Engine (on occasion) dies (briefly) at high revs full throttle

Hi, i have an intermittent problem with my 1999 SV and was wondering where to start looking for the source of the problem.


On occasion when giving it full throttle at high revs, the engine 'dies' as if the kill switch has been hit or it has ran out of fuel (neither of those things have actually happened).

It dies for probably no more than a second, but it is long enough for me to bob my pants when overtaking.


The problem does not present itself at any other time, only high revs full throttle, and even then it only does it now any again.

I will try and have a look at it this weekend, where should i start?

Fuel lines, carbs. or electrics?


Cheers

have a good search through the postings and i'm sure you'll turn something up. does sound a teeny bit like carb or fuel prob's tho, and you say it happens on full throttle. is that only when you first crack the throttle wide open or is it more random than that?

It doesn't happen when i first crack the throttle open, usual i have had the bike at full throttle for a couple of seconds or longer. Generally (although i'm sure this is a coincidence) it happens after i have given it full throttle through first and second gear and the given it full throttle for a couple of seconds in third.

When were your carbs last balanced and valve clearances checked?

[flymo]

Sounds like fuel starvation. check your fuel filter and make sure there is no crap in the tank.

Originally Posted by branny

When were your carbs last balanced and valve clearances checked?

The carbs have been balanced recently, the valves have probably never been done (17k on the clock), but i can't see it being a valve problem.

Originally Posted by flymo

Sounds like fuel starvation. check your fuel filter and make sure there is no crap in the tank.

Thinking about it, that is almost certainly correct. A fuel flow problem could possibly only show up when at full throttle for a period as it would take a while for the engine to drink the fuel that is already in the carbs etc.



Cheers

[flymo]

yep, it happened to me a few years ago on a race bike. It would run like a charm for two laps then bog down when the fuel bowls emptied. By the time I reached the pits again it was fine.

Turned out to be crap in the fuel lines, it had mini filters in the pipes just before the carbs and they were full of garbage.

Originally Posted by lloyd_christmas

Thinking about it, that is almost certainly correct. A fuel flow problem could possibly only show up when at full throttle for a period as it would take a while for the engine to drink the fuel that is already in the carbs etc.



Cheers

Sounds right.
Time to drain the tank and take that fuel valve out.
Hope it sorts your problems

[Stu]

Rev limiter?