[skelbert]

Hey.
I recently bought a vf500f (I now have 2 other parts vf500's as well) and it's running poorly (actually, it's almost displaying the same exact symptoms as yours was/is.
I was just looking for some pointers.
First, My bike runs (it did, but i've now started having trouble getting started, but more on that later). I've been able to take it up and down my flat street more than 20 times in a row (I don't normally ride yet) w/o any problems, and I assume I could do much more w/o any problems occuring. I decided to take it to some other streets, ones that have hills on them. When I did this, it was fine the first few times, but than began to slowly cut out. Power dropped, and the bike cut out and died. I couldn't get it to start properly for 4 minutes, after which everything was normal, I did a few more runs, and the same problem happened.

The next day, I do the same, but go to a different hill which isn't as steep, just long, and the same problem occurs a few times. The third time, I took it out about a mile from my house, and it had died twice by the time I arrived. I got it started again, and it idled just fine for 10 minutes. I rod it up and down his street (flat), and it died in the same manner as before on the flat surface. I started to ride it home, took a different route, went up a slight hill, and the temp bar was almost at the "H", and it cut out and died as it had before. I stopped, put it on the stand, and found out that the coolant had overflowed.

Now I can't get it to start or idle properly as before. I can get it to turn on, and barely hold at 1000 rpm's with the choke fully engaged, and if I take the choke off, or try and give it gas, it immediatly dies.

Could you help me diagnose/solve this problem? I'm not sure, but I guess that either my water pump is fouled, my radiator is clogged (in regards to the overheating) and for the power and cutting out, my carbs need to be cleaned, and my gas is stale and sediment is collecting? Any thoughts. Thanks

[unwise]

It is likely that the overheating problem is not related to your cutting out problems, unless the carbs are getting so hot that the fuel is vaporizing.

Does your bike have a thermostat? It may be bad.

The fuel problem sound a lot like gunk in the bowls, that are getting into the jets. Have they been cleaned recently? (Well?)

[skelbert]

It has a thermostat, and i'm going to replace some parts in it (hopefully that'll help).

I actually believe (just got contacted by a motorsports owner) that my vacuum line is being blocked off by the fuel, which stops it from pumping. I'm basically going to remove the vacuum line and block it off, so it's just a straight flow of gas. I'm also going to clean my carbs, as I assume they are quite dirty and haven't been cleaned in quite some time (and flush the tank with CLR or lime away)