pulse adrenaline bogging out at 8000 rpm

[Zorge]

Different profile needle?

[Dan SM]

Different profile needle?

tried putting it down to bottom notch with no luck aswell same thing bogging at 8000 rpm tried ringing local repair shop they said they dont do things like this so the rest of shops will probably say the same so now im stuck with the bike bogging at 8000 rpm

[Joshmakesnoise]

Yes theres only three notches and i tryed putting it up one but with no luck there wasnt a difference so i put it back in middle where is was before but im going to try put it down a notch as i found this diagram amd it says putting it down lets more fuel in and thats why im thinking its bogging out at high revs due to fuel starvation Attachment 17117

So when you say bogging you mean the revs aren't going past 8000? Bogging is caused by too much fuel and not enough air in the mixture. I assume you can walk the throttle open wide and there is also no bogging until 8000? How about in neutral? The same?

I recommend turning the air and mixture screw fully in and then screwing it out about 1.5 turns. See how it runs. My bet would be the needle pin or maybe the needle itself. Infact, what's the colour of your spark plug? Black is rich, white is lean. It should be a nice brown colour.

Anyway, I'll stop rattling on. I recommend dropping the main jet a size and see if it improves, let me know how you get on. If not, get the thing on the dyno, that way it can be set up properly. Josh

[Dan SM]

So when you say bogging you mean the revs aren't going past 8000? Bogging is caused by too much fuel and not enough air in the mixture. I assume you can walk the throttle open wide and there is also no bogging until 8000? How about in neutral? The same?

I recommend turning the air and mixture screw fully in and then screwing it out about 1.5 turns. See how it runs. My bet would be the needle pin or maybe the needle itself. Infact, what's the colour of your spark plug? Black is rich, white is lean. It should be a nice brown colour.

Anyway, I'll stop rattling on. I recommend dropping the main jet a size and see if it improves, let me know how you get on. If not, get the thing on the dyno, that way it can be set up properly. Josh

i just realized if i pull the throttle back slowly it goes past 8000 rpm just like normal but if i pull it back abit to quick it bogs out at 8000 rpm and doesn't go past it and yes its doing this in neutral is this a sign of too much fuel and its flooding? i just checked the spark plug and it was black but i didn't do a plug chop but i cleaned it there and put it back in and left it running awhile and theres no black looks the same as when i cleaned and put it in altho theres was a slight bit of liquid on it im assuming its petrol but didnt smell to strong of petrol i tried the needle but i'm open to try anything so i will try it again where do you recommend to put it it only has 3 notches for the circlip its in middle atm ? i will try screwing the fuel screw fully in then out 1.5 as you suggested and i'll let you know how it goes thanks.

[Joshmakesnoise]

i just realized if i pull the throttle back slowly it goes past 8000 rpm just like normal but if i pull it back abit to quick it bogs out at 8000 rpm and doesn't go past it and yes its doing this in neutral is this a sign of too much fuel and its flooding? i just checked the spark plug and it was black but i didn't do a plug chop but i cleaned it there and put it back in and left it running awhile and theres no black looks the same as when i cleaned and put it in altho theres was a slight bit of liquid on it im assuming its petrol but didnt smell to strong of petrol i tried the needle but i'm open to try anything so i will try it again where do you recommend to put it it only has 3 notches for the circlip its in middle atm ? i will try screwing the fuel screw fully in then out 1.5 as you suggested and i'll let you know how it goes thanks.

I recommend trying each notch to see if there is any improvement if it gets worse in the top notch try the bottom notch. This is all trial and error, if middle notch is best then leave it there. I would recommend lowering the main jet a size and see if it improves a little. If it doesn't then check the plug colour and look for a nice brown colour. If it goes white that means you're lean and that means you are starving your engine a fuel which will most likely end up with a seized engine of you keep riding it.

So as I say, go down 1 jet on the main and then check the plug colour and see how it rides. If it bogs less but isn't bogging as much try 1 size lower again. Keep checking the plug colour and also your insincts when riding. Let us know how you get on.

Josh

[Zorge]

Dan, we already disscused carb tuning on this forum: http://www.mychinamoto.com/forums/sh...e-Basics/page6

Also, not once emerged link to PZ carb tuning - http://www.walbro.com/media/22805/PZ-Tune.pdf

[Dan SM]

i tryed a thing online and it said 'does it run better with the choke on at full throttle, if yes then
1. your getting to much air
2. your fuel flow isn't good enough
3. your main jets to small
i tryed this and it does run better with the choke on and the link to PZ carb tuning that you sent says the same on symptoms of running lean if it runs better with partial choke on, so im thinking the bikes running too lean so if i put the the circlip on the jet needle down to bottom notch (there only is three and its in middle) and screw the fuel screw out should that richen the carb out enough or would i need bigger jets again?

[Joshmakesnoise]

i tryed a thing online and it said 'does it run better with the choke on at full throttle, if yes then
1. your getting to much air
2. your fuel flow isn't good enough
3. your main jets to small
i tryed this and it does run better with the choke on and the link to PZ carb tuning that you sent says the same on symptoms of running lean if it runs better with partial choke on, so im thinking the bikes running too lean so if i put the the circlip on the jet needle down to bottom notch (there only is three and its in middle) and screw the fuel screw out should that richen the carb out enough or would i need bigger jets again?

If you're running lean then your plug would be a white colour or a light colour, not black. Try a new plug in the bike and check the colour again. Or post a picture, but if it's black im saying too rich.

[Dan SM]

If you're running lean then your plug would be a white colour or a light colour, not black. Try a new plug in the bike and check the colour again. Or post a picture, but if it's black im saying too rich.

when i first done the plug check it was black but that was the plug in it before i done the changes in jets, airfilter and exhuast i took it out cleaned it and done a plug chop and when i done that the plug was the roughly as clean as when i put it in but there was a liquid residue on it but didnt smell of petrol

[Zorge]

You "tryed a thing online"? Not gonna work - you have to get your hands dirty.

BTW, in Chinese online shops you can get cute CV carbie for "Suzuki" clones for 20-25 quid.