Tuning issues. Help please....

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dusty

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Hello people's, I'm ready to throw this dam carby in the bin but before i do that i have to all i can to save it. Here's what it's doing, my bike was running super lean n was stalling. So i had a go at tuning it, i can get close to full throttle now with it chocking n stalling before it was at around half throttle. I have turned the fuel/air screw to richen it up as far as it goes n wondering is there anything else i can do to get my bike working right again? I have also cleaned out the jets n the rest of the carby. The carby is a mikuni 26mm.
It runs good when i use half choke before i had to use full choke n it would still choke a fair bit. Can anyone help? :beerchug:

I'm ****ing over trying to tune this dam thing n ready to order a new one.
:cursing:
 
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so by tuning it you mean adjusted the pilot air screw??? have you changed main jets or needle height??

Do a big search on here and have a look around at what other people have done. If you dont know what your doing it can be difficult and frustrating, so read up and learn......

Adjusting the air screw is not going to change your top end a lot....
 
id be checking normal stuff..

fuel tank breather
valve clearance
exhaust gasket
spark plug
then manifold gaskets and air filer..
 
id be checking normal stuff..

fuel tank breather
valve clearance
exhaust gasket
spark plug
then manifold gaskets and air filer..

The breather is fine
No idea about the clearances as i don't have a feeler gauge
Have to check the exhaust
The spark plug looked like it was runing lean
Cleaned the filter n manifold gaskets r good.
 
so by tuning it you mean adjusted the pilot air screw??? have you changed main jets or needle height??

Do a big search on here and have a look around at what other people have done. If you dont know what your doing it can be difficult and frustrating, so read up and learn......

Adjusting the air screw is not going to change your top end a lot....
I have taken out the throttle cable out of the carby n i can c the needle n have turned it but it doesn't c to move up ir down.
Nope havn't changed the jets as i don't know what size mine r. All i could c on the main jet is the letter m n two square zero looking things n a number 1. The owner before me as messed around with the carby, so I'm pretty sure i just have to tune it.
 
take the valve covers off and try to rattle the valves they shouldnt move much at all [its a little more complicated than that just look it up there is a good guide in the how to section]
you should be able to get some feeler gauges for around 5 dollars or so
 
take the valve covers off and try to rattle the valves they shouldnt move much at all [its a little more complicated than that just look it up there is a good guide in the how to section]
you should be able to get some feeler gauges for around 5 dollars or so

Thanks 4 the help, I'm home 4 the next couple of weeks from work so i have got alot of time on my hands. Started it up before n yeah just chokes n dies. I'll try to c if the valves r loose n might order another carb while I'm at it. One thing I'm keen to try is change the fuel back to 91%. I was using that when i first bought my bike n it was running way better. I'm using 98% prumium atm.
 
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so by tuning it you mean adjusted the pilot air screw??? have you changed main jets or needle height??

Do a big search on here and have a look around at what other people have done. If you dont know what your doing it can be difficult and frustrating, so read up and learn......

Adjusting the air screw is not going to change your top end a lot....

Adjusted the needle height last night n it's hitting the rev limiter now just past half throttle. Still can't use full throttle tho without the choke turned on.
 
take the valve covers off and try to rattle the valves they shouldnt move much at all [its a little more complicated than that just look it up there is a good guide in the how to section]
you should be able to get some feeler gauges for around 5 dollars or so

The valves feel tight.
 
The valves feel tight.

Dude you really need to get feeler gauges, you should be checking the valve clearance's often, after each ride ideally, to stop yourself from destroying your engine. It's a small price to pay to save you having to replace valves etc.

If you have to have the choke turned on to ride then that is a clear indicator that it's running too lean. You will need to richen up your mixture through the air fuel screw, needle clip, or changing jets.

As has been said there are plenty of threads on here that explain all of this, search on here and you'll find out everything you need to know much faster.
 
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Dude you really need to get feeler gauges, you should be checking the valve clearance's often, after each ride ideally, to stop yourself from destroying your engine. It's a small price to pay to save you having to replace valves etc.

If you have to have the choke turned on to ride then that is a clear indicator that it's running too lean. You will need to richen up your mixture through the air fuel screw, needle clip, or changing jets.

As has been said there are plenty of threads on here that explain all of this, search on here and you'll find out everything you need to know much faster.

I'll get some feelers as soon as i can. I have adjust the fuel mixture screw n the needle clip. I can get 3/4 throttle now, it way louder n feels more snappyer. Can't wait to ride it. I'm in the process of ordering some jets 4 it atm. I have looked at some other threads n found some good info on tuning n simular issues. Thanks to everyone 4 the info.
 

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