carbs cleaned, valves adjusted - still not easy to start

[lilbilly]

Carbs have been cleaned, valves have been adjusted, have stock airbox/airfilter, checked for leaks in the boots by spraying carb cleaner around them while idleing - nothing.

But it still seems slow to start. It's been a little cool lately (mid 40's at night 60's in the day) and even with full choke it will turn over, but dies if I don't give it throttle, did the same at half choke and no choke at all.

After giving it steady throttle for a minute or two, it would idle just fine but would still be real sensitive and want to die when in first gear and pulling to a stop or pulling away. After a few minutes of riding, it's fine.

Any ideas?

Also, white smoke when revved until warm. Is that okay?

I tried to search, but didn't seem to find the right question/answer combo. Thanks for your patience with me and my 650g.

[greg78gs750]

did you double check the float height? i ask because on my new honda i didnt, and couldnt get it to start up after a rebuild. tooke the carb back off, checked it, the height was off, fixed it, and she fired right up. i am by no means any kind of authority, just a thought....

[chef1366]

Are you getting good voltage at the coils?

[almarconi]

tooke the carb back off, checked it, the height was off, fixed it, and she fired right up

Just out of curiousity, were they set too high or too low when you had the no start?

[Nessism]

Shimming the needles and opening the pilot screws some might help.

[nisom512]

1. did you fallow the carb rebuild guide?
2. did you get these www.cycleorings.com and intake o-rings?
3. have you done the coil relay mod(really easy....;once you understand it)
4. from what you said it sounds like it starts right up. your problem really sounds like from your discription that you are having problems keeping it running. what is your idle screw at I didnt know I had one till someone told me.

hope I helped
Jake

[lilbilly]

Once it warms up, it idles right around 1100 rpm. Idle screw should be set right. If I open it up anymore, once the bike gets warm it idles at about 2k or more.

[Nessism]

Once it warms up, it idles right around 1100 rpm. Idle screw should be set right. If I open it up anymore, once the bike gets warm it idles at about 2k or more.

Sounds like you need to open the pilot screws to get that higher idle and then set the idle back down with the throttle stop screw. Opening the mixture screws will richen up the mixture which will reduce the cooled blooded tendencies.

[greg78gs750]

Just out of curiousity, were they set too high or too low when you had the no start?

too high. so they were only letting a tiny bit of fuel into the bowls before the needle valve shut off the flow. actually, the po (or, more likely, the guy before him) had installed the floats upside down, then wondered why the carb always overflowed. i put them in right side up, but stupidly didnt check the level before i installed the first time. luckily, only one carb on this bike!! anyway, when i corrected the error, vroom!!!

sorry bout the little hijack, and im sure this isnt your problem...

[lilbilly]

Sounds like you need to open the pilot screws to get that higher idle and then set the idle back down with the throttle stop screw. Opening the mixture screws will richen up the mixture which will reduce the cooled blooded tendencies.

So once I set the pilot screws, I'll be able to turn the throttle (idle) screw down? Because right now the idle screw is in the perfect spot - one bump to the right and idle is way too high, one bump to the left and its barely staying alive.

Is there a pictorial for this procedure or is it pretty simple?

[Nessism]

So once I set the pilot screws, I'll be able to turn the throttle (idle) screw down? Because right now the idle screw is in the perfect spot - one bump to the right and idle is way too high, one bump to the left and its barely staying alive.

My suggestion is to set the pilot screws to 2.5 turns from lightly seated on each carb.

Start engine and adjust idle to 1200 rpm or so

Start tweaking the pilot screws inward until you can sense the idle dropping, and then open up the screw to increase the idle speed - stop opening the screw when further tweaking does not increase the idle any further. Take a mental note of how far open the screw is at this point.

Continue to adjust the other carbs - they all should wind up in the same relative position as each other. You may have to adjust the idle back down during this entire process.

Last step is to set the idle speed back to where you want it.

Keep in mind that the carbs need to be vacuum synced in addition to this adjustment. If your idle speed is fluctuating a lot, your carbs may need to be synced.

Good luck and hope this helps.

[lilbilly]

My suggestion is to set the pilot screws to 2.5 turns from lightly seated on each carb.

Start engine and adjust idle to 1200 rpm or so

Start tweaking the pilot screws inward until you can sense the idle dropping, and then open up the screw to increase the idle speed - stop opening the screw when further tweaking does not increase the idle any further. Take a mental note of how far open the screw is at this point.

Continue to adjust the other carbs - they all should wind up in the same relative position as each other. You may have to adjust the idle back down during this entire process.

Last step is to set the idle speed back to where you want it.

Keep in mind that the carbs need to be vacuum synced in addition to this adjustment. If your idle speed is fluctuating a lot, your carbs may need to be synced.

Good luck and hope this helps.

Carbs were in sync as far as I could tell a few weeks ago when we adjusted the valves, we set up the carbtune and they looked great. I will check basscliff's page as I'll need a picture tutorial to figure it all out...I'm a little slow on mechanics.