Running issue scooter left for 2 1/2 years By gman1234 (Read 628 times)

[gman1234]

Hi all, i'm after some help.
I have a Yamaha Cygnus which I haven't use for over 2 years. I ve started to try get it back on the road, brought a new battery as old one was dead and wouldn't hold a charge.
I manged to get the bike to fire up using kick-start and also on the button. The issue is that it runs for about 10-20 seconds the dies. The only way to keep it going is to give a little throttle but as soon as i let go the engine dies. So it wont idel.

Any Ideas appreciated

[cyborg]

My money goes to carb varnish and plugged up jets,,, clean the carb real well paying close attention to all the little orifices ,, should purr like a kitten after that I would think

[gman1234]

Hi can I ask why it starts if the carb is blocked?

[cyborg]

Idle jet / circuit is the culprit here but I'd go thru all of it if I were you so you can enjoy riding instead of pulling it apart several times

[gman1234]

Will I need to take all apart? Do I use carb cleaner? And what about fuel filter?

Thank you for your quick responses.

[cyborg]

You at least need to get the carb off and take off the bowl and inspect all the jets ,,, I'm sure you will find dirt& varnish,,,, and yes use carb cleaner

[gman1234]

Thank you I will give it ago.

[cyborg]

A side note if you've never done any engine work before take pics of your disassembly process so you'll remember how to get it back together and as a double side note use a sharp fresh Phillips driver on this bowl screws they are tighter than tight and somehow the Asians figured out how to make screws and bolts out of butter

[trashtruck12172]

after you've done like cyborg suggests, i would recommend replacing the spark plug, air filter, and all the other pm stuff, checking the air filter and muffler for critter leftovers and finally consider adjusting the valves.

[gman1234]

Okay will do. And will do suggested other bits. Thanks will update when done.

[cyborg]

You will be very happy if you do as trash says,,,most of these scoots just need a little tlc,,,most buy them run them till they stop then forget them

[gman1234]

Hi, brought some carb cleaner, thought I try starting it.fired and is running fine.

[trashtruck12172]

carb cleaner, seafoam and similar items might get it started and running but are no substitute for a thorough cleaning.

[gman1234]

Didn't use it but if plays up again then I will.

[jct842]

at least put a little seafoam in the gas tank.