Viscosity siphoning test: 10–40 oil vs. gasoline

Drain­ing into pan #2, who woul­da thunk it??

On my Ore­gon bike jour­ney I checked the oil lev­el on the bike for the first time in Bend. Alas, the cir­cu­lar 3/4″ win­dow in the crankcase to mon­i­tor the “H“igh and “L“ow lev­els was com­plete­ly emp­ty. So I found and rode to a cycle shop and added a quart of oil. Right up to the “H“igh mark, great. I lat­er added 12 more ounces in Ashland.

Upon arriv­ing home I put the bike on its cen­ter stand for the first time since leav­ing. YIKES! The mon­i­tor­ing win­dow was com­plete­ly full, way above the “H“igh mark. How far above? I could not tell. I emailed this obser­va­tion to friend Jeff and he respond­ed thus: “When you are check­ing the oil lev­el, are you sure the bike is lev­el? I don’t think you can check it on the side-stand. It needs to be checked on the cen­ter stand. Anoth­er thing: I’ve heard, for small engines, too much oil is way more dan­ger­ous than not enough oil. You might want to con­sid­er drain­ing it to the right level.”

Yes­ter­day I decid­ed to fol­low Jef­f’s advice and remove the extra oil. It turns out that the nice skid plate I added under the engine goes not allow for a grace­ful reduc­tion of oil quan­ti­ty. So I elect­ed to try and siphon out the extra oil and went off to an auto parts store and pur­chased three feet of 1/4″ fuel hose. Return­ing home I got a nice quart pan (the yel­low one above) and went at it. Start­ing a siphon with 10–40 oil is some­what dif­fer­ent than with gaso­line or water 🙂

It took me about five tries to get it flow­ing to the yel­low pan along with the usu­al treat of some flu­id in my mouth. 10–40 oil also flows MUCH slow­er than gas or water, at first I did not think it was flow­ing at all. But 25 or 30 min­utes lat­er the yel­low pan was full, yet there was no change in the mon­i­tor­ing win­dow so I employed pan #2. After anoth­er 15 min­utes the lev­el in the win­dow was between the “H“igh and “L“ow lev­els so I stopped the siphon and poured oil care­ful­ly back into the bike until the lev­el was right at the “H“igh mark.

After fin­ish­ing up I took the bike off the cen­ter stand and put it on the side stand. The mon­i­tor­ing oil win­dow was com­plete­ly emp­ty, just like in Bend. And how much oil did I end up remov­ing from the bike? As near as I could tell the total of the amounts I put in in Bend and Ash­land. Kudos and thanks to friend Jeff.