Still having problems

[Islandsteve]

My bike will not idle without me playing with the choke and throttle. Bike starts full choked at first idles very high then I turn choke down a bit the bike revs down substantially then picks up revving very fast again, then I turn the choke down again a bit and the bike revs down then starts idling fast again...repeat repeat etc until choke is starting to open completly then the engine will die without me reving it up with the throttle. Vrm vrm vrm vrm and the choke can be off completly. As soon as I quit revving with choke off it dies seconds later. When it is about to die I have to be carefully not to give it too much throttle too immediatly cause it will die, I have to start with blipping.

[nomedia="http://www.youtube.com/watch?v=Dc9WhrCjc0I"]YouTube- Broadcast Yourself.[/nomedia]
-WTF!!! cant name it anything but YOUTUBE-BRODCASTURSELF> how lame. shi**y coding.


This is a video I made yesterday before fixing The missing plug in my airbox drain tube which made a bit of a differance. I made sure all 4 cylinders were igniting and they were.

I had just installed a newer carb stack on the bike and newer airbox with new emgo filter. I suspect a vacume leak is probable at my intake boots. I have yet to sync these carbs to my bike because 1) I am waiting for my new cpu so the tach will work and I heard I should sync at around 1800rpm or so, might be wrong on that number. And 2) cause I can't even get the bike to run smoothe enough and consistantly enough to check the vacume I don't think.

I wanted to make a movie with better sound quality and not in my echo'ing workshop but I forgot my camera at my girlfriends house rrrr... Gonna try again tomorrow.

Would a mod please move this thread to the Mechanics 101 section, I just noticed I should probably have been posting all my bike problem stuff there instead of here...im a smrt cookie. Thanks

[kevin2502000]

Yeah I really couldn't hear much but it you have to open the throttle to get it too restart then its very rich. Are you sure the carbs you bought are stock and not a jet kit? I think it's flooding out.

[Islandsteve]

Yeah I really couldn't hear much but it you have to open the throttle to get it too restart then its very rich. Are you sure the carbs you bought are stock and not a jet kit? I think it's flooding out.

I don't have to open the throttle to start it, if thats what you meant. I don't think it;s flooding out cause when I actually give it gas and rev it up it does fine. But as soon as I let off that gas it starts to die out... The bike will run fine on full choke but idles really fast and I dont want to kill my engine so I turn off the choke a bit, give it some more air and the idle slows down, then up again, then ill turn the choke off more thus giving even more air and this is when the engine wants to die. Would any of this mean it could be running lean? Or maybe just one or 2 of the carbs are running too lean cause of a vac leak or somehting...

I am not sure about the jetting. I will check that soon if I don't get her figured.

Ill make better vid tomorrow

[kevin2502000]

AN easy way to see if it is lean it start it up and use your hand as a baffle over the airbox opening. If it runs better by covering the hole some, then it's lean. ( You are effectively changing the mixture by reducing the air). If it dies out immediately it's probably more on the rich side. Your plugs will tell you which way it is also.

[jetmerritt]

Hey Steve did you bench sync the carbs? Basically get the butterflies as close as possible with a drill bit or something.
If you haven't synced them and they are new to you carbs, they might be out and messing up your idle.

You can't adjust up the base idle at all eh?

[Islandsteve]

AN easy way to see if it is lean it start it up and use your hand as a baffle over the airbox opening. If it runs better by covering the hole some, then it's lean. ( You are effectively changing the mixture by reducing the air). If it dies out immediately it's probably more on the rich side. Your plugs will tell you which way it is also.

I will try this experiment tomorrow, sounds like a good idea. Will my plugs be like white if its running lean and black if is running rich? and brown or something for happy plugs? I thought i heard something of that mention.

Hey Steve did you bench sync the carbs? Basically get the butterflies as close as possible with a drill bit or something.
If you haven't synced them and they are new to you carbs, they might be out and messing up your idle.

You can't adjust up the base idle at all eh?

Nah I cant change base idle with idle screw very effectivly, it doesnt do much i still need to blip the throttle and fiddle the choke, or just open choke all the way and keep crankin on it. Or just leave the choke fully on and watch it rev itself to death.....

I did not bench sync the carbs, I will do this as well as pulling off floats n checking jetting and maybe clean them if i have the patience. When bench syncing should I just turn in the idle screw a bunch to lift the butterflies up while i adjust or whats the procedure here?

[kevin2502000]

Well since it's not running very long I withdrawl that test for the plugs. It needs to be running long enough to keep them heated up.

[Islandsteve]

Well since it's not running very long I withdrawl that test for the plugs. It needs to be running long enough to keep them heated up.

so they need to be hot when looking at them?

[hardlydangerous]

The enricher does not affect the amout of air you engine gets it simply dumps raw unmettered fuel into the carbs...
Start the engine and try to maintain a 1800 rpm or so fast idle using the choke for aprox 30 seconds or so.
No need to touch the throttle, you should not be revving the bike while the engine is warming up anyway and its not going to respond well to throttle.

[Islandsteve]

I wasn't reving a
cold bike, I let it warm up first. I'm just saying once I start to turn the choke off the bike will die unless I rev it...

Chokes do cut off air, or "CHOKE" the engine. Edit: I now actually understand the diff between dinky 2 stroke weedeater carb chokes and full blown enrichiner circuits.

[scottynoface]

Chokes do cut off air, or "CHOKE" the engine.

Um, no. The enrichment circuit dumps fuel into your carbs, that's why it's rich, not because it chokes off the air...

[Islandsteve]

Um, no. The enrichment circuit dumps fuel into your carbs, that's why it's rich, not because it chokes off the air...

Oh well I had no idea. Lol. Thanks for the info, I thought that the choke just worked like a good ol' choke...

[kevin2502000]

Oh well I had no idea. Lol. Thanks for the info, I thought that the choke just worked like a good ol' choke...

Not to be confused with choking your chicken

[Islandsteve]

Not to be confused with choking your chicken

Lol well I've got a bunch of diagnosing to do I guess, why has everybody been calling this "enrichment circuit" a choke? Is it just like another type of choke? And does the enrichment circuit dump fuel through the pilot circuit into the engine?

[kevin2502000]

It's one and the same. Choke is the dumb term that everbody uses. If you want to sound schooled say "enrichening circuit". When you move the choke cable to full choke it is enrichening your mixture or making it rich.