new to the Evo world, just picked up a 92 FLHTC and wonder what oil is recommended and also checking tranny and primary is oil in the primary shared as in my old shovel or is it seperate?

 

There's a million oil threads and a million opinions on what oils to use. No, the primary oil is separate on your bike, not circulated through your motor like on a shovel.

My oil choices:
Engine: Genuine H.D. non-synthetic.
Primary: Synthetic automatic transmission fluid (ATF).
Transmission: Mobil SHC630.

 

Oh, and you need the official factory shop manual.

 

 

Where's Spanners when you need him?????????

 

any 20w50 oil, some use 20w50 in the trans, some use gear oil, primary is where you get the biggest variation, just use something friendly to wet clutches. I think next change I'm going to try either Bel Ray or Drag Drag Specialties primary fluid.

 

yeah I have several shovel manuals, have to pick up one for the evo asap

 

Get the the one from HD. Much more detailed that the clymer or others out there. I have a clymer for my bike and bought a HD after reading suggestions on here and there is a world of difference in the two manuals. Definitely worth the extra money.

 

As for the oil as said many of opinions but we live in about the same general area as far as climate goes and here is my $.02. Engine I use Castrol GTX 20w 50 conventional in fall, winter and spring. Soon as it gets hot I switch to Spectro 25W 60 conventional as well. Trany I use Mobile One 75w 145 Full Synthetic gear oil. I have been experimenting with primary lately and really like the results I have gotten from the Mobil one 4t 10w40 fully synthetic racing oil. I installed new clutches and plates at the same time I switched so really don't know if it is that much better than the HD Formula+ or not. Most on here will recommend conventional motor oil for the evo as it seems to quiet them down some and Synthetics seem to cause oil leaks i our old motors. The theory being that the synthetics clean so well that it removes the crude built up around our old gaskets that have been helping seal our engines.

 

Oil....

Been using the Harley 20w50 motor oil since I got the bike new in 93. Used their primary oil too, until they dropped it and came out with Formula+, which I now use. I change engine/primary oil every 2500 miles. Transmission gets either Mobil1 synthetic gear lube, or Valvoline semi-synthetic gear lube. Whichever I can find when I'm doing the trans, which is every other oil change.

Make certain you get the correct filter. An EVO filter is different than a TwinCam filter.