I smell gas. By Guitarman (Read 1,713 times)

[Guitarman]

Not every time, but often enough, I smell gas when I walk up to my bike. I've looked everywhere but I can't find any leaks. Help please.

[Bashan]

Nov 5, 2013 22:09:10 GMT -6 Guitarman said:

I smell gas when I walk up to my bike.

That's odd, my wife says that when she walks up to me. OH! I see, gas-oline. That's different. Do you have a vapor recovery system? If you have a vent hose off of the gas tank that runs to a check valve and then a canister you have a VRS or very redolent smells, aka vapor recovery system:

The Chinese scooter industry has spent millions of dollars and countless man hours devising this system on scooters to reduce.....oh PWAH HAH HAH!!! The Chinese vapor recovery systems smell like I do after Mexican food and recover upwards of two molecules of gas vapors.

If your bike has been on it's side, or you overfilled your gas tank a little, or you've ridden your scooter, or you bought a Chinese scooter, then you probably have issues with your VRS, or vehicular raunchy smells. Hey, that wasn't me, it was the dog, really....it was. She never believes me, mainly because we don't have a dog. The gas smell comes from the fresh air tube if the canister is saturated with gas which is all of the time.

Now, some people on other forums have actually suggested that you can remove your VRS (virtual reeking scooter)!! I find the very thought of running counter to the EPA reprehensible and here is how you can remove the system:

Before

After

I only post the diagrams so that if you see anybody post something close to that you can turn them into the EPA! Well, that is if they're from another forum.

[FrankenMech]

Usually there is a problem with that vacuum line or the valve it controls. It may or may not be a 'real' vacuum line. Lines from the carb intake are semi-vacuum lines. Lines from the intake manifold are real vacuum lines. I like to recover all the gas vapor off the tank but why do they make it so complicated? On regular size cars and trucks with a bad purge system I have often used a 'controlled leak' through a real vacuum line from the manifold to 'purge' the charcoal canister. The 'control' I use is usually a 1/16 (0.62)" or 1.5mm orifice made with a drill through some brass or aluminum round stock inserted inside the vacuum line. That would be too large for one of these micro engines. I don't have a clue yet about what size purge orifice to use on a 50cc thumper. I used a 1/8" orifice on the semi-vacuum line to vent my valve cover. My China scoot does not have any vapor recovery system other than the vent to atmosphere in the 'After' diagram which is stock. They didn't even have a hose on the vent tube. I had no charcoal canister from the factory.

[Bashan]

VERY good catch Frankenmech, you are exactly correct and my bad. The vacuum valve on the vapor canister is actuated by the vacuum on the intake manifold, not south of the airbox. I had it wrong on the diagrams on this thread which I have now amended to be accurate. Thanks for the correction and you're banned.

[FrankenMech]

Nov 6, 2013 3:21:26 GMT -6 Bashan said:

VERY good catch Frankenmech, you are exactly correct and my bad. The vacuum valve on the vapor canister is actuated by the vacuum on the intake manifold, not south of the airbox. I had it wrong on the diagrams on this thread which I have now amended to be accurate. Thanks for the correction and you're banned.

Hehe, I didn't say anything was wrong...

I did a lot of automotive work back in the late 60's and early 70's when a lot of this emissions stuff was pioneered. I go back to road draft tubes before the PCV valve, points, oil bath air cleaners, REAL horsepower back in 67-70 (I was driving around with 500HP on tap and 8mpg with gas at 25-30 cents), on to the vacuum snake-pits of 71-74's, retarded camshafts and timing, smog pumps, unleaded gas, and catalytic converters in 75. Cats were a good thing. I got out about the time computers took over. I have witnessed exactly how important vacuum and electrical systems with their connections are to reliability and longevity. Unfortunately if my China scoot is in any way representative then scoots suck.

[LUKE]

Carburetor------> obsolete (thing of the past)


go ECI....go green!!!

[FrankenMech]

But, but, but, -I AM a thing of the past...

I was good with carbs when I didn't shake and still had a brain. I understood them. I have tools and parts. I understand the engine management systems also, but I don't have the tools and a junk box full of parts to work on them.

[LUKE]

the thing about carbs is that one day it runs good, another day it runs stupid, and it goes to both chinese and japanese.,,if you ran over a big pothole in the road the carb tunning gets upset and starts to run insane again...i hate it...

[FrankenMech]

Nov 7, 2013 12:44:17 GMT -6 LUKE said:

the thing about carbs is that one day it runs good, another day it runs stupid, and it goes to both chinese and japanese.,,if you ran over a big pothole in the road the carb tunning gets upset and starts to run insane again...i hate it...

The same thing happens with electronic systems. Run over a pothole and a wire connection comes loose, a wire shorts, a wire breaks, the connection is made again, etc -It also happens way too often.

Gremlins!

[LUKE]

huh? wire connection?? let me ask you, how many wire connections there is in a scooter??? and how many carburetors are there in a scooter?,,,haha, it means that everytime i ran over a pothole there is always one wire connection(coupler) that will get dislodged because there are maybe 20 of them around the scooter...lol?? amazing and unbelievable frank.
you disappoint me to the maximum level..


you need to give us a better explanation franky..lol

[redroush00]

There arent 20 wires that will effect how the scooter runs. A good bump one in awhile helps keep the float happy lol

[redroush00]

Someone playing with the throttle maybe? that will dump some unburned fuel. I did that to a harley i saw parked once just to see how the throttle felt. Next thing i saw was some gas dripping on the ground...I was outa there before mr burley could yell WT* !

[LUKE]

Nov 7, 2013 14:07:38 GMT -6 @redroush00 said:

Someone playing with the throttle maybe? that will dump some unburned fuel. I did that to a harley i saw parked once just to see how the throttle felt. Next thing i saw was some gas dripping on the ground...I was outa there before mr burley could yell WT* !

this never happens in the ECI equipped scooter..never!!!

[FrankenMech]

Luke, personal attacks are not necessary.

The 'wire' problems extend beyond scoots to most vehicles today. The major OEM's know the wire problems and they are working on it.

I was just trying to explain that vehicular problems are not confined to antiquated carbs. I enjoy the EFI on my Ford Ranger. Twist the key and it starts is nice. No pumping gas pedals or setting the choke etc etc that has to be done with carbs. I grew up with carbs and I am comfortable with them. Most people prefer EFI and so do I. I have an Edelbrock 600cfm on my 78 project truck to play with. I still have a carb on the scoot which does not bother me. Once I had to get into it I discovered it is similar to a variable venturi design that I am familiar with from many years ago. I am not edumacated about scoots and motorcycles yet but I am learning. Getting a China scoot running has been an education.

I also agree with you about the Japanese scoots being superior in almost all ways, fit, finish, workmanship, documentation, quality and QC, etc -except for price. I could not afford a Japanese scoot or a European scoot so I ended up with a China scoot and a whole bunch of sweat equity. I expected some, but not quite as much as I got, but I am used to that because Murphy loves me.

[LUKE]

Murphy loves you?? you mean you own a Morphous too??...but no biggie Frank, sorry if it looks to you as if it was a personal attack, sorry.
please join me in my Quest,,,. a Quest to convince newbies to that hey there are other better quality scooter than chinese scooters,,don't get fooled and enchanted with beautiful shiny colors..it's the durability of the components that counts..