Vaccuum problem

Bike: XJ Maxim 650.

Problem: turns over, doesn't start unless air intake is <u>blocked</u>

I'm guessing that the vaccuum required to suck fuel through the carbs isn't there. Once she starts she runs, and will keep running and start when turned off. When left for a good length of time, a few hours or overnight, she wont start. Any thoughts?

 

Enrichement Circuits in the carb/float bowl need to be cleaned.

 

In the interests of simplicity, would Seafoam do the job or am I spending a weekend tearing them apart and cleaning them?

 

For the price of a can, why not... if it doesn't work then you go farther.

How long has it been sitting?

 

It hasn't; The day it decided not to start I had put 30k on it. It's always been a good bike, just a real bitch in the mornings. Now, she dont do squat unless I plug the air.

(I don't usually post like that, but I have a six pack in me now .

 

Just a quick add on to Handover's post. Carbs were cleaned about a month ago, but I don't imagine it was a really thorough job. This bike runs smoothly and well once it has turned over although it idles a bit high. If we block the air intake on the carbs she'll turn over immediately. If we have to block the box (under the seat) she'll take a little longer to turn over. The screw on the underside of the carb is all the way out. I have tightened it a little in hopes that this will change how quickly it turns over, but must undo it once the bike warms or it idles too high. I really want to solve the problem properly if anyone has any thoughts?

Also, and this may be a completely different issue, she seems to be quite a pig on gas. A little history, this bike recently had an engine swap. The previous owner had air filters installed individually over each of the carbs. With the previous engine on this bike, I got about 20km/litre. With this new engine, I get about 13km/litre (about 28 miles/gallon).

 

Before the engine swap (end of February) bike had been sitting since October.