Starts with starter fluid, but won't hold idle

xs2Doug · Full Member Joined: Jun 01, 2006 Posts: 50

Hi,

Just got my 72 to the point where I can fire it over. Its a new project for me and the bike hasn't run in some time.

I went through each carb, each petcock and changed the oil. at present, I'm able to get it to fire over and can even keep it running by reving the throttle but it dies if I let it go below 3k or so.

not sure what to check first; set points, timing, valve lash, mess with the carbs, etc...

both sides do seem to be firing and I've got good spark on each plug.

Also, Do all of these bikes vibrate like mad!?! mine will back itself up about a foot each time I throttle it if I run it while on the center stand... a couple of the front mount bolts are not stock and need attention but man does it vibrate!

jayel

yeah they all do a little happy dance if on bare concrete, put a rubber mat down under center stand to stop it, inside of the front of the carb throat right by the top of the butterfly are 3 small holes and a slightly larger one, part of the idle/air circuit make sure they and your pilot jet are clear that may help your idle, the motor mount bolts should be right diameter to keep engine in correct alignment

grizld1

Set the valves, cam chain tension and ignition first, then dial in mixture screws and synch; valve clearance and ignition can impact carb function, so do those first.

xs2Doug · Full Member Joined: Jun 01, 2006 Posts: 50

ok, was able to get it to idle somewhat better although it still surges a little...

It doesn't want to idle down as far as the book says (1000-1200) without loping and/or dieing but I'll try setting the valves and timing, etc. as suggested.

How much effect do mufflers have on idling? I'm just running head pipes now... I'm assuming I'll have to get them on before everything is running smooth?

grizld1

Relieving exhaust and/or intake breathing has a major impact on carburetion--leans out the mixture.

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