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A question for all you guys racing with Flat Slides & who are running a ram air set up. After a race or practice session do any of you guys find some raw fuel in the bottom of your ram airbox? I have been experiencing this and while its not alot of fuel, the possibility of a fire is pretty concerning. I know my TZ 250 had a lot of blow back on the over run but I am curious about the ZXR. Thanks in advance fellas.

i dunno bout the flatslides, but i get petrol in my airbox from the cv's. does'nt worry me really.

This is quite common with all carbs due to cam overlap. You may want to just check your cam timming but I would say it is OK. You can also get double carburatoin from this at certain RPM's so do you have any significant flatspots. cheers

regards TK400

Thanks for the reply's fella. I thought it was probably nothing to worry about. The thought of my bike going up in flames is horrendous.

decent trumpets realy help this alot, the fuel vapor stays in the trumpet and thus become part of the tuning, ( this is one of the reasons trumpets are good for a "tuned" rpm )

oh and its not so much over lap that causes this as it is just the fast flowing air bouncing back ( to use rather simple name ) off the vlave one it is closed ( investigate pulse jets for more understanding )

The harmonics involved are much more complicated than a simple open ended resonator. ( see local university for more of an understanding ).