I got my bike working maybe a month ago, been riding it a couple days a week after work. I have been keeping to county roads and neighborhoods because I still just have my permit (don't tell the police), but I went for a maybe 20 mile ride yesterday down a two lane highway with a 55 speed limit. Bike did fine for maybe 16 miles, then all of a sudden when I would give it gas it would start to die. I was crusing at maybe 5k rpm and the bike had nothing to give. I slowed down to maybe 35 for about a minute and then sped back up and everything was fine. Maybe 10 miles later same thing happened. Cruising at 55 and give it gas and it just slows down, sputters, wants to die. Slowed down to 40 for a minute and everything was fine the rest of the way. What could be causing this? Should add my bike has Yosh slipon, lunchbox, and 147.5 mains. Have yet to adjust the valves since I got it and I have 12k miles. Also took a while to get the carbs working good, and I question whether they are adjusted perfect or not. So far this is the only trouble I've had with the bike since I started riding it.
Just realised I could have explained all that with way less words. I apologize for the horribly long post.
I am guessing fuel starvation. Culprits include rust in tank, and other forms of crap clogging up gas supply.
Do you have an inline fuel filter to the carbs? If so, what's the condition?
set the frame mounted petcock to the PRI position. If your motorcycle runs normally, check your vacuum hoses and make sure there are no leaks. If there are no leaks, your petcock may have crapped out on you and need modification/replacement.
It could be other things, but that is how mine is currently running.
Tank is fairly new and rust-free, its an 06 tank on my 92 bike. I don't have an inline filter, but will check the carbs for crap tomorrow. Thanks for the quick responses.
bet its bad vacuum in the petcock, go to PRI and try.