madmadi

Yes this is normal.....dont screw it any further out than 2 turns.....is the needle adjustable? which needle you mean?

I have attached a photo of my plug. Please advise if it is good. Now, one more thing. When I adjust the air/fuel mixture screw- when I turn it IN the engine is slower when there is one turn out from the bottom, but from 1.5 turns out until the max out nothing changes. Is it normal? http://tinypic.com/view.php?pic=jqs028&s=6

Will do mate, thanks for that. I adjusted it without measuring it...

Tried from 1 - 3 turns, nothing changed, so it is not that. I think is something with the float....

Don't have the picture of the plug right now but I know it's ok. I have adjusted the carb float a little so it cuts off the fuel earlier and it seems it is better now, still choking but not so hard like before. It is definitely something with the carb as the problem started after disassembling it.

Hi mate, Plug colour is good, creamy white inside. I have adjusted the carb float a little so it closes the fuel earlier and it seems that it is better now, not so strong choking like before but still a little. Will adjust it a little more.

Hi guys, Just an update and another question.... Bike starts every time now, there was a problem with electricity, wet cables etc. So now it is fine. BUT Now when I ride more than 40mph sometimes the bike is "choking" like the fuel would be cut off for a moment, like you would hit a brake. I noticed that the it is worse when is windy. Is is possible that the carb takes some extra air (it would explain why is choking when is windy) or maybe there is some problem with electricity and when riding fast the spark is weaker? I check on two different spark plugs and two spark plug caps and there is still a problem. The thing is that this choking started after I took out the carb. The only two things I have changed are fuel/air mixture and bended a little float so it closes earlier (thought before that the engine won't start because too high fuel level in the carb) I have changed the air/fuel mixture few times, every time just a little but it doesn't help. Also, recovered float lever to original state. Any idea guys? Again, my theories are: - carb takes some extra air when riding fast - but the question is, through where the air is coming to the carb? - the spark is weaker and is breaking when riding fast (more resistance in the engine?) - rings are weared and/or compression is wrong - but it is not really possible as the problem started after dissembling the carb Thanks in advance, All best Martin

done. By the manual it should be 2 turns out. I tried 2 and 2.5 and no change

Hello again guys, Just an update, bike starts every time now One more question. When I ride fast (if you can ride fast on 125 ) around 50 mph there bike is like braking, choking or something as if it would not get a fuel or spark. It happens only on 4th and 5th gear and on above 6000rpm. When, while riding, I open the choke it seems to help a little. My theory is that maybe the engine/carb getting some extra air? The air/fuel mixture is set up as originally and apart from that I have only adjusted a little the float previously but put it back to original position. So, three options here in my opinion: Air/fuel mixture Float level Extra air from somewhere What do you think?

nah, under 1500rpm it dies, 1600rpm is absolute minimum and it is doing good on 1700rpm. I have setup 1800rpm as at the lower revs the headlight is dimming so battery is used.

yeah, posted it on 4 different forums as needed to fix it ASAP- I am commuting and cannot stand the buses... As you can see, there was a lot of different suggested solutions from many guys, but at least if someone in the future will have the same problem I hope he will find it here. Thanks again

Gentleman, I would like to thank you all for your help and time you have spent for replies to my post, really appreciate it. My bike is working now, it seems that there was a problem with the spark and moisture. I have dried the electric module and the HT cable, charged battery over the night and it is fine now. Also changed the fuel/air mixture a little (half screw turn) so there is less fuel, more air. Now, the only two things which changed comparing to before the fault is that now at high revs it doesn’t have the power (slightly only, above 9000rpm). as I have bended a little the carb float part so it closes the fuel flow earlier than before, so I think I will bend it back to the original position. My “neutral” revs should be 1800rpm and it is fine, the thing is that when I stop at lights and revs are going down they are going to 1500rpm for around 2-3 seconds and then going back to 1800- it wasn’t like that before- will it be carb float level or air/fuel mixture? I think the latter. I tried to close the carb float and see if the fuel is leaking but no, it is fine. So, so far so good, I am covering the bike for the night and outside work because it was all about the moisture. Thanks again for all your help Wishing you wide roads and rubber trees! All best, Martin

Not yet, but will do it today mate.

Checked all the cables yesterday, but no major flooding or something. I have just charged my new battery overnight as it was flat after trying to start the moto, took out the HT cable and the electric module to home for night so it can dry out properly, adjusted a little the float in the carb and will try to start the moto today. Will see. Fingers crossed!

Thanks, will read

Tried to start the engine with and without choke, short bursts and long, nothing...

Yeah mate, either this or the float problem mentioned by megawatt. Will do it today and share the output. Thanks for all of you guys for your time, appreciate it.

I think this is the most probable reason, my friend advised me about the same mate, so I will do it today. Thanks

Typo error, sorry, it is 12,000km Brand new battery, nothing else connected Just FYI, One guy just responded on another forum that: "The white stuff in rubber hose might be emulsified oil (presuming there is a breather hose connected into the airbox from the engine - this is done to reduce emissions). " It is normal starting noise, nothing unusual apart from backfire (sometimes)

yeah, sorry, typo error, it is 12,000 km. Don't have a compression meter. Changed spark plug cap to NGK just a week ago. Just spoken with my friend who is a mechanic, suggested that maybe the float inside the carb is not closing properly and it is too much fuel in it, thats why there is an explosion when trying to start the engine. There is some kind of rubber valve in the float and when is cold this rubber valve is too hard to open/close properly the fuel intake?

Hi guys, I need your help. Firstly my bike's details: Suzuki GN125, 2004 year, chinese version, 120,000 km done Carburettor Mikuni, as it is my first post cannot post any links, but if you need, just google brooksbarn and look for Suzuki GN125 2004- there is a picture of my carb. Mentioning it as I think I have a problem with carb...but you will now better Now the problem. Engine won't start from electric ignition when cold but it does start when pushed and it does start when engine is warm. New battery, new spark plug, fuel is going to carburettor freely (checked fuel tap filter), there is a good spark (taken spark plug out and touched to engine and pushed the ignition, good spark) So, there is a fuel going freely to carburettor and there is a spark. I have cleaned the carb, but to be honest there was no rubbish in it. There was some white stuff in the rubber hose which is going from air filter to carb, like soapy stuff. Adjusted a fuel/air mixture as was told by friend that maybe there is too much fuel and not enough air- when cold and rainy outside (live in Scotland) maybe the air filter is getting wet and there is not enough air going to carb? When trying to start the engine there is an explosion sometimes. Trying to start it with and without choke which is manual of course. Another thing, the fact is that the engine starts sometimes even when cold, I just observed that there is a problem when is wet outside (keeping the bike outside) The problem started recently, but as I said it sometimes starts, sometimes not. I use the bike everyday for going to work which is 8 miles one way. After 8 hours of work it starts most of the time, but after night it doesn't. Almost always it starts when pushed and from the 2nd gear. By the way, I don't know if that's normal but when I start the engine on the choke and it starts the revs are around 4000rpm but sometimes after 30secs, sometimes after 2 minutes revs going down to 1000rpm-1500rpm - does it mean that engine adjusting the choke automatically when warm? Doesn't it suppose to have big revs when choke is fully open, even when engine is warm? Now few possible reasons (in my opinion): Wrong fuel/air mixture (even after adjusting it- half rotation on the mixture screw) Bad compression Wrong valve settings (gaps) Ignition settings Blocked fuel stream from carb to engine (?) Choke problems Any ideas??? Thanks in advance, Martin