Bike has no power and will only run with choke on.

Energy One

smithman123

New Member
I have a 2004 mastiff that rode just fine a couple days ago and today it acts like it has no power and dies when I come to a stop. Will only run with choke on. Not sure where to look. Any help would be amazing or I'm going to have to sell this thing. Only has 6k miles.
 

Sven

Well-Known Member
I'd take a compression test and get that the fuck out of the way. I know it runs but there are only two (spark/fuel) left. Then I'd chase fuel next. Choke on says you have spark/compression. But using choke is for a bike sitting and it takes all three jet circuits to start and run with a 14.2 AFR.

So the low speed being the air screw using the start circuit for start and idle is more clogged if the choke pulls from the main jet to run the engine. If the main was clogged, you'd have a weak battery trying to start a fully clogged circuit(s). Ass me how I know.

Believe it or not, been experimenting with the brand name 'sea foam' unclogging jets, by running and letting sea foam to sit in the bowl and do its work.
 

Mikeinjersey

Well-Known Member
I have a 2004 mastiff that rode just fine a couple days ago and today it acts like it has no power and dies when I come to a stop. Will only run with choke on. Not sure where to look. Any help would be amazing or I'm going to have to sell this thing. Only has 6k miles.
Your carburetor does not have a choke. You have an enricher. The difference is that a choke blocks air from entering the carb which effectively increases the fuel mixture at startup. An enricher adds fuel when the lever is raised in order to add extra fuel at startup. Similar outcome but different approach to getting a richer air/fuel mix for cold starts.
Don't panic and sell your bike! Your issue is most likely a dirty fuel system. Check that the petcock is not clogged. Drop the bowl and clean out any gunk along with checking your jets and float valve. If you aren't comfortable with that the Sea Foam additive that Sven suggested may get you by. This guide may help you.
 

Attachments

Top