, it states a cause is extended high rpm or heavy loaded.
Exactly what rpm and how long.
My furthest trip is 250 miles one way, one stop...80 to 85mph and I'm 280ish geared down.
This type of riding was enough to make it transfer, which was fixed at 1500 miles with the vent tube.
Over 7K now, not an issue.
What is the magical load and rpm HD is stating could cause sumping?
My bike lives at 2500 to 3500 rpm unless I'm idling through my streets or passing/getting up to cruising speed.
Keith, what rpms or loads caused yours to sump?
Exactly what rpm and how long.
My furthest trip is 250 miles one way, one stop...80 to 85mph and I'm 280ish geared down.
This type of riding was enough to make it transfer, which was fixed at 1500 miles with the vent tube.
Over 7K now, not an issue.
What is the magical load and rpm HD is stating could cause sumping?
My bike lives at 2500 to 3500 rpm unless I'm idling through my streets or passing/getting up to cruising speed.
Keith, what rpms or loads caused yours to sump?
My bike also lives at 2500-3500 rpm and it has not exhibited any symptoms of sumping, but remember theres two types of M8s - those that have sumped, and those that dont know if theyve sumped.
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Road Warrior
Joined: Aug 2014
Posts: 1,703
Likes: 909
From: SE Michigan
I just want to clarify: you were reading the sumping service bulletin and it states that high load and/or high rpm can cause sumping, but you don’t see sumping at high loads and/or high rpm? The only thing you have seen at high load and/or high rpm is the unrelated issue of primary-transmission transfer? Consider yourself lucky! Lol
My bike also lives at 2500-3500 rpm and it has not exhibited any symptoms of sumping, but remember there’s two types of M8s - those that have sumped, and those that don’t know if they’ve sumped.
My bike also lives at 2500-3500 rpm and it has not exhibited any symptoms of sumping, but remember there’s two types of M8s - those that have sumped, and those that don’t know if they’ve sumped.
Regarding transfer, if I putt around town, 55 and below, no extended time on the throttle...it wouldn't move a drop.
When I took it to work, 1 way is 26 miles and 90% freeway at 80+, it transferred.
I would think these are the same conditions that would apply to sumping.
But you are spot on B, I have not yet experienced it.
No loss of power, no burn smell, no engine braking feel...
Keith, got it...let's hope the bad luck is behind you.
Last edited by dajogejr; Oct 4, 2019 at 08:58 AM.
Road Warrior
Joined: Apr 2017
Posts: 1,451
Likes: 230
From: United States
Buy one if your confident enough you wont have a problem with a 25+ bike sumping,
Dont if ya so ..... Thats all.
Wiz 🍻
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