My 7 is running rough. Any Ideas?

[dutchy]

Got on my girl yesterday and it didn't feel as good as normal. After that i went to get on the bike (1998 zx7r for those who don't know) to ride to work and noticed immediately that it wasn't sounding healthy, thought it may have just been a cold morning 'thing' but before i even got a few houses up the road i knew it wasn't going well at all. I'm no trained mechanic but here are my thoughts/theorys.

Instead of it's normal running tone it seems to have a gargle. Its repeatative and rhythmic and increases with the revs, and occasionally backfiring which makes me think for some reason only one cylinder is effected. I'm going to begin with a simple attack with carby cleaner but i'm not sure thats the issue seeing as though its backfiring that'd mean fuel isn't having trouble getting in there, right??? its just having trouble with the firing.

Bikes done 41000 k's ish and i'm unsure about when, if at all, spark plugs have been replaced so i might be doing that just because it probably should be done anyway. Also while its up on the stand i'll be doing other servicing. (oil and filter change, collant so on).

Any ideas people??? I'll appreciate all help.

[robracer]

Corey that could be anything from a fowled plug to a coil or possibly dirty carby
Mate start with the plugs

[Stace]

drain the carbs as well and check the bowls for crap

[Tinman]

I would check spark

[zx6rider]

Same as everyone else, I would Start with plugs, then leads, coil, and if all else fails....
































BUY A SUZUKI!!!

[tim]

Same as everyone else, I would Start with plugs, then leads, coil, and if all else fails....

BUY A SUZUKI!!!

+1

[dutchy]

Removed the airfilter today on my way to get to the sparkpugs. I will be taking the oppertunity to remove all the bug guts from the airbox while its off (see pic), also clean out the filter while i'm there. Shame i don't have the money this week to put in a k&n replacement.

Took the carbies off to have a look, i like to pull things apart and i understand them better if i do so. I took two of the four apart to look in the float/bowl and they were spotless (with a quick examination). when i went to go to the third i had a rather stuburn screw become unwilling to play. instead of trying to check it (and stuff the screw) i figured that i'd leave it be and just go on with the general idea that if the other two were spotless then the remaining two were probably not going to that bad.

on to the sparks. i'm getting newbies tomorrow morning. i'm pretty sure that'll be most of my problem solved. two of them were actually begining to corrode away, not good!!
If the corroding and carbon deposit wasn't enough reason to replace them, then probably dropping one while taking it out is!!
Yeah, that deffinately tipped the scales right there!!!

[dutchy]

New spark plugs in! Bike fine!

Actually its better than it has been in a while. was running a bit rough every now and then and i was also starting to get a bit of vibration up through the tank. All gone now.

Now i'm off to "to out of it to post"!! Its been a big day, celebrating, i've got a big life change ahead....but thats a differant thread!!!!

[zx6rider]

Good Stuff Corey, now after reading the first post I noticed I didnt quite read it right the first time...

Got on my girl yesterday and it didn't feel as good as normal. After that i went to get on the bike (1998 zx7r for those who don't know) to ride to work and...

So we are all still wondering why "it didnt feel as good as normal"?