Got a fatboy few days ago, don't have a clue how to check primary fluid, what is the fluid capacity?
Can I use Amsoil 20w50 V-twin on all three? Tranny and primary I mean, I can't seem to find the fluid type in the manual. Thanks Alex

 

Set the bike upright, on the stand won't do it...remove the cover, and the fluid should come just to the bottom of the clutch basket...when I do the fluids, mine takes just about 1 qt...some bikes may be a few oz more or less...
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No reason you can't use the Amsoil 20 - 50 in the primary, although it's expensive...but for thr tranny, I'd use a heavier gear oil...I use Mobile 1 in the engine and primary, and their 75-90 gear oil in the tranny...

 

just to the bottom of the clutch basket
Do you mean I have to open the derby cover?

 

If you wnat to see it, yes you should remove the derby cover.&nbsp\\; T-27 is the size of the torx.&nbsp\\; A 25 will strip it.&nbsp\\; Get a wratchetable t-27 makes it much easier. &nbsp\\;

 

You know what, I hate to open the derby cover, heard bad story about broken torx bolts, can I just drain it completely and top it up to spec?

 

That's how I do it.&nbsp\\;

 

I assume the inspection cover is where I fill, correct?

 

I cannot find 75-90 mobil 1 here, any other option? Does tranny take special 75w90? I can get redline 75w90 here. Thanks

 

You can use what ever you want.
However most do not recommend the use of any sny lube or oil in Primary HD F+ is most common.
Now engine and tranmission is a differnt story.
The use of any of the major bands of true 100% sny in there is best.
Think about the tranmission while you can use the 20/50 sny&nbsp\\;\\\\\\;\\\\\\\\\\\\\\;oil in there, why when there are great tranmission lubes made for it. examples are Spectro Platium for 6 speeds, Redline shook proof heavy, M1 gear lube or even amsoils tranmission lube.
The couple bucks extra it will cost is well worth it.
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&nbsp\\;\\\\\\;\\\\\\\\\\\\\\; To check primary bike needs to be stright up this is very important.( bike warmed up)&nbsp\\;\\\\\\;\\\\\\\\\\\\\\;Lube should be at bottom of clutch diaphragm spring. Do not over fill.
It is alway best to check you manual for your bike on amount and proper fill.
Nice looking FB While I really like my RoadGlide my FB still is the one Love to ride.
If your new to HD try not to get caught up in all the BS about having to do this and that to your bike to save it. The bike will serve you well and your off to a great start good oil and lube is the best thing you can do for you bike and will return you many miles of trouable free service.

 

I fill through the inspection cover with a funnell.