Sorry for another sumping question/thread. I am looking for a used 2017/2018 Limited or Road Glide Ultra, hopefully stock. Is there an amount of mileage after which it is safe to assume there will not be a sumping problem? How can I tell if a used bike has had a sumping problem.?

 

 

That depends on who you talk to. If someone has experienced sumping, they are going to give a different answer than those who have not.

Roll the dice and take your chances.

Edited to add that the larger the displacement, the more likely it seems to sump. Quite a bit more prevalent on the 117 CVO engines. My 120 sumped one time.

 

The sumping issue seems to be most apparent when a Stage III or Stage IV has been done. Stage I and Stage II don't seem to have many problems.

 

 

Yep, you can assume it won't sump the day you buy it.
Does sumping occur on some bikes? Yes.
Is the number of bikes that sump a tiny fraction of all the new bikes? Yes.

 

Nothing mechanical comes without risk of some sort of failure. Of the bikes that I've heard of sumping, they had had as little as 17 miles on them (I think) to upwards of 21k miles. So you just have to look at a bike you like, get it's service history, and take a leap. If sumping specifically is you concern, try and find a higher mile (30k+) one owner bike that was ridden very hard by it's current owner. but has good maintenance records.

 

 

Ride the bike hard and you probably will join the sump club, otherwise you will probably never encounter a problem. JMHO

 

​​​​​​Nonsense, there's no way to make any M8 "probably" sump. IF (and it is extremely unlikely) but IF your bike is even capable of sumping, then yes, riding hard is how you bring it about. But you can ride the vast majority of M8 bikes as hard as you want and they still won't sump.

Unless you're talking about a Stage IV CVO. I think those are disproportionately likely to sump. I don't know if the likelihood rises to "probably", but I think the risk of sumping increases substantially if riding a Stage IV CVO hard.