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Posted

Hi, sorry forgot to mention that I purchased a new carb for it, so all should be clean and correct inside as its new. I can only get it to run on choke?

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Posted

lol Just cause it's new don't count on it being right best to have alook.

Try turning up the idle and adjusting the a/f screw 1/4 of a turn at a time untill the idle gets higher by it's self then turn down the idle to the proper rpm.

Posted

Right I have stripped the carb down and all looks good, no signs of any blockages. The current situation is that I pull the choke out (on), give it a kick, it fires up, doesn't idle very well but if you keep the revs on about 3000 it will stay there. Then if you push the choke in (off) it revs very high for a couple of seconds then the revs drop down to make it die??? Any clues what to do next?

Posted

hmmmmmWell it's def running out of fuel As Air head mentioned check the intake rubber spray some wd-40 while it's running and see if it runs better.

Also is your valve clearance in spec..002 -.004 thousand?

Will the bike stay running if you keep the choke on?

1) check fuel flow from tank

2) check fuel folw through the float/needle seat remove bowl and let it flow also check float height.Might be to low and not filling the bowl enough.

3) check air filter try removing it.

4)turn a/f screw out untill it will Idle.But mark it so you can put it back if needed.

Posted

So messed around abit this afternoon, put the old carb back on to test that one out, it works better, got it idleing without the choke on, running around 2k but still not happy with it. I could hear some slight hissing noise, sprayed it all with soapy water to check for air leaks but nothing. The head was smoking though, could it be the head gasket not sealed completely right do you think? When I did the valves a new gasket was used but it was the second time of removing the head.

Posted

my bike idles around 800-1500 depending on how hot the engine is... 2k sounds high to me. although it is a bitch to start sometimes so i guess it could idle a little higher..

Posted

Thank BenjiMC,I will mess about with the idle again. What about the smoking head, anyone got any ideas on this?

Posted

Never use water to test for leaks" :eusa_snooty: if it was to suck any in " its bang, bent conrod, use Wd40 it burns, ,, the smoke " is it puffs ? ie, under presure? or just burning off spilt oil, and the running without choke" is the air filtre attached, as will not run properly without,

if filtre is on, then its pilot jet,,

Posted

Black hat is right and wrong. Spraying soapy water on a naturally aspirated intake isnt going to tell you squat unless you have a fiberoptic camera in the boot as its going to suck in. But you would be hard pressed to get enough water in the cylinder with a spray bottle to "hydrolock" the engine.

If the smoke on the head is coming out of the gasket its a good bet that is your leak. If its coming off the surface of the head or the valve cover your probably just burning off some oil that was spilled on it during the build. A compression test will tell you if it is in the cylinder(i.e head gasket). If compression is in spec then you need to check that everything between the carb and cylinder is intact and airtight.

However. I think that since it changed between carbs you most likely just need to get the carb in spec. Get the A/F screw adjusted. Check the main jet, pilot jet, needle jet. If you have a factory air-box/filter, then getting everything back to factory specs is a great place to start.

Posted

Latest, yesterday morning I had it idling well and there was no smoke so I am gathering it was burning stuff off, it was just taking longer than I expected. Anyway, put new carb on and I had a slight air leak which is why it wasn't working, figured all that out and actually went up and down the street on it, I've had the bike a couple of months and never actually ridden it, I was buzzing. I was doing a couple of runs & then pulling the plug out to check the mixture, I got it to a point where it was brown. A good days work, I was ecstatic.

Then today, I come to the bike and can't even turn it over? I am so confused & stressed!

Posted

Sorry, I don't know what had happened overnight but it wouldn't fire up, I have spark but can't get it to fire up. Suppose I better check for air leaks again. I was just wondering, when i got the bike working yesterday i started the carb with very little air and kept adjusting more air through after ridding it. Will there be too much air running through when the engine is cold and not allowing it to start?

Posted

Do you have a fuel filter installed? If you still have spark and compression you probably don't have fuel now. Give her a squirt of of ether. If it kicks up for a second then dies. You need to figure out why you don't have fuel. Do you store it with the fuel shut off?

Posted

Got fuel, got spark but it won't start again. I haven't managed to start it since I went up & down the street on it. I 'm losing motivation with this bike now. I'm not sure where to go next with it, I'm running out of ideas!

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