I have a Ninja 250 that is dual carbs. Since firing it up this year it has been running really odd. When I ride it hard under heavy throttle it performs pretty good. When I try to cruise at lower speeds it feels like it is surging. The rpm's are not jumping around but the surging is definitely there. I have added Fuel injector cleaner hoping this would help but so far nothing. Any thoughts?
Motorcycle running poorly - Bad/old gas?
- Thread starter spk2000
- Start date
- Status
Carbs aren't sync'd.
Having owned a bunch of motorcycles over the years, you need to clean your carbs. Take them off the bike, remove the fuel bowls, be careful with the floats, be careful not to scratch any jets you remove, use a can or two of spray carb cleaner. I doubt they really need synced.
its also very possible/likely that a pilot jet is clogged. make sure to inspect all of the tubes and jets. I had clogged pilot jets on one of my bikes - it took some careful cleaning with a fine wire - but it ran great afterwards!
i would try a heavy dose of fuel cleaner first, carbs dont just go "out of sync"
im sure a jet is partially clogged,
can of cleaner is the easiest fix
im sure a jet is partially clogged,
can of cleaner is the easiest fix
Also, carefully check the chain, for tension and condition. A loose chain, or one with tight spots, will cause the symptoms you've described.
Last edited:
I experience the same on a start up after letting the gas sit a long time, and mine is fuel injected. Dump the gas into your car, re fill with fresh, and see how it does after a 5 minute ride. Good chance the carbs could be gummed up. The harley I'm working on fired up after draining 6yr old gas, and no work to the carb.
Try a double dose of Gumout white bottle for 2 tanks of fresh gas.
Check your carbs vent tubes. I had spider webs in my vent tubes and my bike ran just like you described.
I didn't find the clogged tubes until after I rebuilt the carbs and changed the plugs.
I didn't find the clogged tubes until after I rebuilt the carbs and changed the plugs.
Originally Posted By: tomcat27
its also very possible/likely that a pilot jet is clogged. make sure to inspect all of the tubes and jets. I had clogged pilot jets on one of my bikes - it took some careful cleaning with a fine wire - but it ran great afterwards!
My bet would be pilot Jets, usually the first to clog due to the very small orfice. Fuel system cleaner might work.
its also very possible/likely that a pilot jet is clogged. make sure to inspect all of the tubes and jets. I had clogged pilot jets on one of my bikes - it took some careful cleaning with a fine wire - but it ran great afterwards!
My bet would be pilot Jets, usually the first to clog due to the very small orfice. Fuel system cleaner might work.
Cleaning carbs is a pain. SeaFoam works GREAT at cleaning needle and jet deposits and restoring function.
Napa has bottles on sale for $8 now. I think it's 1 oz/gallon. You will notice a difference within 1/2 tank. Do it for two tanks and you'll likely be good. It's been my go-to method for decades and has prevented the need to tear down many carburetors.
Napa has bottles on sale for $8 now. I think it's 1 oz/gallon. You will notice a difference within 1/2 tank. Do it for two tanks and you'll likely be good. It's been my go-to method for decades and has prevented the need to tear down many carburetors.
- Status
Similar threads
