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Discussion Starter #1
I recently bought a Vulcan 900 custom for a sweet deal because it isn’t run. The previous owner said he rode to church one Sunday when he got out and went to leave it wouldn’t start. It has spark it’s getting fuel but it will not start it is backfiring back through the throttle body any ideas where to start.
Thanks
 

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backfiring back thru the intake is a sign of a lean fuel mixture, when the fuel mixture ratio is in the lean or in the rich condition, the mixture will not ignite in the cylinder chambers, which means the reason the bike is not starting is the fuel mixture is either too rich or in your case probably too lean cause it's backfiring thru the air intake, one of the causes of it being too lean is a air intake leak, meaning the mixture is getting too much air, probably and not saying in your case but probably could be caused by a hole or crack in the rubber intake boot, and since he rode it to church then when he tried to start it it wouldn't start probably means the bike was hot when he shut it off at church then with a quick temperature drop the intake boot cracked, i mean going from hot to cold too fast, you might have to check that rubber intake boot for a rip or tear or crack in it for an air leak meaning you will have to remove the gas tank to get a look at that intake boot just to eliminate it as the cause
 

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by the way, if assuming that the fuel mixture is lean meaning too much air, what you might want to try is this, put some gas in a spray bottle and remove the air intake cover and filter exposing the throttle opening, then try to start the bike as you spray a small bit of gas directly into the air intake, not too much gas spray but just a little bit, spray it in every other second and keep trying to start the bike alternating between more spray to less spray, if the fuel mixture is lean (too much air) then with you adding more gas spray it just might ignite and kick start the mixture, if it does kick over a bit by trying this then this is a sign that yes your non-starting motor is due to a lean condition
 

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1. What year is it?
2. How many miles?
3. Before squirting gas into the intake (dangerous), do some basic troubleshooting first.
 

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Discussion Starter #14
I put a spark tester in line and pulled the plug and held it to the frame it had spark. You can smell fuel when you turn it over and the plugs were damp and smelled of fuel when I took them out. I haven’t check fuel pressure I have to go get something to go in line to hook my gauge to. I tried to pull compression but my gauge is not working properly so I just went and bought a new about to check that.
 

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What I would do is make sure that the plugs are clean and dry, try a start and then check to see if they are fuel soaked.
 
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