Gen I Flooding

Team Yamaha Fz1

Well-Known Member
Hello.

I am new to the site and a new rider as well.

I have a 2002 Fz1 I’m not sure of the mileage due to the cluster being worn out ( another day ) . I recently got a jet kit added, carbs synched new clutch, new chain and sprockets (15t-45t) new fuel pump, new fuel lines. Oil change, Radiator Flush, spark plugs, carb boots.

For the past few days I’ve noticed heavy gas smell and when I’m riding the power band doesn’t hit until I find the sweet spot on the throttle. I turned the Petcock slightly off and it was riding better in terms of the power band hitting but at wop it was hesitant. I’m not sure what I should do. I’ve checked everything I could think of.

Any help would be greatly appreciated
 
Klurejr Thanks for the reply.

No the choke is closed all the way and I don’t see any fuel leaking.

I have the valve half way between closed and open just so I can get a power band if not it won’t take off like it’s supposed to.

Im at a loss
 
One of the critical adjustments when installing a jet kit is the carb float height adjustments. It sounds like the floats may be set too high. What jet kit was installed, and did yo do it yourself, or have a shop do the work?
 
I tried to get Ivan’s but he said it was a long wait because he was backed up so it’s just a dyno and no I had a mechanic from a shop do it along with everything else.
It was working fine it just started to do it. And as I stated I have the fuel valve half open and it is riding very good but I’m definitely sure that’s not how it’s supposed to be. The gas smell is bad I have to keep my garage open a third
 
You shouldn't need to throttle the fuel at the petcock.

Have you pulled the plugs to see if they are wet, or if one or two of them smell like gas? That could help narrow down the specific carbs that may be the culprit.

I am assuming that if it ran well for some time after the jet kit was installed, then perhaps it's not the float settings. If it started really soon, maybe it is. Did he install a carb kit (o-rings, gaskets, etc? If not, it may be something as simple as the float bowl o-rings or maybe even one (or more) of the float valves that need replaced. Those would be the small valves that shut off the fuel to the fuel bowls. Then again, it could be that the float seats just need a cleaning. Maybe something got introduced during the jet kit install that has worked its way into the float seat. If the valve can't shut the flow off to the carb, it will overflow into the carb, and you get flooding. I would bet that is where the issue likely is.
 
You shouldn't need to throttle the fuel at the petcock.

Have you pulled the plugs to see if they are wet, or if one or two of them smell like gas? That could help narrow down the specific carbs that may be the culprit.

I am assuming that if it ran well for some time after the jet kit was installed, then perhaps it's not the float settings. If it started really soon, maybe it is. Did he install a carb kit (o-rings, gaskets, etc? If not, it may be something as simple as the float bowl o-rings or maybe even one (or more) of the float valves that need replaced. Those would be the small valves that shut off the fuel to the fuel bowls. Then again, it could be that the float seats just need a cleaning. Maybe something got introduced during the jet kit install that has worked its way into the float seat. If the valve can't shut the flow off to the carb, it will overflow into the carb, and you get flooding. I would bet that is where the issue likely is.

That makes sense but I was there with him when he installed everything and all the gaskets and everything were installed. Yes when I have the valve open all the way it’s flooding while I’m riding.
I’m at work I walked outside the warehouse just to see something and halfway to the bike I can smell gas in the parking lot.
So your saying just take out the spark plugs to see which carb is the one?

wouldn’t that cause power loss? Again I’m just asking.
 
I mean I did get the job done for $550 total everything but he did install my clutch without the new springs I had to do it myself. He also did some other corner cutting ways that had me stranded on the side of the road. Glad I had tools under my seat.

so you might be right he probably I want to say mistakenly did something or the carbs are just messing up.

could a bad gas tank cause that also?
I am in the process of getting gas tank sealer and replacing the float ball and petcock and gas cap.
 
That makes sense but I was there with him when he installed everything and all the gaskets and everything were installed. Yes when I have the valve open all the way it’s flooding while I’m riding.
I’m at work I walked outside the warehouse just to see something and halfway to the bike I can smell gas in the parking lot.
So your saying just take out the spark plugs to see which carb is the one?

wouldn’t that cause power loss? Again I’m just asking.
Removing the plugs will allow you to read the plug to identify which cylinder(s) are the issue to identify where to look for the problem, then reinstall the plugs.
 
I mean I did get the job done for $550 total everything but he did install my clutch without the new springs I had to do it myself. He also did some other corner cutting ways that had me stranded on the side of the road. Glad I had tools under my seat.

so you might be right he probably I want to say mistakenly did something or the carbs are just messing up.

could a bad gas tank cause that also?
I am in the process of getting gas tank sealer and replacing the float ball and petcock and gas cap.
I would think that if you aren't seeing any leakage from the tank to the carbs, that probably not the issue. Fuel does seem to be getting to the carbs if I understand it right.
If the carb float valves aren't sealing well, extra fuel can overfill the carbs and potentially cause a flooding situation. If the overfill to the point of draining to the overflow line, that could cause the gas smell as well.
Leakage through the float valve could be a bad float valve o-ring, dirty float valve, damaged float valve or seat, or an issue with the float heights.
For an Ivan kit, the float height is 14 to 14.5mm. I had a holeshot kit on mine, and I set the floats at 13.5mm. That worked well.
 
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I would think that if you arent seeing any leakagefrom the tank to the carbs, that probably not the issue. Furl does seem to be getting to the carbs if I understand it right.
If the carb float valves aren't sealing well, extra fuel can overfill the carbs and potentially cause a flooding situation. If the overfill to the point of draining to the overflow line, that could cause the gas smell as well.
Leakage through the float valve could be a bad float valve o-ring, dirty float valve, damaged float valve or seat, or sn issue with the float heights.
For an Ivan kit, the float height is 14 to 14.5mm. I had a holeshot kit on mine, and I set the floats at 13.5mm. That worked well.

Do you think since I didn’t install the Ivan’s it’s not gonna be riding 100%. I mean from when I bought it for $1,200 to now I am very very pleased just the gas smell. Ok I fuel I’ll have to figure it out starting with the plugs first
 
I did a holeshot kit. No drilling. Worked great. I think you said it was a dyno kit. I'm not familiar with those, but any kit not done right is a problem.
I still suspect it's related to the floats, float valves or o-rings.
I'm not the world's expert on carbs, but I've done several jet kits.
Maybe somebody else here can chime in.
 
I did a holeshot kit. No drilling. Worked great. I think you said it was a dyno kit. I'm not familiar with those, but any kit not done right is a problem.
I still suspect it's related to the floats, float valves or o-rings.
I'm not the world's expert on carbs, but I've done several jet kits.
Maybe somebody else here can chime in.

I’m afraid to touch the carbs and not be able to get them back right. I can do easy things but when I comes to 14.2 - 13.2 and set it there I get anxiety lol..

I guess I’ll have to find another motorcycle mechanic that’s mobile here in Orlando

I appreciate your help Blue Flash
 
Update:

I pulled each plug and nothing there. I haven’t taken off the carbs because I don’t wanna mess it up.

It’s my gas cap! Gasket must be shot because I have been trying to wheelie try being the KEY Word here but when I did gas spilled all over the tank from the gas cap. So after I parked it I went over and smelled a few inches above the cap and it hit me like a bag of bricks.

*** Now my question is would that make the bike run differently since air is getting in??*****


I am trying to order a newer one but I am having problems finding it.

Any help will be greatly appreciated LOOKING FOR A YAMAHA BLUE ONE!
 
I am trying to order a newer one but I am having problems finding it.

Any help will be greatly appreciated LOOKING FOR A YAMAHA BLUE ONE!

I do not see why a leaky gas cap would cause the carbs to flood. But since it is leaking that is a good spot to start. Can you not just get a replacement seal for the cap on the tank? A new tank is gonna be expensive, even the dented ones on eBay are expensive, plus the tank will need YOUR cap moved to it since it is keyed to your bike key.
 
I do not see why a leaky gas cap would cause the carbs to flood. But since it is leaking that is a good spot to start. Can you not just get a replacement seal for the cap on the tank? A new tank is gonna be expensive, even the dented ones on eBay are expensive, plus the tank will need YOUR cap moved to it since it is keyed to your bike key.

Subconsciously I thought the same way about the gas cap causing it to flood but isn’t it gravity pulled so if air is getting in wouldn’t that cause more gas to be dumped in? It might just be wishful thinking

My tank is fine it’s just the gas cap. After further inspection the key lock part is also a little lifted up. So I am just trying to replace the whole gas cap with the gasket.
 
Update:

It has been running fine I even turned the fuel valve open all the way, today I filled up to the top and it runs sluggish not BAD but I feel the hesitation in 2nd gear.

Any ideas?

P.S - I still have plenty of power to where I am still able to power wheelie in 2nd though...
 
And if you do not fill it to the top the sluggishness goes away? Is the cap still leaking?


No it doesn't. its just not as noticeable I can go 140 before it starts to stutter where when it's full I can only hit 85-90 and it sluggish.

I ordered it from Yamaha waiting for it to come in.
 
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