Too rich?
 

Hey all just got my new carb on my magician and trying to get it dialed in. I noticed today when i went to start it today hadnt riden in a couple days used the choke got it started and i noticed my choke does absolutely nothing. When its idling i play with the choke and on full there is 0 change in rpms. If its cold i might have to use a spray of starting fluid to get it started then it idles fine and full choke has no effect the only info i could find on this said its possibly so rich that its not effecting but it should start fine..which it has trouble doing when its cold. Is this too rich of carb a bad thing? It runs and idles fine so playing with setting seems ??? But i want it to start righ up without having to carry around a can of spray. Advice? Would upgrading the electrics/battery/starter do anything for this?

General rule of thumb when it comes to the choke. At around 50 degrees or less it should be necessary to use full choke to start the bike, and how long full choke is needed just depends on how cold it is. Usually above freezing you should be able to switch down to half choke within 30 seconds to a minute at most. The colder it is, the longer it might take obviously. Above 50 to say 70 degrees, the bike should start with little to no choke. Even if full choke is needed to start, it should/will bog out very quickly if not changed to half choke. Even then, half choke is only needed for a minute or so and then it should maintain an idle with the choke off. Above 70, the choke really shouldn't be needed.

Too lean on the idle mixture will require more choke and for longer and make for harder starts when it's cold.

Too rich on the idle mixture will require less choke or no choke at all when cold, but in warmer temps the bike will be harder to start and require opening the throttle some for more air to get it to fire off.

No matter what the settings are, one thing to keep in mind is that until the engine gets warmed up, the idle will stay a bit on the low side due to the engine being cold. These don't have a bypass circuit or any sort of idle control, so it either requires nursing the throttle a bit to keep the revs up, or adjusting the curb idle speed with the knob on the side of the carb, and then re-adjusting once it gets up to temp.

Good info but let me rephrase i understand how a choke works so when my bikes idling and I play with the choke it has absolutely no effect and what I've read says that when this happens it's because it is so rich restricting airflow doesn't do much. Show the bike runs fine and idles fine after it starts up and the choke having no effect means something's not working right correct? And since the idle seems to be in about the right spot is it my air mixture that is off then do I have to play with the air screw? And lastly I was just thinking about it and how much does upgrading electrical and battery starter affect cold starts?

Ive got my after market carb on just trying to get it zeroed in like a laser!
On these bikes does it not matter, that is, if you havent ridin for a few days your going to have to nurse the throttle on startups till warm no matter what?

If it runs too rich alot it will wear out the rings and cylinder. Gas washes the oil off. That's why efi engines outlast carburated( no choke)

To answer your last question, monkeying with the electricals on your bike will have no effect on this whatsoever.


What kind of carb do you have? Some carbs use a true choke, i.e. a plate that rotates and physically blocks off some of the airflow going through the carb. Others, like the various Nibbi carbs (and "real" brand name carbs on many bikes, particularly Keihins) have a "choke" that is actually an enricher. Airflow is not changed when one of these is employed; rather, it opens a little port that allows more fuel into the mixture instead.


If your carb is one of the latter, and the enricher passages are gummed up or plugged, or you have some other mechanical issue with that system then it is perfectly possible that your "choke" is literally doing nothing. We'll need more info to make an accurate guess, though.

The use of quick start to get it running tells me your valves might be on the tight side ,and I don’t see a valve adjustment mentioned in any of your posts .The valves will disturb your tune and have you chasing your tail on carb things when in reality the carb is fine .

Interesting on the valves i have yet to do that. Bought the feeler gauges just was waiting...wanted to port the heads while i was down there but u dont need to tear up to do valves!

I have a genuine keihin pz30 and i am 99.9% sure it does not have an enricher. (I would have noticed it rejetting it right?)
Running a 110 main 42 jet (pz pilots are on a different sized scale for some reason) at 300ft. How do u upload picture that arnt teeny tiny?
Do any of you think i could be grabbing too much air, did an airbox delete with a 55mm diameter filter? Screw it id like to understand things better but i kept all my stock parts just incase. Guess u have to spend hours on end tinkering till its right

Definitely, adjust the valves. That's the number one problem when hard to start.

The PZ30 should have a traditional choke, yes. You can tell if you pop it off and look at it. The choke plate is easily visible in the inlet throat and is operated via the lever on the side. Enricher carbs typically have a plunger you pull instead.


I would ensure that your valves are in spec as Bruces has suggested before chasing your tail on other potential causes. These bikes typically leave the factory with the valve clearances way too tight (i.e. with none) which will cause your engine to run lousy and be hard to start. You can pick up a suitable feeler gauge set at Harbor Freight if you don't feel like waiting for one to show up in the mail.


Make sure your engine is 100% cold before checking and adjusting the valve clearances. Let it sit overnight, for instance.


FWIW, the traditional butterfly plate choke on my Bashan Enforcer does not change the bike's idle, either. That is usually an effect of enricher type carbs. What it does do, however, is make the engine misfire and stumble if the choke is closed and the engine is already hot.


If you want to post a picture on here that's bigger than a postage stamp I recommend uploading it to imgur or similar and just copy-pasting a link to it. That's what I do.

Picture posting methods

http://www.chinariders.net/showthrea...518#post369518

http://www.chinariders.net/showthread.php?t=14422

Postimage also works good and has the best picture quality

Thanks everyone good stuff. Ya even if mines warm full choke does nothing! Maybe theres a leak somewhere...goodthing i have plenty of starter fluid... freaking EVERYTHING comes loose on this bike just about every 20 minutes lol

One thing i did note though that i forgot to mention cuz its hard to explain without sound effects but im hearing a sound like a vaccum sound of something trying to pull or push (air or gas?) But then goes away and seems fine after a few seconds. Im guna work on it in a few hours ill post some pucs later.

This is my exact carb...actual pics otw

I don’t think that’s a genuine keihin carb looking at the pictures ,it looks like the $20.00 clones everybody is running and happy with .I don’t even see where it says keihin on it

I thot so too but its stamped on top. No enricher right? Normal pz30 with a standard choke right? Will link better pics soon

Yes ,normal pz carb with choke ,and no ,not original not even close .Many of the clones mark them ,first time I ever saw one marked in that area real or clone .Keihin is proud of their carbs and mark them (they cast their name on it ) on the body where the slide is ,so everybody can see who built it ,yours is marked where nobody can see it ,possibly on purpose so they can’t be sued ? I am sure it will work just fine .