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What fluid to use


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Hi,I'm new to riding Harleys.But been riding 30yrs.I just want to know what type of oil and transmission fluid to use in a 1984 fltc evo.?The closest shop I called and they told me that it was just harley brand and I had to buy it from them.I hope I put this in right spot on page -new to computer also.Thanks in advance

I moved your post to the general tech section for better exposure. The self help area where you originally posted this post is mostly for questions pertaining to a post already in that section.

In regards to the oil question, your bike being an evo can use either 20/50 , 20/60 or straight 50wt or even 60 wt depending on your area temps where you ride.
The heavier weight (50-60) would be best for summer time temps and would be difficult cranking in colder climates.

As far as transmission oil, use a quality GEAR oil and not engine oil. Some suggestions would be Mobil 1, Redline, royal purple which should be available at a parts store like NAPA, autozone or similar stores. Gear oil will give you the best service as it is formulated to withstand the extreme environment of the transmission gears.

Hope this answers your questions.
Thanks for the help.Auto zone was way off.They wanted me to put 10w30 in transmission.I found a castrol20w50 motorcycle oil.The fluid in my tranny is milky white.I was told it's because it has water in it. Thank again Glider for help.I live in tenn. it hasn't rained for 2wks.And over 95 every day. Tim
The milky white in the trans oil is definitely water mixed in and can even come from dampness if the bike isn't heated up enough when riding like on short trips.

The castrol is a good choice also for the engine but use a gear oil 75/90 or 75/140 in the trans. It will shift better, you'll find neutral much easier and it will live longer.

I'll also add at this point being you asked that motorcycle specific oils are formulated for the temp difference associated with air cooled engines over water cooled engines and contain such things as moly which is a wear reducing additive . I feel that the extra cost of the MC specific oils is worth the extra cost but not everyone feels the same and automobile oils get chosen for the lower price.

With your choice of oils for your particular bike being an 84, I would stay away from synthetic oils unless you know that they have been used previously. Synthetics can bring about some seepage in the various seals in an older bike because of the higher cleaning characteristics of the synthetic itself over dino oil and the advancement of the seals themselves used in the newer bikes.
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