Whilst riding my bike, sometimes when i give it a real boot, it will lose all power for all of 1/10th of a second then take off like a bat out of hell. what i would like to discuss is whether this is something specific to my bike, or if all fizzer250's do it. I do realise things like this can happen on larger vehicles, as the carb operates on vacuum, but i did not think the smaller bikes were as likely to suffer from this considering the size of the carbs (although i may be mistaken) when you twist the throttle, the butterfly (or equivalent device) opens in the throat of the carbie (the venturi) you see a shift in where the vacuum is most intense down the length of the venturi. when you twist the throttle too fast, there is an extremely fast change in pressure inside the venturi, and so you lose that solidarity of vacuum. and so your bike bogs down for that 1/10th of a second until it regains the stability of vacuum. Am i the only one or is this normal?
I'm not really sure about mine, as I don't normally slam the throttle open - there's not much reason to?
I’ve heard of it on larger capacity vehicles and bikes so why not a fizzer. My 650 actually has dual butterflies to give a smoother throttle response. I don’t know to what extent the FI is used to rectify the problem like the accelerator pump on larger carburettors. Both of which the fizzer doesn’t have. The 250 4 is small engine, I found that I would use the gears just as aggressively as the throttle so it didn’t keep having to wind up into the power band. No doubt it is present on the 250 but as Casso said, not much need to be cracking on the throttle if you ride it right.
