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Twin cylinder flat spot


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Hi All


Its me the Virgin biker again.


I have a problem on my twin cylinder 125 and its this, it has developed a terrible flat spot so when you go to pull away it dies then gradually picks up again unless you give it plenty of revs...


I also noticed that if you remove the front cylinder plug cap and try and start it runs rather badly on one cylinder is this normal and how do i correct it..


I will says its more noticeable in rainy conditions.

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Hi All


Its me the Virgin biker again.


I have a problem on my twin cylinder 125 and its this, it has developed a terrible flat spot so when you go to pull away it dies then gradually picks up again unless you give it plenty of revs...


I also noticed that if you remove the front cylinder plug cap and try and start it runs rather badly on one cylinder is this normal and how do i correct it..


I will says its more noticeable in rainy conditions.

 

yes it is normal and to correct it put the plug cap back on lol


what bike have you got?

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Hi


Its a hyosung comet normally runs rather well, i have sprayed a bit of wd40 around.


Is it possible that it could be a fuel problem as it absolutely tanked it down last night and this morning


Thanks

1386060563_comet125.jpg.c50165778dda7f2674111c579797b776.jpg

Comet 125 mines gold

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im guessing this is carbed ???? :?


if so how many carbs has it got ?


if it has two (one for each cylinder) they will probably need balancing

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I'm still not sure why, but my bike has a very simular issue, and it's to do with carbed engines.


It's something to do with the way carbs work, perhaps as the throttle plate opens there is a place where more air can get in, but not enough fuel is drawn, i don't know.


But if i bring the throttlt of my bike just off idle, it very nearly dies, if not does die. My dad had a car that did the exact same thing.


If this sounds like it, you just gotta learn your bike, and know where it's flat spot is.

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I'm still not sure why, but my bike has a very simular issue, and it's to do with carbed engines.


It's something to do with the way carbs work, perhaps as the throttle plate opens there is a place where more air can get in, but not enough fuel is drawn, i don't know.


But if i bring the throttlt of my bike just off idle, it very nearly dies, if not does die. My dad had a car that did the exact same thing.


If this sounds like it, you just gotta learn your bike, and know where it's flat spot is.

 

that means the needle or jets need adjusting acordingly :)


no bike or car should do that

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Hi


Its a hyosung comet normally runs rather well, i have sprayed a bit of wd40 around.


Is it possible that it could be a fuel problem as it absolutely tanked it down last night and this morning


Thanks

 

How wet did the bike get mate?

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HI


I left the bike outside and forgot to put the cover on it....


It rained hard all bloody night

 

That shouldn't matter, bikes are surpossed to be weather proof.


I'd try fitting new spark plugs first before you try anything else.

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Hi I think i have found the problem


The bike has 2 carbs and the chamber leading to the second cylinder had an air leak int causing the mixture to be too lean.


Have plugged the suspected air leak and it appears 1000% better.


Kev

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