Oh no, no worries there. I get the mechanics behind it and what's occurring. Also not concerned about damage. But clearly the design is to retain the oil in the tank. Seems to me there must be a component (I'm thinking check valve) allowing this to occur. Potential problem I see with this is overfilling with oil depending on how fast your leak is and when you check your oil.

 

Common does not mean they all do it...

 

I think it depends on how the oil pump vanes are lined up when it's shut down as to how quick or how slow the oil will weep past the pump and into the case.

 

Also there are no one way check valves to keep this from happening. One less thing to break. Basically, it is an open system.

 

I'm no expert, but I had it happen to my Heritage and I did some research on it. Here's some of what I read that causes sumping;

1. Out of tolerance scavenge side of oil pump (wear or minor scoring damage from debris).... This seems to be the most common cause I found, discussed about engines that ran well and started sumping as miles/age ad up.

2. Seal of oil pump miss aligned with the scavenge port hole of the engine case. This is caused during installation of cam plate during cam chest work.

I've read that twin cams are not designed to sump, with components in good condition they shouldn't sump, but if it does, it's usually not a major issue.... Don't check the oil cold (unless you want to overfill and have the dipstick pop out) and drive slowly at first start to allow oil to be pumped back into the oil tank...


However... if it starts sumping so badly, that more than about 10oz of oil stay in the cam chest, the bike will lose power and run poorly. This condition is usually cause by pinched/damaged/missing cam plate o-rings during installation or damage to the oil pump gerotors....

FWIW.......

 

Yes...sumping...IMO, not good. The tank typically "should not" drain. That should not be common for a dry sump oil system. Too much oil in the case and the crank will splash in the oil. This is what causes the power loss. Worse yet, a crank splashing in oil will cause the oil to foam and an oil pump will not pump air. Insert your own conclusions as to what results if that starts to happen. I know the day my tank starts to completely drain into the crank over any amount of time, I'll be investigating why. To each his own, but I'm with hattitude that this is not normal.

 

I'm with you and hattitude also. 2014 Slim w/ over 12k mi. so far and although bike never sits for more than two weeks with that occasional but rare three week period because I'm a ahemm; 1%'r all year long rider (that's what 1% really means b: ), well, my tank level stays where where it should.
Should probably add that after the initial 500mi. break in I quickly switched to Mobil sinth 20/50 to which after 1,000 miles has been AMSoil product in all three holes.
I ride it like I stole it too. Can't help it LOL

 

Hey...I'm with you! The ONLY reason my bike gets stored is due to salt/chemicals on the road. I do NOT stop riding due to temp or weather. I don't put mine away until after the first salting and I take it out after I stop seeing signs of the salt dust on the vehicles. 2015 I got in April and put 5,000 on it by October, and I travel A LOT for work (meaning I'm gone a lot and still put that many miles on it) My bike has Amsoil in everything that will hold a fluid!! Although, I'm sure Amsoil is not the reason our bikes don't sump, lol...or maybe it is!!!

 

it is

 

Well its been interesting to say the least, And thanks for all the responses. I was not to worried about it losing the oil into the crank. I was just very curious as to why the oil light took so much longer than normal to go out????? If the moment I start the motor the oil pump pull from the crank as well as from the oil tank shouldn't the light go out in the usual 2 seconds.