Any 2018 Softail owners having sumping issues?
Grand HDF Member
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From: 3rd stone from the sun
So is the M8's problems strictly being reported by the those in the touring family? I was wondering the same.I dont think I read or heard from any '18 ST owners. Was hoping mid '19 I would be looking at the M8 and hopefully the teething pains have been dealt with & fixed.. I'll keep the '02 and bring in a new steed 2 is always better than 1 ! ............
Stellar HDF Member
Joined: May 2010
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Stellar HDF Member
Joined: May 2010
Posts: 3,453
Likes: 249
There's one or two long threads on the M8 bike forum about this issue and sumping is down on the Harley bulletins for all M8 engined bikes, though it mainly seems to be affecting the 2017 baggers. There's been a few oil pump upgrades which seems to be the problem and from what I can gather it's guys doing high speeds at high revs that mainly seem to be affected.
like all things it's best to wait till Harley's iron out all the bugs before buying, might have to wait a long while though, took them about 7 years to correct the cam tensioner shoes on the 88 TCs, and they only did that when they brought out the 96 TC.
like all things it's best to wait till Harley's iron out all the bugs before buying, might have to wait a long while though, took them about 7 years to correct the cam tensioner shoes on the 88 TCs, and they only did that when they brought out the 96 TC.
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From: Texas
Just speculated on this exact question over in the M8 forum. I do think that sumping is vastly more reported on the Touring bikes than it is on the Softails.
I'm thinking that the original Harley bulletin said that sumping happened under high revs and heavy load. A Softail weighs around 675 pounds, give or take 25 lbs depending on model. (except for the Heritage, that's the heaviest at 728). A touring bike weighs at least 100 pounds more than the heaviest Softail, and as much as 300 pounds heavier than the lightest Softail (CVO Ultra at 944 pounds, vs. the Slim at 642). Pushing around an extra 300 pounds has got to qualify as being under heavy load, versus a bike with the same engine pushing around 300 fewer pounds.
So I would guess that there are a few reasons we're going to hear about sumping much more frequently with the Touring bikes than the Softails:
1) the Touring bikes have a heavier load to push around, and according to Harley's bulletin, heavy load is a factor.
2) there are probably way more Touring bikes on the road, given that they've been out an additional model year.
3) I think (but have no data to support) that the Touring bikes are exponentially more likely to be ridden two-up than the Softails are, especially for long distance, which will drive up the load on a 107 Touring bike substantially.
Does this mean sumping won't happen on a 107 Softail? No, of course not, it certainly might. If I'm not mistaken, we do have a report of someone who sumped a 107 Fat Bob. But it just seems that perhaps it's less likely to happen on a Softail for a number of factors as described above.
So I would guess that there are a few reasons we're going to hear about sumping much more frequently with the Touring bikes than the Softails:
1) the Touring bikes have a heavier load to push around, and according to Harley's bulletin, heavy load is a factor.
2) there are probably way more Touring bikes on the road, given that they've been out an additional model year.
3) I think (but have no data to support) that the Touring bikes are exponentially more likely to be ridden two-up than the Softails are, especially for long distance, which will drive up the load on a 107 Touring bike substantially.
Does this mean sumping won't happen on a 107 Softail? No, of course not, it certainly might. If I'm not mistaken, we do have a report of someone who sumped a 107 Fat Bob. But it just seems that perhaps it's less likely to happen on a Softail for a number of factors as described above.
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Road Warrior
Joined: Jul 2014
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From: VA
No issues either. And I have tried to make it sump by running on the interstate in 5th gear. Not sure how much different the cases are on the Softails. But the latest speculation is that the problem is more due to case design than the oil pump.
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Case design is deffinately a factor in the touring motors. I’d like to know what’s different (if anything) in the Softail case design. Maybe the 100+ lbs lighter makes a difference too.