I put on my lunchbox, and now its idling Fine , but it makes this spitting sound , like a tiny shot of air , every once in a while , its sorted out the Exhaust , now its not got smoke coming out of it , and it sounds alot better in idle , but i ve never heard it making these Spitting noises , and the odd Knocking Sound ? any ideas , because i think if i cant work out what it is , ill remove the lunchbox and put the stock filter back in ,

Thanks

Jay

Edit: i found the source of the Spitting sound ,



coming from the tube in my hand ,. otherwise its working fine , its hanging Ever so slightly , so i think ive got to do some adjusting on the mixture screws and the idle screw , as once it was well out and would idle at 4000 , then i dropped it down , then it would hang a little, then i adjusted agen , and it went away

Thanks agen!

ran my bike today because it started raining , and it didnt pop or anything , its almost like its sneezing , i can feel the air coming out of it when its idling , its very confusing ,.

Sounds like it's running really lean. The hanging RPM and poping can be caused by it running lean. The airbox muffles some of the sounds too so now with it off, you may just be hearing thing that were muffled before

You probally won't be able to take care of it with the mixture screw. You may be able to get it to idle alright, but you need new jets to richen it up across the RPM range.

Check the wiki and search here for more jetting info for your setup.

Its been Rejetted . im not sure what tho , but its always run really really rich ,

its never made a poping sound before , and it hangs slightly , like , ever so ,

i dont want to open the carbs or nout , coz i wont beable to no mess it up ,

it still doesnt need the choke , starts first time ,and idles smooth in cold weather..

Edit: It Idles Bang on 1200 . its fine like that

Did you cap off that tube?  That would be your source of air causing the left carb to be lean, and seriously unbalances the vacuum between carbs.

Where you do have the hoses coming from the tank routed to?

i dont scratch , i just put on the lunchbox. and they was dangling , ive started the bike maybe 2 times, is it ment to be capped? . as in something blocking it ?

Cheers Buddy

Yes, absolutely!

saying that , when i had my finger over it , the bike sounded fine.. mhmm but i thought i was being dumb.. clearly , i was   

Thanks Buddy!

any ideas what to use?

Spare bolt laying around, maybe, one of the mounting screws from the airbox.

Isnt' that the diaphragm vacuum tube to the petcock?  What's holding the petcock open?

the one in my hand is coming from the left carb , no where near the tank

He means to a frame-mounted petcock, on U.S. models it has a diaphragm that only allows fuel past if vacuum is drawn on the other side by a running (or starting) engine.

ohhh, i seee

Thanks tho buddy 

Yeah, attach the tube in your hand to the frame mounted petcock, its the vacuum line that allows the petcock to open to allow fuel into the carbs when the bike is running. Then when you turn the bike off, the vacuum is gone, the petcock closes and stops fue flow to the carbs.

The sneezing sound you hear is it doing a lean backfire up through the carbs, and its a good way to damage the diaphrams in the carbs, so hurry up an do it.

Its Sneezed About 6 times in total. yea i dont want to mess the carbs up at all , after the first 2 , i stopped it , then i had to find the problem , i dont think theres any damage at the moment , sounds fine