Help needed... over heat/super lean??

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Sounds more like your pilot jet is blocked, Can you actually see through the pilot jet? If the mixture screw does not work when you try to adjust it when idling its a good sign the pilot jet is blocked, What fuel filter do you run?

Needle clip position changes the mixture as Rotn mentioned but if it did run fine at some stage there is no need to change it, That controls the mixture further up the revs
Pilot jet controls low rev mixture, Start with that

Idle screw all the way in thats extreme? It should be revving its tips off?
 
Sometimes the pilot jet can seem clear & have a hole but if it has a bit of build up/gunk it will do exactly as you mentioned, No idle & will not idle without the choke & will only run at high revs

Pilot circuit controls idle/low revs, This is where the trouble is, A fine piece of wire will clear the pilot jet, Also the actual alloy casting above the pilot jet can be flowing but clogged up, Make sure it is clear

No mention of a fuel filter also makes me think a fuel blockage in the idle circuit is very likely
 
Inline fuel filter fitted since kickstarter shaft replaced and removed to see if that was starving the carby.

The carby and jets were throughly cleaned, blown through and closely inspected so i highly doubt there is an issue with the carby.
But will remove pilot jet tomorrow and use oxy tip cleaner gently if will fit.

All i can think of now is if the valve lash need rechecking or something in the ignition side of the show.
 
Nah from what you have said it is very very likely to be the carb, Very hard to diagnose these things though through the interweb posts

I removed the carb on a bike a few times & blew through the jets each time with compressed air & put it back together & it would not idle properly & was a beach to start, I used a fine piece of wire & cleaned both the pilot jet & the hole above the pilot jet & now that bike starts cold near first kick everytime without the choke, It needed full choke before & used to pop & carry on even with the choke on & had a terrible bog when you blip the throttle

Runs sweet now with the pilot jet & hole in the carb massaged
 
Pull the fuel tap out and check the filter on the end of it. like thumpin :bump2:said its all fuel, maybe time for a new carb. sounds silly but pull the plug and insert it in the plug cap and kick the bike while holding the cap . had the same prob with bogging like you are on a customers bike
 
Sorry mate left that part out.....hold the cap with plug in it without earthing it out and make sure you can't feel any spark thru the actual cap that would arc onto the head when the plug is in the engine.
 
just try another carby. its not worth wasting all that time. a new carb will cost less than $100 and i bet anything that is the problem.
 
Well this is how today went...
Checked inlet vavle lash, was about .002 so corrected to .003.
Checked ehaust valve lash...was spot on.
Pulled carby bowl off and removed main jet and idle mixture screw and cleaned galleries with tiny lil oxy tip cleaner.
Drained fuel tank and removed fuel tap, internal screen looked very clean.
Took lead off plug and held while kicked over... shocks to the system lol.

Started bike... ran fine but still stalled when changing up gear.

So then removed fuel line and inline filter and fitted a new fuel line with out a filter...still the same.
Tried several different positions on ignition timing but worse so put back to original position.
Then tried a spacer washer under the needle e-clip... worse again so back to previous setting.

So then after sitting down and pondering I thought maybe its getting too much air without an air filter hence lean...
So fitted the melted filter with a filter skin to cover the burn holes as im still waiting for the new ones to come in.....

BINGO!!! runs like it had before i snapped the kick starter shaft!!
Runs like a dream!! :b_grind::b_grind::b_grind:

Even so im still considering a oko flatslide down the track maybe.
Thanks heaps for your help people!!:hail::hail::hail:
 
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sounds like the mixture screw needs to be turned back in, to 1 1/2 turns out.

when you are cleaning out the carb, are you taking the pilot and main jets out, and the needle and seat out, then blowing it out with air.

could be a chunk of plastic or ? sitting above the needle and seat, blocking the fuel flow, and restricting the amount of fuel getting into the bowl.

another thing, there could be a blocked hole in the main jet tube, or the pilot jet, (the tiny holes on the side of the jet) you will need to take them out to check it properly.

keep posting your results too, helps us to diagnose
 
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my mistake, i didnt notice the 2nd page of the thread, lol

can i say though,
i have never heard of having to run an air filter to restrict airflow to make a bike run better?
sounds like that carby has problems, or at least needs jetting.
and i've been playing around with bikes for 30+ years now.
 
Yep i agree 100% , being on the bottom needle position suggests rejetting but an OKO maybe the go before that happens.
Just for interests sake its running 100 main and 20 pilot.
 
my67xr said:
my mistake, i didnt notice the 2nd page of the thread, lol

can i say though,
i have never heard of having to run an air filter to restrict airflow to make a bike run better?
sounds like that carby has problems, or at least needs jetting.
and i've been playing around with bikes for 30+ years now.
Click to expand...

Extremelly common. Try to run a victor 160 lawn mower without an air filter. They wont start.
Years ago I had a z50 with a CT 90 motor in it. I could not get it to run. Took it to a bike shope and got it serviced and an airfilter and it ran perfect. Turned out it was the air filter not on it causing it to not start.
 
I have the same problem with back fireing, its got me stuffed, all the timing is perfect, the piston and rings are fresh the only thing I can think of is there is some wrong with the carby getting to much fuel? Any help?
 
aussie_140 said:
I have the same problem with back fireing, its got me stuffed, all the timing is perfect, the piston and rings are fresh the only thing I can think of is there is some wrong with the carby getting to much fuel? Any help?
Click to expand...

Read through everything written here and start your own thread. easier to solve 2 issues separately.
 
Ok finally got out for a ride and iv now found its running rich or at least the plug is black sooty looking after a top gear WOT run then motor cut.
Bike is rideable but very slugish and boggy with pretty much no top end.
So im guessing throw carby in the bin and get an OKO Flatslide.
I managed to put up with it for a couple hour ride but now wondering if ive glazed the bore due to the fact after the wash and blow off while kicking it over it didnt seem like it had the knee jerking compression it used to have.

Any advice on if i should try tune the 30mm fakuni or just spend up on an OKO and if anyone thinks i'll need a hone and new rings??
 
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