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Bike still wont run... rrrrghhh


yzf400
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Rrrrgggh. . .

my yzf400 is still being a pain in the **** I have been down local track n trail shop for some advise,

The guys says it cant be piston and rings cos there is loads of comp, i have changed oil, filter, spark, Taken carb of and give a good clean inside and out, I have checked spark and thats fine

It will only run for about 2 secs every 30th kick,

I gott bad leg now too :(

Can any one shed light on the situation?

Regards

James

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Rrrrgggh. . .

my yzf400 is still being a pain in the **** I have been down local track n trail shop for some advise,

The guys says it cant be piston and rings cos there is loads of comp, i have changed oil, filter, spark, Taken carb of and give a good clean inside and out, I have checked spark and thats fine

It will only run for about 2 secs every 30th kick,

I gott bad leg now too :(

Can any one shed light on the situation?

Regards

James

Sounds like what happened to my buddy's bike, I think his was a clogged filter. His bike would run only if the tank was almost full! Sorry I can't be of any help..

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Sounds like what happened to my buddy's bike, I think his was a clogged filter. His bike would run only if the tank was almost full! Sorry I can't be of any help..

I took air filter off today, still no luck :( thanks n e way :)

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Rrrrgggh. . .

my yzf400 is still being a pain in the **** I have been down local track n trail shop for some advise,

The guys says it cant be piston and rings cos there is loads of comp, i have changed oil, filter, spark, Taken carb of and give a good clean inside and out, I have checked spark and thats fine

It will only run for about 2 secs every 30th kick,

I gott bad leg now too :(

Can any one shed light on the situation?

Regards

James

If it runs briefly after loads of kicks the cold start (choke) isn't working, bet the plugs dry even after all that kicking.

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If it runs briefly after loads of kicks the cold start (choke) isn't working, bet the plugs dry even after all that kicking.

Plug is moist after kicking, fuel squirting on throttle, Not sure about the choke tho, I did take apart carb and clean it all today!

hmmmm. . . .

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Plug is moist after kicking, fuel squirting on throttle, Not sure about the choke tho, I did take apart carb and clean it all today!

hmmmm. . . .

After thirty kicks on choke it should be ringing wet....

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After thirty kicks on choke it should be ringing wet....

it pretty wet after loads of kicks, thats why i cant work out the problem, everything seems to be in order! is it a possible there is some thing bent inside engine?

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Sorry about all the threads, its doin my head in thats all!

All the timming shud be spot on, i made sure of that when i put head back together,

is there a possibility it sparking to late or early due to cdi magneto?

Im not sure how it works on a four stroke?

Regards

James

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I have a post on here about my bike only running for a few seconds then stalling everytime I try to start it. I just realized yesturday that my petcock was frozen so it was only allowing a small amount of fuel to the carbs. Not sure if you have the same problem, but its worth checking out.

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I have a post on here about my bike only running for a few seconds then stalling everytime I try to start it. I just realized yesturday that my petcock was frozen so it was only allowing a small amount of fuel to the carbs. Not sure if you have the same problem, but its worth checking out.

OK im gunna try not to sound really dumb here but. . .

Whats a petcock?

Regards

james

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I have a post on here about my bike only running for a few seconds then stalling everytime I try to start it. I just realized yesturday that my petcock was frozen so it was only allowing a small amount of fuel to the carbs. Not sure if you have the same problem, but its worth checking out.

Yes I did ask James to check out the fuel tap in one of the other threads, James I asked for a description of the tap ON OFF PRIME? have you tested the fuel flow to the carb is good?

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Yes I did ask James to check out the fuel tap in one of the other threads, James I asked for a description of the tap ON OFF PRIME? have you tested the fuel flow to the carb is good?

Yes, i have checked the flow, it flows very freely from tank to carb, it also squirts fuel into the carb when you twist the throttle,

I have been talkin to some people, and you may be right in it being a fuel problem :D

Still cabt get my head around why the guy i bought it from said it blew up?

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Yes, i have checked the flow, it flows very freely from tank to carb, it also squirts fuel into the carb when you twist the throttle,

I have been talkin to some people, and you may be right in it being a fuel problem :D

Still cabt get my head around why the guy i bought it from said it blew up?

Drain the fuel and put fresh in, including the fuel in the carb, you dont know if its good or bad fuel and its an easy thing to do, you havent seen any reason why it blew up, no apparent damage to big end, no seizure, no bent valve...who knows what he thinks 'blew up is' !. you said something about if you pressurise the tank its better...is that still so?

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Drain the fuel and put fresh in, including the fuel in the carb, you dont know if its good or bad fuel and its an easy thing to do, you havent seen any reason why it blew up, no apparent damage to big end, no seizure, no bent valve...who knows what he thinks 'blew up is' !. you said something about if you pressurise the tank its better...is that still so?

Yeh everything else seems to be in order! Yes if i pressurise tank it seemed to fire easier, but still only for a second or so, maybe 5 cycles of the engine ish. New fuel sounds like an idea!

I have been chatting to some guys on an MX forum and there saying carb floats and valves!

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All the above are possibilities, but dont forget that 'cynic' mantioned the choke, its going to be a b4strd to start if youre not using it or for some reason its not working, I dont 'know' your bike so try to fatom if the choke is good. also the usual way is to give little or no throttle when trying to start, is this what youre doing?

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All the above are possibilities, but dont forget that 'cynic' mantioned the choke, its going to be a b4strd to start if youre not using it or for some reason its not working, I dont 'know' your bike so try to fatom if the choke is good. also the usual way is to give little or no throttle when trying to start, is this what youre doing?

Ive treid it with and without throttle, I will check choke tomo cos im gunna strip the carb down over the sink he he!

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