Thanks cbrbike awesome pictures

 

Although the slow jets only act for idle, or so we're told , they do in fact form part of the initial acceleration, only slightly but that small part of the flow prior to and during butterfly opening is crucial , if there's any free play in the accelerator cable you can adjust that , but it sounds like it's down to carb cleaning , especially the slow jets

 

That' very useful information mate I did not know about what the different Jets are used for although I did pull them all apart just last week and clean everything so I'm not really sure what' going on and yeah there is definitely no play in the throttle either this is a strange one /:

 

Backfiring sounds like dodgy fuel(I know about that); but do the least disruptive work first, go through it methodically.
Drain fuel bowls, and collect in jar see what comes out...examine....beads rolling around the bottom of jar =water .
Check state of battery, is it old, ie over 3 yrs.
Check to see if bike is earthed.

 

Ok mate no worries I'll go through that list and see what I come up with

 

My battery does actually look pretty old I think I might replace it but it is blank it has no writing on it or anything does anyone know what model battery I need to put in?

 

yes. the filter should be there. inside that there's a thin rectangular sponge which filters dust, insects etc. otherwise they would enter that part of the carb. here you can see it. for now you can put a thin sponge to the end of that hose and use a rubber band to hold it there.

 

Ok no problem sounds like a plan for now till I find a more permanent fix thanks very much for that

 

i think you are referring to a hard acceleration (quick acceleration) situation from idle.
if so you have to clean the idle circuit which includes the slow/idle jet, two slow/idle air jets and pilot screw. here's a good explanation from IDoDirt.

apart from that you have to clean these tiny little three bypass holes which acts as a transition from idle to mid range. spary some carb clean from the air jets side as well as from this side. also use some compressed air this is a differnt carb which i found from the internet but it's the same for our carb.


you have to clean the diaphragm slide itself (not the diaphragm). i use petrol. i'm afraid to use carb cleaners on rubber parts


also make sure these holes are not clogged. when you put a blower from the top side of the diaphragm you can feel the air coming out from these two holes.


then the carburetor walls where it goes up and down.


images were taken from the ineternet.all rights belong to their respective owners.

also apparently your bike is a CBR250RR(R) MC22 Fireblade, here's is the pilot screw turns for your bike. you can set it as an initial setting.

 

Wow that is unbelievably impressive explanation of everything I need to do I'm blown away mate thanks very much for all that im gonna get on it asap