high speed studder to a stall

I currently have 2 bikes, bike 1 is a 85 xj 700 maxim. Bike 2 is a 86 xj 700 maxim X. Bike 2 was purchased as a parts bike for 1 and ended up being a better bike than 1 at a fraction of the cost.....go figure.

Bike 2- After getting it home the first assigment was to evaluate weather to salvage it or part it, I decided it was worth saving. The carbs were frozen I could not twist the grip at all. Off came the carbs and (the bike came with 3 sets of carbs , the one on it and 2 extra sets that looked pretty fresh) on went one of the extras. It fired right up! off I went I was terring it up all day, it was running like a champ. The following weekend Saturday morning I,m blazing up and down the street when......it starts coughing, spitting and thrown up all over itself, what the!!!

Here's what I'v done and it still is NOT corrected.

checked vacuum from manifold to petcock
ran a torch cleanning tool through the jets
cleaned carb bowls
said a lot of prayers

Suggestions are welcome, thanks in advance

 

Gotta ask the obvious......... Is it out of gas?????? 8O

Wouldn't be the first one to tear things apart on an empty tank. :wink:

Is it getting fuel out of the petcock?
What condition is the inside of the tank?
Inline filter?


I'm thinking fuel blockage from some crap in the tank.

Seems strange it was running so well then so badly. Usually means fuel supply problem.

Put it on PRI and see if fuel is flowing. If it is then see if the bike runs on PRI. If it does then a petcock clean may be in order.

Presuming from the original carb frozen that the bike has been sitting for a while so rust in the tank may be blocking things up.

 

You mention that you cleaned the carb bowls. Given the possiblility of more gunk floating in from the tank, I would strip the carbs tops and bottoms and clean all of the jets. Get a good baseline clean and then proceed to install a fuel filter (clear is a great idea so you can watch for contaminates).