FZRSupport: the FZROnline Archive

Okay, im back yet again with another heaping problem. So, cylinder 4's boot was bad so i replaced the whole unit for cylinder 1 and 4. All get spark and seem to fire well with no skipping. But, she lost a ton of power. Sounds like a dirt bike now. When i give her gas she sputters and goes up and down with power. All this started while driving on the freeway and felt like i lost a cylinder for power. The spark plug boot was bad and only firing off 1,2, and 3 for a while. I got 4 to fire and 100 miles later this happened. Swapped out the unit for 1 and 4, now i have a loss of power and a dirt bike sounding FZR. Help!

Very tough to diagnose over the interweb. Did you hook up the wires to the correct spark plugs? Double and triple check.

fouled a plug.

Change them (all). Autolite 4303 are cheap, good, and widely available.

All brand new plugs and wires, triple checked the order. She wants to run but struggles, cant go uphil at all, exhaust smells rich. So lost?!

brand new plugs, when? when you changed the coil pack and wires?

May have been enough unburnt fuel in the cylinders to immediately foul one or some of them.
Are all four exhaust pipes hot? The cold ones are where your problem lies.

I still have to check the pipes for cold or hot. I have to go out of town for a few days so ill do it when i came back if i cant do it on my way he tonight. When should i try the pipes? Fresh start or after i drive it all the way home? Spray bottle to see how long it takes to dry off the pipes, or??? I dont have a digital temp sensor or anything like it. Thanks!

And, yes i chandes the plugs when i swapped the coils. Used NKGR plugs.

Okay, so strangest thing happened. I left work today at 2 in the morning, about 45 degrees outside and ahe ran like a champ all the way home. Would the temperature impact the bike that much? Could that be a sign to air fuel ratio? I wont have time to ride her again until thursday or friday. So confused, but a little flad that the power was back for a short time today. Any ideas? Thanks

Yes, a rich mixture will be compensated for at lower air temps (denser air).

The issue/problem would be "why did it just start happening while going down the road?"

This bike has been a work in progress, previous owner was a butcher! Ive had to replace the coils, clean and synk carbs, remove epa caps for the adjustment screws and put them back in there correct location, numberous electrical fixes and more. Im just trying to get her rideable constantly. If im too rich should i turn the adjustment screws in or out to correct, and how far? Im at 3 turns out right now, should i go to 2 1/2 and see?

Turn the screws in to lean the mixture.

Looks like only cylinder 4 is rich, plug is wet. All the others look normal, can i adjust only cylinder 4's idle adjustment screw or do all 4 have to be set the same?

Okay, im tired of these intermitent flaws! I turned the bike on today and went for a short ride. 75 degrees out, and ran like nothing was wrong. Im so lost! Should i still adjust the screws?

I had to go back and read all the posts, well to me it sounds like a spark problem. You are not burning fuel on one or more of cylinders. I am thinking this because you said you just changed everything. I would double check all my connections, test for good spark. If everything checks out, now I would sync carbs, check float height, clean them out, and adjust the pilot screws.Its ok if they are not set exactly the same. But they need to be close.

Reelrazor is saying , start the bike, let it idle, spray the pipes with water to see if any pipes are cooler than the others. He is trying to say we need to see if, one pipe is cooler, which cylinder is misfiring.

Try removing the #4 cap from the plug wire, trim the wire back a 1/4", replace the cap.