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Yoshimura Full Exhaust Fumes - Scudrunr_imp - 03-16-2015

Folks,

I installed a full Yoshimura system on my bike just as soon as I bought it. I love the exhaust. It sounds great, it looks good, it’s very light, easy to install, and it definitely helps in the power department.

I have it running with the O2 sensor installed.

My dilemma is that the exhaust is quite fumey. I miss the cat. My wife is sucking fumes the entire time she rides with me. I use the bike to commute to work so I don’t want to show up smelling like the track.

Would a tune help? Flash or PCV? I was under the impression most bikes run lean from the factory and a tune would enrichen the mixture. In my mind a richer mixture would make the problem worse. Do I need to eliminate the O2 sensor? Some sort of wind deflection?

Thank for the help guys!


RE: Yoshimura Full Exhaust Fumes - avsbezzy_imp - 03-16-2015

have your ecu flashed at Guhl motors for fuel optimization.
Your bike will run better, cooler, past 110 miles per hour if you want, past 8500 rpm also. get in touch with them for details.
I had my ecu flashed, pair valve mod, Over racing slip ons (dual). bike runs great and cooler, no popping on decel, and a exhaust melody that turns HD riders head!!!!


RE: Yoshimura Full Exhaust Fumes - HikerToo_imp - 03-16-2015

the pair valve mod would get rid of the decel popping, although most people report more fume smells after that mod.
I had it for a while, although after my ECU flash, went back to normal pair valve hose not being plugged.
I'm not sure or convinced an ECU flash or PCV will get rid of fumes....could be the absence of the Cat?


RE: Yoshimura Full Exhaust Fumes - CIP57_imp - 03-16-2015

(03-16-2015, 12:27 PM)Scudrunr_imp Wrote: Folks,

I installed a full Yoshimura system on my bike just as soon as I bought it. I love the exhaust. It sounds great, it looks good, it’s very light, easy to install, and it definitely helps in the power department.

I have it running with the O2 sensor installed.

My dilemma is that the exhaust is quite fumey. I miss the cat. My wife is sucking fumes the entire time she rides with me. I use the bike to commute to work so I don’t want to show up smelling like the track.

Would a tune help? Flash or PCV? I was under the impression most bikes run lean from the factory and a tune would enrichen the mixture. In my mind a richer mixture would make the problem worse. Do I need to eliminate the O2 sensor? Some sort of wind deflection?

Thank for the help guys!

I have the same exhaust with a flash and map. You are correct, not so much the flash but putting a map to correct the lean condition of the bike will increase the fumes. My bike runs at a perfect 13.2 A/F ratio throughout the range. If you do the pair mod to eliminate farting on decel you will get a stronger odor of unspent fuel. Its not a problem for me as a solo rider, i don't smell anything.

When i warm the bike up it smells like a dual exhaust high performance car of the late 60's, i sat behind many of them while working in a gas station in the early 70's.

As far is the O2 sensor i have mine hooked up, I'm sure the ECU reads off the sensor. Someone here with more knowledge will chime in soon regarding weather that would make a difference or not. I don't believe disconnecting the O2 will do anything to reduce or eliminate the unspent gas.


RE: Yoshimura Full Exhaust Fumes - ClassicVW_imp - 03-17-2015

Well... not trying to sound harsh, but really, what did you think was going to happen when you remove a device that removes air pollution? It is said that a vehicle's exhaust flow without a catalytic converter is 25% carbon monoxide. A catalytic converter converts up to 99% of that carbon monoxide (CO) in the exhaust to carbon dioxide (CO2). What your wife is smelling is carbon monoxide, which is not a good thing. You also need to consider never warming up or idling your bike either inside a garage or outside a garage with the exhaust facing into the garage. CO2 is not a safe gas to inhale, but CO is much worse both in the short term and long term. Obviously, it's what gets the job done when someone commits suicide by CO poisoning.


RE: Yoshimura Full Exhaust Fumes - ChipBeck_imp - 03-17-2015

(03-17-2015, 12:14 AM)ClassicVW_imp Wrote: Well... not trying to sound harsh, but really, what did you think was going to happen when you remove a device that removes air pollution? It is said that a vehicle's exhaust flow without a catalytic converter is 25% carbon monoxide. A catalytic converter converts up to 99% of that carbon monoxide (CO) in the exhaust to carbon dioxide (CO2). What your wife is smelling is carbon monoxide, which is not a good thing. You also need to consider never warming up or idling your bike either inside a garage or outside a garage with the exhaust facing into the garage. CO2 is not a safe gas to inhale, but CO is much worse both in the short term and long term. Obviously, it's what gets the job done when someone commits suicide by CO poisoning.

Classic,

Carbon Dioxide is very safe to inhale even in fairly large concentrations. Even at 20+ times it's atmospheric level you wouldn't even notice it. At 200+ times normal levels it is replacing enough oxygen in the air to start making breathing difficult but the co2 itself isn't toxic. Our own lungs produce it and we exhale co2 with every breath. People who work in enclosed agricultural greenhouses/hot houses that pipe in co2 to raise the level to 5 times what it is in the atmosphere have no problems. CO is another story and when it's present the lungs soak it up like a sponge. Even cars with functioning cats produce enough CO to be fatal in an enclosed garage.

Both co2 and CO are odorless gasses. She is certainly smelling exhaust gassed but she's not smelling CO.

Chip


RE: Yoshimura Full Exhaust Fumes - ClassicVW_imp - 03-17-2015

Yeah, I know better. What I should have said was she is smelling exhaust gases which also contain CO.


RE: Yoshimura Full Exhaust Fumes - Scudrunr_imp - 03-17-2015

Classic,

I get your point. I know that it is ultimately cat related. This is the first aftermarket exhaust I've had on one of my bikes. Unintended consequences I guess! Are there any full systems that retain a cat?


RE: Yoshimura Full Exhaust Fumes - Motogeezer1949_imp - 03-18-2015

We have the ceramic coated full system and other than what I would guess was the initial curing of the coating, haven't noticed any odor or fumes. The right side O2 sensor is screwed into the collector and the left side has the sensor eliminator plugged into it.