Backfiring

[liami]

Just did my 600 mile service including the oil with filter change, throttle bike sync, checking main mount bolts with tires and engine and stuff, and checking my chain tension. Put it all back together and now I'm having slight backfiring upon letting off the throttle. Everything on my bike is still completely stock, including the muffler. Suggestions?

[wickedtwister]

Did you do service or dealer? How did you do throttle body sync.

[liami]

I did all service. Took off all fairings over tank, took off tank, took off vacuum hose from left TB and took off the cap from right TB. Put tank back on and synced TBs, only adjusting right side screw. Then I put everything back together the way it was before, including the hose, but I did drop the cap for the right side to where I can't find it under the starter. Ordered a new one there

[Jeckler]

...but I did drop the cap for the right side to where I can't find it under the starter. Ordered a new one there

You have a massive leak. Any local auto parts store will have vacuum caps. Stop riding it until you replace it.

[eraser8]

I did all service. Took off all fairings over tank, took off tank, took off vacuum hose from left TB and took off the cap from right TB. Put tank back on and synced TBs, only adjusting right side screw. Then I put everything back together the way it was before, including the hose, but I did drop the cap for the right side to where I can't find it under the starter. Ordered a new one there

haha!! It happen exactly the same thing for me.... But I was able to recover it (with a lot of chances). I will give you my tip. 
I took my blower gun on my compressor and blow it any direction from the left side of the bike. At some point, I saw the little cap making some up and down. And with a chance, the cap ended by getting out of there.
 
Good luck!
 

[wickedtwister]

I did all service. Took off all fairings over tank, took off tank, took off vacuum hose from left TB and took off the cap from right TB. Put tank back on and synced TBs, only adjusting right side screw. Then I put everything back together the way it was before, including the hose, but I did drop the cap for the right side to where I can't find it under the starter. Ordered a new one there

Saying you dropped the cap in the OP would have been helpful. Replace the cap and you're good to go.

[liami]

Damn that sucks cuz it's my only mode of transport...

[liami]

What's the danger of driving it without the cap, besides the backfires?

[Jeckler]

It's sucking air, running wicked lean.
 
You don't have an auto parts store nearby?

[liami]

I do, I just didn't wanna spend extra. I know it's not much but yea

[bmwpowere36m3]

$5 for some vacuum caps... come on man. The more time I spend on this forum, I'm starting to believe "typical FZ-07 owner = total cheap ass"

[Guest Ralph]

Cut a short piece of the vac pipe from the vac gauges block one end with something
that will not get sucked through or fall out and use that till you can get a new un.

[yotaman02]

I did all service. Took off all fairings over tank, took off tank, took off vacuum hose from left TB and took off the cap from right TB. Put tank back on and synced TBs, only adjusting right side screw. Then I put everything back together the way it was before, including the hose, but I did drop the cap for the right side to where I can't find it under the starter. Ordered a new one there

haha!! It happen exactly the same thing for me.... But I was able to recover it (with a lot of chances). I will give you my tip. 
I took my blower gun on my compressor and blow it any direction from the left side of the bike. At some point, I saw the little cap making some up and down. And with a chance, the cap ended by getting out of there.
 
Good luck!

I did the same thing. kind of a p.i.t.a but you can get it out.  

[liami]

Bought the caps and put one on. I guess it's not necessarily that I didn't want to spend the extra money, I had just already ordered replacement cap and didn't want to buy extra if I didn't need to. Now I'll have two just sitting around, hopefully I don't lose them. I didn't realize it was making my bike lose power too, but when I test rode it, along with getting rid of the backfiring, I also wheelied really damn high and scared the crap outta myself.

[wickedtwister]

Thought you couldn't get it up? A word to (or from) the wise. If this is your only mode of transportation stop trying to do wheelies eventually you will drop it. Also if you plan on working on the bike I would invest in a shop manual the dealership ordered one for me with the bike. If you don't know exctally what you are doing don't try. Find a shop to take it too.

[rick]

 Now I'll have two just sitting around, 

not to worry, you'll need one of the spares the next time you do a service. lol 
Almost hate to ask, but would you leave spark plug out if you dropped one and it broke? 
 
Sorry - but you do see my point. Next time find or replace lost bits before you ride. Not a lot of places for stuff to hide on this bike - imagine having a full fairing. 
 
BTW, even with the wheelies, i'll bet the OE plug is still where it fell to. 

[liami]

It made itself get up today somehow. I don't really know what changed, maybe when I adjusted my throttle bodies it made it better, but then dropping the cap made it weak still? Possibility. So fixing it all made it possible for the wheelies. And that's true, I really shouldn't do the wheelies on this...guess it's a "my penis is bigger" thing for guys around here lol.

[wickedtwister]

It made itself get up today somehow. I don't really know what changed, maybe when I adjusted my throttle bodies it made it better, but then dropping the cap made it weak still? Possibility. So fixing it all made it possible for the wheelies. And that's true, I really shouldn't do the wheelies on this...guess it's a "my penis is bigger" thing for guys around here lol.

if you left off a vacuum cap off its sucking air so its getting more air than normal but its not getting anymore fuel.  Yes this bike has an O2 sensor but its only activated when the Econ light is on, on the display.   So its running lean and making a bit less power.  Unless you've had a flash done on the bike its already lean in the mid range.  The throttle body sync only really going to help on idle and just slightly off idle.  
You may be trying to prove something by the wheelies but I can guarantee that my girlfriend can do a bigger wheelie on her "girl bike"  (without using the clutch).  Its a Z1000 with flowers embroidered on the seat and stuffed animals ziptied on the controls.  I get hell when I ride it into work until I ask the guys what kind of bike does your wife/girlfriend/ect ride? 
 
Its probably easier to just whip it out and measure it.  My point is it doesn't matter how good of a rider you are or how much money you dump into your bike someone will be able to do wheelies or whatever better.
 
 
 

[liami]

I know all this, thank you. Wheelies are fun to do and when driving by on the beach, the girls around my area seem to love it. Attention is nice at select times and when I want that attention, here comes a wheelie. They also simply give me my rush of adrenaline. One other thing, I show my stepdad the wheelies and he's in awe cuz he has a busa and he too much of a pu**y so actually do anything like that so it's funny to watch his reactions. I get that they're unsafe and maybe I shouldn't be doing them on my only mode of transportation. Thank you to the few who show concern about safety and what not. But same thing I tell to other people who ridicule people about driving unsafely...unless you're a cop giving them a ticket right there and then, people don't normally just change driving behavior because "maybe you should/shouldn't..." If I keep doing wheelies, I face consequences. If I don't, I'm safer. And either one is fine, it's my choice to be stupid or safe. Everyone changes those choices now and then. It's not like I drive around popping wheelies on every street I possibly can. Don't like wheelies, don't do them...thanks for concern but I'll learn one way or another.

[avanti]

Sheesh, just plug it with something it cannot suck in!!! And, then "SPLURG" on the caps!!!