FZRSupport: the FZROnline Archive

So, i bought the bike and the exup valve was gone, could that cause any lean/rich issues? Should i have the carbs tuned again or is it okay with the free flow exhaust?

Thanks!!!

It could cause a lean condition, your moving air through the engine better without increasing amount of gas. Any reason why you think the previous owner did not change the jetting? Any problems? Most use 110 mains with free flowing exaust. You could open the carbs and check to see what's in there.

Also if you or no one else has pulled the little caps off the pilot adjustment screws you should do that. They like to move around on you.

It's not really a huge deal on the 600. Most of them don't have the EXUP, just the CALI versions do. You have a lot of other emiisions crap on there that can be removed too...

darrin

"Tuning" is a relative term. If all the other stuff has been removed (the valving surrounding the oil filter) and the the ports on the motor have been plugged, then you should be able to rejet (stage 1 or above) and be fine.

The missing EXUP shouldn't much affect the main jets, as it is fully open by the time you've got the throttles WFO at redline. What may very well be affected is your mid-range and bottem end jetting.

sweekster wrote:"Tuning" is a relative term. If all the other stuff has been removed (the valving surrounding the oil filter) and the the ports on the motor have been plugged, then you should be able to rejet (stage 1 or above) and be fine.

No idea aboit the valvinv surpumding the oil filter or ports on the motor. Any wY to "show" me. Links to pics or posts where people have done this? Ant the pilot screws have to be adjusted to not run as rich right? Im at 3 turns out right now, shoild i tey 2 1/2 turns?

Thanks

My pilot jets are set about almost 3 turns out, but it really depends what your bike likes best. I don't know too much about exup stuff. Someone else will have to answer.

http://images.powersportsnetwork.com/fi ... cooler.gif <-click there.


The air cooler, the servo controlled valve in the stock header, and the servo control box (don't recall it's exact name at the moment) are what make the motor exup. I read somewhere that the intake cam is also different in them but have no concrete proof of that. I ran my old 600 with just the servo and valve in the header and removed the air cooler. If you have that surrounding your oil filter OR it's been removed and the ports next the exhaust have been plugged then you have an EXUP motor. If you do not have that stuff and there are no plugged holes in your motor then you don't have an exup motor in your bike. Could have very been swapped for another motor some time in it's life. Which I'm guessing is the case with your bike or it's a simply you actually have a non cali bike. Also, the "pilot screws", as you call them, are actually the idle mixture screws and the adjustments made really affect idle more than they do at higher points in the rpm range. The jetting I was referring to happens in inside the carbs.

Okay, so if i adjust the idle mixture screws it will lean out the mixture when turning to the right? Will that help solve the rich issue. Only cylinder 4's plug looks wet, can i adjust one of them and not all 4 or should they all be set the same. And with onlymone looking bad i think that wiuld sugest another problem within the carb right? Maby float height?

I sprayed the pipes today after a good hour ride, she ran well but struggled a bit in high rpm's. cylinder 1,2 dried almost instantly, 3 took just a little longer, and 4 took a while longer. Cylinder 4 was not firing before, i removed the exup housing and could see gas in the pipe off #4. Changed the plugs and coils and 4 started to fire, got power back. Checked the exhaust again and all 4 pipes are dry and seem to be firing. I have checked all 4 coil wires for spark and they all fire, plugs are 3 weeks old, any ideas from here? Want this resolved so bad, just want to ride her without having to worry about anything. Thanks guys for all the help so far and in advance for the replys!