First time motorcycle owner, took up possession of my dads 1982 XLH that has been sitting in a garage for roughly 10 years now. I am new to motorcycles and have a good concept of engines and how they work, as well as I like to work with my hands, which makes this bike perfect since I will have a lot to do...

Current progress done on bike:
Plugs changed
oil and filter changed
Gas tank soaked in vinegar and cleaned out
fuel line and filter changed
rear brake replaced(piston was frozen)
brakes bled
Carb rebuilt and cleaned
New battery

Need to do:
OG seat cleaning/restoration
New tires
primary oil change
Good cleaning
replace handlebar bushings

Now the bike runs pretty well(as far as I know). When i am throttling up, past 1/2 throttle the bike loses power and will not rev any higher. My guesses would be something with fuel delivery is off, tank not cleaned enough, there is a little bit of sediment in my fuel filter after a little bit, which could also be causing my carb to get clogged up again. Seems like I could ride 1/2 throttle all day no problem. I have been considering taking it to a shop but wanted to check to see if anybody had any ideas or had seen the issue before my wallet runs dry. Any advice on the bike in general, or additions to To Do list would be much appreciated!
Video of Noise after 1/2 throttle:

 

Might want to revisit the carb. Check for a clogged main jet.

 

I was thinking carb also. I did see the list had said it was rebuilt.

 

Could be the float level is set too low. There is a good picture in the Factory Service Manual 99484-85 thar shows how to set it.

EDIT: I had a similar symptom. It would accelerate fine up to about 60 MPH, then it would sputter and die. I would wait a few minutes and it would run fine again for a while then sputter out. I found that the fuel level was set too low. It would simply run out, then fill up again.

 

When you cleaned the gas tank, did you also remove the petcock and clean it real good? They get gunky. Make sure fuel is flowing through it at a pretty good rate. Also make sure your gas cap can breath. It's probably what Mick said but it won't hurt to check these things too.

carl

 

Having thought about this some more, it did not die as in shut down - rather it sputtered along not accelerating. So I would just coast/idle along for a minute and then it would be ok again.

 

I'm not seeing a carb support bracket on your ride. I think you'll find the general consensus is every Ironhead needs a carb support bracket. aka I'd suggest you fix that.

But back to your problem.....

Tell us about your ignition system. Electronic or converted to points ?

Your description of the symptom(s) makes me think gas or ignition or BOTH. Either can produce what you're describing. Once your gas woes are cleaned up, check your timing with a timing light. And if you've got points with mechanical advance..... there's more involved to get the timing right, so talk to us.

 

Wow, good eye. All bets are off without that bracket. The carb/intake won't have a chance.

carl