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I have a relatively new bike, bought it few weeks ago, did the 600 maintenance, currently at around 1600 miles when I noticed there are three tubes coming out from under the fairing, by the kickstand, and behind the engine. Anyone else ever had this? Is it a problem? Any help/advice is MUCH appreciated
 

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They are fuel system vent hoses, which are supposed to be there... nothing to worry about.
 

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They are fuel system vent hoses, which are supposed to be there... nothing to worry about.
I filled it to the rim with fuel the other day. Since then the gauge has gone down a bar and I've ridden about 50 miles since the re-fueling. My driveway has a pretty decent incline and don't usually park it there in direct 95 degree Florida sunlight but i did today. I was taking some new pictures lol.
So I just went to bring it in and there was a 3 inch wet area, wouldn't call it a puddle just wet. It is coming out of 1 of the 3 tubes there, and when I stick my finger in the tube it feels pretty oily but has a very faint smell of gas. What are these 3 tubes for? I know what the engine breather pink tube is, and know there is a fuel overflow tube but this was pretty oily between my fingers.
 

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I filled it to the rim with fuel the other day. Since then the gauge has gone down a bar and I've ridden about 50 miles since the re-fueling. My driveway has a pretty decent incline and don't usually park it there in direct 95 degree Florida sunlight but i did today. I was taking some new pictures lol.
So I just went to bring it in and there was a 3 inch wet area, wouldn't call it a puddle just wet. It is coming out of 1 of the 3 tubes there, and when I stick my finger in the tube it feels pretty oily but has a very faint smell of gas. What are these 3 tubes for? I know what the engine breather pink tube is, and know there is a fuel overflow tube but this was pretty oily between my fingers.
It's evaporated fuel from the tank that recondensed, ran down the breather, and onto the ground. Several people seem to have this issue in warmer climates (myself included). Only happens to me when left outside in direct sunlight, and does it even at 1/3rd tank.
 

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The best way to find out is to follow them to their source. I cant be bothered as I'm not worried about them as they will just be breather/overflow tubes of some sort.

I was working on my radiator recently and I know it has a black tube coming off just below the cap, so one will be a breather for the radiator.

I'm guessing one will be for overflow/spillage from the fuel tank around the fuel cap area and/or also to let the fuel tank breathe in hot weather allowing for fuel/gas expansion.

The third I don't know but as Mike suggested, something to do with the EFI system maybe.
Perhaps you could trace it and tell us! :D

A bike parked in direct sunlight in hot weather will sometimes push fuel out the tank breather, this is quite common.
 

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Yah I'm positive it was fuel. There is a tiny hole at the very top lip. I tried to push as much fuel as I could as I'm guessing it dripped down the overflow tube. Then parking it in 95 degree Florida sunlight didn't help much either. Definitely smelled like fuel, but it was a little gunky. That's what threw me off, a yellow thick gunk
 

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It's evaporated fuel from the tank that recondensed, ran down the breather, and onto the ground. Several people seem to have this issue in warmer climates (myself included). Only happens to me when left outside in direct sunlight, and does it even at 1/3rd tank.
Pretty much describes my issue 100% here!

The issue is even amplified, when the nights are cold, and the following days are hot. Florida winters the temps dipped to 50F, and the days (on my back porch) the temps raised to a good 90F.

Losing as much as 2 gallons in 4 days, although less when temperature differences between night and day are less.
Perhaps it's good to park the bike indoors.

It also seems to be a problem on the CB500 bikes (CBR500R/CB500F/CB500X)
 

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The best way to find out is to follow them to their source. I cant be bothered as I'm not worried about them as they will just be breather/overflow tubes of some sort.

I was working on my radiator recently and I know it has a black tube coming off just below the cap, so one will be a breather for the radiator.

I'm guessing one will be for overflow/spillage from the fuel tank around the fuel cap area and/or also to let the fuel tank breathe in hot weather allowing for fuel/gas expansion.

The third I don't know but as Mike suggested, something to do with the EFI system maybe.
Perhaps you could trace it and tell us! :D

A bike parked in direct sunlight in hot weather will sometimes push fuel out the tank breather, this is quite common.
The third one with a plug in it is the crankcase breather. The plug should be taken out at each service and any liquids drained off. Then put the plug back in.
 

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Pretty much describes my issue 100% here!

The issue is even amplified, when the nights are cold, and the following days are hot. Florida winters the temps dipped to 50F, and the days (on my back porch) the temps raised to a good 90F.

Losing as much as 2 gallons in 4 days, although less when temperature differences between night and day are less.
Perhaps it's good to park the bike indoors.

It also seems to be a problem on the CB500 bikes (CBR500R/CB500F/CB500X)
2 Gallons???? If you are losing 2 Gallons of fuel in a few days it's not just the hose lol. You have a leak bro.
I have had a few drips when my tank is completely full and its in the direct 90degree sun. Just enough to form a stain on my driveway the size of a quarter
 

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2 Gallons???? If you are losing 2 Gallons of fuel in a few days it's not just the hose lol. You have a leak bro.
I have had a few drips when my tank is completely full and its in the direct 90degree sun. Just enough to form a stain on my driveway the size of a quarter
Round about 1.5 to 2 gal.
It was the cold front 3 weeks ago, with lows in the high 40s at night.
Most days I lose less than that.

I have a stain about the size of a dish plate under the hose.
Most of the fuel is evaporating, however the dripping liquid is a more oily substance smelling like fuel. Confirmed recondensed fuel. It's creeping in the concrete, so I can't wash it off, neither slip over it.

Called Honda headquarters.
I doubt they will do anything about it.
All they need is either get a carbon canister installed there, or get a cork-sealed fuelcap installed like on the Rebel. Either one will probably work for venting the tank.

The Rebel sits in the sun for a month on end, even with the fuel valve opened it loses less fuel than the cbr in one day!
 

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Round about 1.5 to 2 gal.
It was the cold front 3 weeks ago, with lows in the high 40s at night.
I have a stain about the size of a dish plate under the hose.
Most of the fuel is evaporating, however the dripping liquid is a more oily substance smelling like fuel. Confirmed recondensed fuel.

Called Honda headquarters.
I doubt they will do anything about it.
All they need is either get a carbon canister installed there, or get a cork fuelcap installed like on the Rebel. Either one will probably work for venting the tank.
MeeLee: Why don't you take it back to the dealer you got it from and let them check it out. Or is that to much trouble?
 
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MeeLee: Why don't you take it back to the dealer you got it from and let them check it out. Or is that to much trouble?
It's been there for 9 days now.
Mechanic couldn't find anything.
Says everything is normal.
That's why I got Honda headquarters involved.
I'm not the only one with this issue.
Cb500 and possibly Nc700x/nc705x/CN700 also has the same problem.
You can easily find threads started by other users on the 500 forums, with same issues.
It appears that high heat is expanding, and evaporating the fuel.
Not a problem if you live in cold areas or keep the bike stored indoors.
Not a problem when riding the bike either.
Only when standing still in naked sunshine or even under a cover in hot climates, (exceeding 85F).
 

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It's been there for 9 days now.
Mechanic couldn't find anything.
Says everything is normal.
That's why I got Honda headquarters involved.
I'm not the only one with this issue.
Cb500 and possibly Nc700x/nc705x/CN700 also has the same problem.
You can easily find threads started by other users on the 500 forums, with same issues.
It appears that high heat is expanding, and evaporating the fuel.
Not a problem if you live in cold areas or keep the bike stored indoors.
Not a problem when riding the bike either.
Only when standing still in naked sunshine or even under a cover in hot climates, (exceeding 85F).
Mee Lee: Sounds to me like a design fault, I wonder if they do it in Thailand as well seeing that it is made there.
 

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Mee Lee: Sounds to me like a design fault, I wonder if they do it in Thailand as well seeing that it is made there.
That is what I was wondering...there are tons of these bike in Thailand/Indonesia where it gets very hot/humid. You would think it it was a big issue..members here from those areas would have said something by now.
 
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Mee Lee: Sounds to me like a design fault, I wonder if they do it in Thailand as well seeing that it is made there.
If it was a design fault, we would have been talking about this long before MeeLee bought his bike... clearly it is an issue with his bike in particular.

What I don't understand is his claim to be consistently losing so much fuel, and yet he says the mechanic can't replicate the problem at the dealership. Something is not adding up here.
 
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I am sorry Mee Lee...but I find it hard to fathom that you can lose 2 gallons of fuel out of the hoses in a few days.... I am not trying to start a conflict but...2 gallons???
 
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It's been there for 9 days now.
Mechanic couldn't find anything.
Says everything is normal.
That's why I got Honda headquarters involved.
I'm not the only one with this issue.
Cb500 and possibly Nc700x/nc705x/CN700 also has the same problem.
You can easily find threads started by other users on the 500 forums, with same issues.
It appears that high heat is expanding, and evaporating the fuel.
Not a problem if you live in cold areas or keep the bike stored indoors.
Not a problem when riding the bike either.
Only when standing still in naked sunshine or even under a cover in hot climates, (exceeding 85F).
Yah man, I know exactly what you're talking about but I only get a few drips. And it is an oily-fuel kind of liquid. Its just the fuel overflow tube. Under your gascap there is a hole and when it's hot it, especially a full take of gas I guess things expand and it drips down that hole, down the tube and drip drip. I would say don't leave the bike in the hot Florida sun for a week straight and you wont lose as much gas lol
 

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Unfortunately that's not an option.
On my Suzuki, the tube would connect to a vacuum hose towards the air filter.
The oily substance would be captured by a sponge on the bottom of the oil filter.
The bike would start, and suck up the fumes, and the sponge would release the fumes over the startup period, resulting in a richer, less painful start, where often I'd not need the choke.

Honda needs to recall this bike!

Either install a carbon canister to capture the fumes, or install the hose to the airbox. Easy fix if the airbox has a mounting hole.
It'll allow the bike to run richer at startup, not that it matters with fuel injection anyway...

I really did lose 2 gal over 4 days.
On average it is more like a quart a day.
The mechanic saw what I talked about, but wasn't able to replicate the 2 gallon loss, because it wasn't cold enough at night.
Honda doesn'tthink it's an issue, until the first lawsuit comes up of one guy who burned his bike due to the fumes catching fire....

My bike does stand in a corner of a white walled house, that does intensify the temps when the sun shines there (usually from 9 or 10am to 4pm).
 
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