FZRSupport: the FZROnline Archive

i know there are already lots of other carb questions on here but none exactly the same as my problem.

I seem to be getting very low mpg, like 35mpg!!! on a stock 1989 enging with 35K on it. The engine never needs any choke to start and can be difficult to start when hot, it generally idles at 1300 but sometimes riding through town when i stop at lights with the clutch in it runs at about 3000!!! then when i bring it back to 1500 with the clutch it stays there but settles again at the highter rpm next time i blip it.

Obviously the obvious thing with the poor mpg is a leak somewhere but ive had a good look and cant see anything, ive had the airbox off and the carbs dont look too gummed off but im nervous about strippingthem all out because i have nightmares of when i did that to my FZR250 about 8 years ago and lost all the bits (my workshop skills are much better now.)

I plan to sync them first of all, but as i dont have a guage just a universal balancer Balance the vacuum in two tubes at a time by comparing the force exerted on a ball bearing in a U tube.) i dont know which carb i should sink to.......

Thoughts ideas suggestions or directions to the how to carb thread that i cant find would be really welcome....

Thanks guys!!!

sounds like its running rich.
mine is doing the same currently. been to lazt to adjust it.
adjust your A/F screws.
what you do is turn them right (clockwise) until the screw sets and doesnt turn.
count how many turns you do so you know what its currently set at.
whatever your currently at, say about 3.5 turns out, then set the screws to 2.5 turns out.
you can do this and turn your motor on and rev it up.
if the rpms lag coming back down to idle, then its lean
turn screws in for leaner, turn them out for richer.
if its lean, then keep turning 1/2 turns at a time out till the rpms no longer lag.
then it shouls be set at a decent setting.

you sync carbs in this order.
1&2 get synced together.
3&4 get synced together.
1&2 & 3&4 get synced together as a set.

so you connect hose to 1&2. sync.....then 3&4, sync....then 2&3(or 1&3 or 1&4 or 2&4) sync and your done!

brilliant, i'll give that a go tomorrow and let you know how i get on.