88ci '06 dyna. Using Syn 3 but was recently told Klotz was the best. It also appears to cost the most. I bought it with 10,300 last yr and now have 21,300 on it. I would like to ride it a few more yrs if possible so if I need to step this up I will.

 

Switched from Syn3 to Mobile 1 15w50....Very pleased with the M1...much quieter and more power.

I will never go back to Syn3.

Lots of oil opinions, but I prefer to change often as oil filters simply can't clean the oil 100% and contaminants in the oil are what cause wear...so even though the oil may be "good" for 5000+ miles, it will have more and more contaminants.

Think about it...you buy the worlds absolute best oil at $100 a quart...then add a tablespoon of sand to the oil every 500 miles... The oil itself is still "good", but it's full of sand...how is that oil going to counteract that?....it's not...change often is what I'm sticking with...

$4.80 a quart for the 15w50 at Walmart (in the 5quart jug) so I run that 2000 miles, drain it, filter it, and then reuse it in my lawnmower. You can buy 1/2 micron water filters cheap (motor oil filters are 20 micron or greater), build a homemade setup, pour the oil in, a week or so later it's all run through the filter and ready for your lawn mower or some other old engine...maybe you've got an oil eater beater...