what about using synthetic oil in 68 flh?

 

It's probably ok (a couple of my friends do use multigrades and synthetic with no problems) but I still use 50 mineral oil in my 81 and 83. Only real problem I see is that synthetics really seem to thin out when hot so you will at least likely find the bike sounds noisier than what you're used to.

 

while i agree it might be ok

we see oil leaks develop after using it that were never seen before

i have and do use 20 - 50 if its a good sealed motor that has real valve seals not the tin ones / with of course moly rings

 

Agree... But, I use 50wt... synthetic Blend... but... 50 wt!!!
This ain't no EVO!!!!

 

Shovels will run 20-50 but the stock hyd. lifters will get noisey. Synthetics want OUT, every gasket and seam on the old ones will start weeping or showing wet, just the nature of the product. The older pre 80's castings were rough and porous to a fault, I've seen rebuilds that didn't reseal the insides of the cases weep oil through the sides of the cases, syn would be inviting the bike leak. Plus every shovel I've seen running syn has sounded like a tool bucket rolling down a hill they clatter so much.

Stick with good old 50 or 60 straight just for the peace of mind.

 

OK no synthetics. I got my 1968 flh in 1978 and always ran hd 105 grade - when I found milwaukee twins was selling sae 70w I started using that. Now I guess they stopped selling it. I found another 70w but it's not sae rated - so what do the experts think?

 

If it's not rated I wouldn't use it!! Rating means the oil has passed a certain minimum test standard. Look for another oil.

 

ultima oil from mid west is very good 50 60 and 70 weights available

lucas also has the 3 weights

some guys also use aircraft air cooled oil - yea its fine

must be another 5 or more company's still selling single weight Harley oil as well as the dealer net work

in my shop i have both lucas and ultima in 50 and 70 weights and we blend the two for mid season temps

 

Glad you brought that up John... the Custom Blended oil thing that is... I been doing it since even before we had our [now gone] shop..
Began with my Pickup truck.. 4 quarts of whatever was in the Oil Bay... and the last quart of Mobile one 10/30.. Then the wifes car... Both showed consumption improvement, cleaner [based on rocker covers], and seemed to run cooler, yet warm up faster...
Began putting [motorcycle rated] mobile one like 1/2 quart to the other 2-1/2qt of 70wt in my old SuperGlide... Would Not stop the Practice, till a Complete rebuild.. After rebuild... Blended 20/50 was called Castrol S semi-synthetic... haven't been able to get it for quite some time [hell it came in cardboard cans with tin tops]... and am Still seeking a reasonable replacement... leaning toward Spectro!! But considering going back to a Custom Blended concoction!!!

 

I wanted to get lucas 70 but it's not rated - makes me nervous