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Hey whats up guys,
Ive delt with it all season but now the off season is approching and i should check this out.
Cold start, choke open, two throttle twists and i hit the start button.
it sputters for about 7 seconds it starts running fine usually. Sometimes it cuts out.

I have twisted the carb to spray cleaner in it etc etc. I feel its the carb since i shimmed the valves last winter. Im hoping its a jet fix i can leave the carb in and do. If anyone has experienced this let me know some solutions you tried

Thanks so much

Paul

Hi Paul,
Has it always done this or is it something new.
Please include your current jetting.

I would check the valve clearances first.
How old is the spark plug.

First guess is a partially obstructed pilot jet. When you twist the throttle and let the accelerator pump squirts extra gas, you have provided just enough extra gas to allow the motor to start and run, but not enough to overcome a plug and keep running.

This isn't a rare condition, you get to deal with pilot jets for the entire life of a carbureted bike that isn't ridden regularly. I keep a handful of new ones around. This is a huge complaint in the spring as bikes are recommissioned from winter storage.

I would also check for an unrestricted fuel flow. Put a catch container under the bike and loosen the drain screw at the bottom of the carb bowl, and make sure that you get a continual flow for a few seconds.

Make sure you have a #45 pilot jet, and the fuel screw is about 1 7/8 turns out. While no setting is perfect for every bike all of the time, those settings will allow any 450 to start and run decently.

Thanks for the replys,
I bought the bike last winter and it sat for awhile the owner said. I did the valves last winter, i will check em again.
Im going to have to pull the carb and see what jetting is in there.

Im also going to order some main pilot jets

So i got into the carb today and pulled the pilot jet out (flat screwdriver ) it was in pretty tight, but it looked clear. Should i just order a new one? Its a 45
The plug end was pretty white which means lean?

I cant get the main out cause i believe i need a 6mm. The instructions said 8mm but that is way to big. Any tips ?
Edit: just f
Got main jet out with 6mm it says 142 on it thats to lean?