01-11-13, 12:02 AM
Hiya,
My Yamaha was not used for almost 2 weeks, then 2 days ago I've got the parts, replaced some and went for MOT. Everything was fine till today.
I've went back from a trip, it has no power and didn't rev on gear higher than 4k, if you open throttle more than 1/4 it's starts to splutter, but it splutters very gently, like it was planned or ECU programmed. You just need to give it less throttle and it does not splutter.
It has no power to go on hill higher than few %, also won't go faster than 50mph.
I can rev it without gear till 7k rpm, but the vibration and noise is very bad.
Since there is no magic there can be 2 issues, fuel or ignition, right?
I was trying to remove spark plug cables separately then start engine, but engine runs much worse even If I remove one of them (so I assume that it's not related with just 1 cylinder or 1 faulty spark plugs).
What you think I should check next?
I know that carb sync and valve clearance it's important, but I don't think that such a power drop would happen after 2 days. I will do it in a next few weeks.
I've 4 guesses:
a) Water in fuel (have issues with tank drain pipe, which is blocked right now to not leak), but I don't think that it would happen in a 2 days.
Motorcycle was running well after 2 weeks of resting, so 2 days are not so much?
b) Coil/coils?
c) Fuel pump
d) Is there ECU or something like that to check?
What's your guess and what's the way to check it? I've most of necessary tools and multimeter (to check voltage, resistance etc.)
Thanks guys
My Yamaha was not used for almost 2 weeks, then 2 days ago I've got the parts, replaced some and went for MOT. Everything was fine till today.
I've went back from a trip, it has no power and didn't rev on gear higher than 4k, if you open throttle more than 1/4 it's starts to splutter, but it splutters very gently, like it was planned or ECU programmed. You just need to give it less throttle and it does not splutter.
It has no power to go on hill higher than few %, also won't go faster than 50mph.
I can rev it without gear till 7k rpm, but the vibration and noise is very bad.
Since there is no magic there can be 2 issues, fuel or ignition, right?
I was trying to remove spark plug cables separately then start engine, but engine runs much worse even If I remove one of them (so I assume that it's not related with just 1 cylinder or 1 faulty spark plugs).
What you think I should check next?
I know that carb sync and valve clearance it's important, but I don't think that such a power drop would happen after 2 days. I will do it in a next few weeks.
I've 4 guesses:
a) Water in fuel (have issues with tank drain pipe, which is blocked right now to not leak), but I don't think that it would happen in a 2 days.
Motorcycle was running well after 2 weeks of resting, so 2 days are not so much?
b) Coil/coils?
c) Fuel pump
d) Is there ECU or something like that to check?
What's your guess and what's the way to check it? I've most of necessary tools and multimeter (to check voltage, resistance etc.)
Thanks guys