So I need a bit of help with diagnosing a problem

The bike starts okay with choke on but requires either choke or throttle to stop it from stalling

I have cleaned the carburettor and it seems clean

The bike will run with and 15-25% choke

The other day I put it on prime and fuel came out of the air box

The idea also isn't very constant and fluctuates

What is the best way to diagnose the carby?

Also I have posted here before about a knocking sound, I have since checked the valve clearances and they're in spec I have also replaced the timing chain and checked lower end bearings

The sound is probably less of a knocking and an inconsistent vibration sounds like something is loose

Thanks

Your floats are either sticking, or have a poor seal at the O ring or poor seal at the needle.
Cool.
Buddha.

What Buddha said applies to the "put it on PRI and it overflows", that's leaking float needles.

The "won't idle without choke" issue is probably the pilot jets are clogged.

In both cases, the solution is easy. Get a rebuild kit with fresh pilot jets and float needle/seat assy, do a refresh of the carbs. Set float height correctly. You should be in good shape.

Quote from: mr72 on July 21, 2021, 06:28:15 AM
What Buddha said applies to the "put it on PRI and it overflows", that's leaking float needles.

The "won't idle without choke" issue is probably the pilot jets are clogged.

In both cases, the solution is easy. Get a rebuild kit with fresh pilot jets and float needle/seat assy, do a refresh of the carbs. Set float height correctly. You should be in good shape.

I really really dislike the chinese crapola rubber in the "rebuild" kits.

You may be able to clean the pilots using welding supplies cleaner wires or even a "jet cleaner" from one of the bike parts supply places like biker bandit (you should suggest they rename their company to Biker GS500 LOL) but the best bet is to actually see if the stock float needle is goobered up. If its fine, the problem is the O ring at the seat spigot. Get a new O ring and swap it.

An overflowing float can cause it to misbehave at startup too cos liquid gas is flooding into the chamber much like its running out the airbox, but while you're opening it up, might as well make sure pilots are clean.

Far cheaper and far better than swapping all the rubber for crapola chinese rubber.

Cool.
Buddha.

Any ideas what could be causing my phantom metallic rattling noise

Pulled the rotor and flywheel out from the starter clutch and it all seems to be okay
What should I be looking for in that area?

Could it be premature ignition?

I will post a video

Starter clutch noises are only at startup.
Backfiring into the carb would sound like a sneeze and usually happens on closing or opening the throttle. Exhaust back fire same thing, but sounds more metallic.
You may have an exhaust leak.
Or the dreaded cam shaft side drift - which cant really be fixed, its also not a problem. Just noise. Wait, what year ? In the 04 and later versions they put a 1mm shim to reduce the noise. You can get those in .1 mm increments to 1.3mm. So you can check and try that if its an 04 and later, else you're going to have to just ignore it.

Cool.
Buddha.

Here is a link to the video with the sound

https://youtube.com/shorts/Utv5jtka-GY?feature=share

Holy effing hell. That crrrrreeeeeee creeeeeeekkkkk while riding ? and it goes crk crk when idling ?
First try to separate where its coming from, and if its in gear or neutral or what ?
BTW also cam chain tensioner ok ? Did you check that ?

Cool.
Buddha.

Yeah cam tensioner seems okay? It winds in and out alright, when I press down on it there's almost no give/play

It's seems to be in the top somewhere

https://postimg.cc/zVbXzL8h
https://postimg.cc/Zv0YynN1
https://postimg.cc/9zNQHP5V
https://postimg.cc/YjSCPnPb

The first 2 are a part I found on the ground after taking flywheel and ring gear off to inspect
They all seem fine
I'll also post a video of the play in those gears

These another photo of the inside of the case where the starter clutch is
And a photo of what looks like a cam shim

https://youtube.com/shorts/CyvOQKQ86Z0?feature=share

Quote from: Bargarabandit on July 22, 2021, 05:43:35 PM
Yeah cam tensioner seems okay? It winds in and out alright, when I press down on it there's almost no give/play

It's seems to be in the top somewhere

Look in the valve cover. And look to see if the cam chain has a sag between the sprockets when you turn over the motor.
Also you check the oil ? Look for metal obviously.
That broken 1/2 ring sleeve, I dont know what it is, but really where is the other 1/2 ? And what socket is that ? 8mm ? or 10 mm - its for reference right.
You took off the rotor and starter clutch ? Oh wait a sec, look in the parts fiche, you may have the starter clutch and rotor etc making contact with each other cos you're missing some sort of spacer. But then that noise will be on the bottom end left not top.

Cool.
Buddha.

That's an 8mm socket

Just replaced the exhaust gasket, there was nothing there when I pulled it off

Drained the battery so gotta charge it up and see how we go