Setting the carbs

[cabreco]

The previous owner had the carbs were synced by Muffinman last summer. She runs great but I feel she is eating too much gas.

 

Does anyone have a write up of what I would need to do & what I would need to have on hand (equipment wise) other than a screwdriver to decrease the feul intake? Would the carbs need to be synced again if I do?

[utadventure]

Andy-

 

What MPG are you getting and at what speed?

 

Are the sliders moving? You can see them move by lifting off the air cleaner cover and looking down into the carbs. If not gently pry them back with a screwdriver to free them up. They may be stuck a bit. Don't try to just pull them out from the diaphram side, you're likely to break the slider.

 

The '84 usually gets pretty good mileage. If you don't you may consider doing the carb needle shim modification. Some early carbs had an adjustment on the needles but the latter Ventures can be adjusted by changing the thickness of the washers on the needles.

 

It's easier than you might think and it's done by removing the diaphrams. Just search for the mod here on the website.

 

You can also adjust the mixture screws on the outside of the carbs, centered under the diaphram covers. They may be behind a plug.

 

Good luck!

 

Dave

Edited February 27, 2012 by utadventure

[cabreco]

Right now most of my driving has been below 50 mph. I haven't done an exact calculation, but like I said I have gone through 1/2 a tank in less than 75 miles. So at best I would say I'm getting under 30 mpg?

[MiCarl]

Right now most of my driving has been below 50 mph. I haven't done an exact calculation, but like I said I have gone through 1/2 a tank in less than 75 miles. So at best I would say I'm getting under 30 mpg?

 

You need to buy gas to see. On my 89 when the gauge reads 1/2 I haven't used more than 1/3rd.

 

I answered your other post.

[dacheedah]

I agree, the only eay to know how much gas is in her is to fill it up, mark the mileage and run it on reserve until you run it dry. You will know the mileage and how much you actually used so your actual miles per gallon will be spot on. Have a spare gallon or 2 with you to get running again. and you will know with confidence where you are at.

[MiCarl]

I agree, the only eay to know how much gas is in her is to fill it up, mark the mileage and run it on reserve until you run it dry. You will know the mileage and how much you actually used so your actual miles per gallon will be spot on. Have a spare gallon or 2 with you to get running again. and you will know with confidence where you are at.

 

You don't have to run it dry to get mileage. Just top it off, ride 50 miles, fill up and do the math.

 

The capacity is a bit over 5 gallons so you then should have an idea your range.

[muaymendez1]

I rode 208 miles one day on a tank. I was trying to see at what point the fuel light comes on.

I couldnt take it . the fear of getting stranded was killing me so i pulled into a gas station and Put some fuel in.

Before that I was filling up at 160 worried I was gonna run out of fuel .

4.9 gals 208 miles , I got 42 mpg and who knows if 10 feet away from the gast station driveway i may have run dry?

Im happy with 42 run it on the reserve setting. Do some all around riding . Your highway and your street milage will differ. Sometimes greatly

[dacheedah]

I agree you can get the mileage with a short fill up but I believe you will get a more accurate snapshot of the MPG by running more gas through it.

 

I would also argue that the quality of gas is different at different stations and that will effect your mileage. I am talking formulation from station to station and not higher octane. We were having problems with our boats running rough and with fuel problems and it ended up being three gas stations in our town. The end result was lower octane, water and a higher than 10% ethanol. After testing all the stations through the summer there are simply some places I won't go for gas. Gas like beer is not all the same. You can order test kits several places or find instructions for testing gas. Saving a few bucks in the front end may cost you big in the back end. I ended up having to replace all my fuel hoses on my e-tec and simply changing stations with lower ethanol has proven to make a difference.

[Venturous Randy]

Andy, after doing the needle/washer adjustment and new diaphragms on my 83, I have got as good as 49 mpg when running 2-up and running in the 50 mph range. Also, this has been with no loss of power.

RandyA

[cabreco]

...Are the sliders moving? You can see them move by lifting off the air cleaner cover and looking down into the carbs. If not gently pry them back with a screwdriver to free them up. They may be stuck a bit. Don't try to just pull them out from the diaphram side, you're likely to break the slider.

 

Dave,

 

I've got a whole can of carb cleaner ready for the job today. I have been running seafoam for the last 2 tankfuls to clean stuff out. I also suspect something might be out of whack as the bike wreaks of gas when I park her in the garage after a ride. Within a few hours (and opening up the garage door to vent) the gas smell subsides.

I haven't found a leak yet

 

Since I have to replace my gas filter, I figure I will also replace the fuel lines from the petcock through to the carb since they ARE OEM.

 

BTW does anyone know if I HAVE to use a Yamaha filter or will any generic auto filter fit?

 

Hopefully, a good cleaning, new fuel line & filter will resolve the MPG & gas smell!

[Condor]

Right now most of my driving has been below 50 mph. I haven't done an exact calculation, but like I said I have gone through 1/2 a tank in less than 75 miles. So at best I would say I'm getting under 30 mpg?

 

And you're runing in fifth gear to get better millage... Right??. Kick it down into 4th and see what happens. It's a weird phenomena with these motors, they get better MPG with higher RPM's.... Ya can't lug them and expect 40mpg....

[utadventure]

Dave,

 

I've got a whole can of carb cleaner ready for the job today. I have been running seafoam for the last 2 tankfuls to clean stuff out. I also suspect something might be out of whack as the bike wreaks of gas when I park her in the garage after a ride. Within a few hours (and opening up the garage door to vent) the gas smell subsides.

I haven't found a leak yet

 

Since I have to replace my gas filter, I figure I will also replace the fuel lines from the petcock through to the carb since they ARE OEM.

 

BTW does anyone know if I HAVE to use a Yamaha filter or will any generic auto filter fit?

 

Hopefully, a good cleaning, new fuel line & filter will resolve the MPG & gas smell!

 

Each carb has an overflow drain tube. If you have something (crud) not allowing the float to function properly, you are probably getting overflow when the bike is running. The overflow tubes run down and come out by the center stand, in front of the rear wheel. There may be 4 tubes or all joined into one tube. Sometime a few sharp taps on carbs with the handle of a screwdriver will break it loose, I finally had to give a short blast of air back up through the drain line. (watch out for the fuel that sprays up through the air cleaner!!) I haven't had an issue since.

 

Dave

[cabreco]

And you're ruining in fifth gear to get better millage... Right??. Kick it down into 4th and see what happens. It's a weird phenomena with these motors, they get better MPG with higher RPM's.... Ya can't lug them and expect 40mpg....

 

REALLY??? I would not have expected that. You would think 5th would be overdrive.

I'll give that a shot around town (I actually would prefer it there as get outta the way gear)

 

Each carb has an overflow drain tube. If you have something (crud) not allowing the float to function properly, you are probably getting overflow when the bike is running. The overflow tubes run down and come out by the center stand, in front of the rear wheel. There may be 4 tubes or all joined into one tube. Sometime a few sharp taps on carbs with the handle of a screwdriver will break it loose, I finally had to give a short blast of air back up through the drain line. (watch out for the fuel that sprays up through the air cleaner!!) I haven't had an issue since.

 

Dave

 

No overflow at all. I pulled all 4 overflow lines & made sure they were clear. I also clipped the fuel line 3/4" back to get a nice seal. My carbs were rebuilt by the P.O. & synced by Muffinman but I figured cleaner can't hurt. I sprayed a whole can of carb cleaner in, on & around the carbs. They were working before but if not the sliders are definitely moving now.

 

After cleaning I did notice one thing (which has made me happy) The bottom boot between the engine & the right rear carb seemed to be loose. I say seemed because I saw a slight weeping if gas on the side of the boot while running. I loosened the clamp cleaned it all up, made sure the clamp was positioned correctly & tightened the clamp down. No more weep.

 

I took the bike for a 1/2 hour ride, came home & closed the garage door. After 45 minute I checked on her & although the garage stinks from all the carb cleaner & junk I used, it is not that overpowering "I think the water heater will ignite the gas fumes" smell.

 

Now I'm off to clean the garage. I think I finally fixed the smell, let's see what the mileage does!

[cabreco]

Well so far I have 120 miles on the counter & the red light if fluctuation between flashing red & solid red. I'm not on reserve so if I run out of gas I can flip it to reserve.

 

I'll post my miles when I flip it over to reserve

[Yamamike]

:

Each carb has an overflow drain tube. If you have something (crud) not allowing the float to function properly, you are probably getting overflow when the bike is running. The overflow tubes run down and come out by the center stand, in front of the rear wheel. There may be 4 tubes or all joined into one tube. Sometime a few sharp taps on carbs with the handle of a screwdriver will break it loose, I finally had to give a short blast of air back up through the drain line. (watch out for the fuel that sprays up through the air cleaner!!) I haven't had an issue since.

 

Dave

 

:sign yeah that::sign yeah that

[cabreco]

:

 

:sign yeah that::sign yeah that

 

 

Mike & Dave you guys cursed me

 

I have run her in the driveway & around with little bags tied to the overflows & they are dry. I did check & the tubes are clear of obstructions.

 

I got as far as 130 miles before she sputtered & I had to switch her over to reserve.

Then the fun began

 

One of the overflows started pissing like a racehorse! I could smell it as I rode. Maybe this was a good thing. I took out that precision calibration tool, my handy dandy shade tree mechanics instrument (a hammer) & gave that carb a few taps & she immediately stopped leaking.

 

Now 130 miles seems low, although I do not know the range of the reserve tank (& do not want to find out 1st hand). Since I have a complete extra carb bank from the parts bike I will rebuild that.

 

Can anyone point me to a good source for a rebuild kit & what part number etc I should refer to?

What to they usually go for?

[utadventure]

Mike & Dave you guys cursed me

 

I have run her in the driveway & around with little bags tied to the overflows & they are dry. I did check & the tubes are clear of obstructions.

 

I got as far as 130 miles before she sputtered & I had to switch her over to reserve.

Then the fun began

 

One of the overflows started pissing like a racehorse! I could smell it as I rode. Maybe this was a good thing. I took out that precision calibration tool, my handy dandy shade tree mechanics instrument (a hammer) & gave that carb a few taps & she immediately stopped leaking.

 

Now 130 miles seems low, although I do not know the range of the reserve tank (& do not want to find out 1st hand). Since I have a complete extra carb bank from the parts bike I will rebuild that.

 

Can anyone point me to a good source for a rebuild kit & what part number etc I should refer to?

What to they usually go for?

 

You may have knocked the obstruction loose on the float (at least you know which one it is now). Run some more seafoam through it and you could be just fine.

 

Maybe drain the float bowl a couple of time and it may flush out there.

 

I usually get to 125-130 when the reserve light comes on. I run with the valve in the reserve position, so I don't know if it's still on the main or into the reserve. When I fill up it's about 4.3 gallons.

 

Dave

 

 

 

[cabreco]

I usually get to 125-130 when the reserve light comes on. I run with the valve in the reserve position, so I don't know if it's still on the main or into the reserve. When I fill up it's about 4.3 gallons.

Dave

 

So while NOT on reserve position, the flashing red light begand at about 100 miles. I ran it to 130 befor it ran out & I had to flip to the reserve position. I filled the tank to the bottom of the neck it was 4.648 gallons.

 

133 miles/4.648 gallons = 28.6MPG

 

This is local driving only, mostly under 50mph (suburbia). So... would you guys say that this mpg would be about right?

 

I am hoping that interstate driving is at least 35mpg.

[frankd]

Every First Gen gas gauge is slightly different, but.....both my 83 & my 89 are pretty close to each other. When my reserve lights come on solid, they both need about 3.9 gallons to fill them up. That means (on my First Gens) that I still have almost 1.5 gallons left, so I usually travel another 50 miles before I fill up, and they will need abut 5 gallons and I'll have about 210 miles on the odometer, as long as I'm travelling less than an indicated 75 MPH (72 on the GPS).

 

On your bike, the reserve light was almost on solid, and you had 120 miles. If your gas gauge is calibrated about like mine, it would have needed 4 gallons to fill, and you would have gotten 30 MPG----which was about what you found out when you filled it up. The needle leaking and the carb bowl overflowing isn't new. You've been smelling that every time you parked it in your garage. Keep an eye on it and if it re-occurs, turn the fuel tank petcock to OFF and ride it on side streets until the carbs are completely empty. Then turn on the petcock turn the key ON and rock the kill switch back and forth to keep the pump running until the carbs refill. THis may flush the garbage that's making your carb overflow off the needle and seat. If not, you'll have to pull the float bowl and clean it out. Curing this will help your gas mileage quite a bit.

 

Frank D.

[cabreco]

Well the overflows have been ok since the day I ran dry BUT now the bike seems to be stinking after a ride. I'm sure it's related to the what ever obstruction caused the overflow. I'm sure a float is stuck.

 

I have run seafoam in the tank before. I know you can soak the carbs by running a gas/seafoam mix. Since I'm going to be replacing the gas filter I figure I would run a mix in a jar through the pump into the carbs. a 50/50 miix I have heard works, has anyone tried using less gas & more seafoam??

 

I gotta get this fixed once & for all!

[cabreco]

Well whatever it was stinking up the carbs...is GONE. I again sprayed carb cleaner down the carb throats until she was puffing white smoke out the tail.

I dumped 1/2 can of Seafoam in the full tank, then I went to the Yamaha dealer fro fork oil. Drove a total of 70 miles on the highway at 70mph.

By the time I got back, I put the bike back in the garage. I checked on her a 1/2 later an no gas smell.

 

I guess there was a stuck float.

 

Driving around Norfolk, where the cement roads are not the greatest, I realize how much I really needed these springs. All I heard was "clunk clunk clunk"

 

Now to install the Progressives I got from Skydoc17!

[GaryZ]

So while NOT on reserve position, the flashing red light begand at about 100 miles. I ran it to 130 befor it ran out & I had to flip to the reserve position. I filled the tank to the bottom of the neck it was 4.648 gallons.

 

133 miles/4.648 gallons = 28.6MPG

 

This is local driving only, mostly under 50mph (suburbia). So... would you guys say that this mpg would be about right?

 

I am hoping that interstate driving is at least 35mpg.

 

Less than 30MPG is unusual for a 1st Gen. Mid-40s seems to be more typical with some guys getting 50. My Beast is running no less than 30 around town and 34+ on the highway, and a best of 42 carrying a passenger to Kerrville, TX at speed. This seems to be more typical of a Vmax. Oh wait, I have Vmax cams! Anyway, there may be something to the comment about better MPG at higher RPM. I plan on experimenting this summer.

[cabreco]

Less than 30MPG is unusual for a 1st Gen. Mid-40s seems to be more typical with some guys getting 50.

 

I'm thinking that the bike may be running rich. I'll run a fuw more tanks of Seafoam & then see how she does.

[KIC]

I got 34 MPG on my 89 when I filled up today. This is lower than I was getting on past tanks. I'm thinking that SeaFoam lowers the mileage. I went heavy on the Seafoam on the last tank. The tank I filled up with today will not have any additives. We'll see if it makes a difference.

[cabreco]

So while NOT on reserve position, the flashing red light begand at about 100 miles. I ran it to 130 before it ran out & I had to flip to the reserve position. I filled the tank to the bottom of the neck it was 4.648 gallons.

133 miles/4.648 gallons = 28.6MPG

 

Ok so on this tankful's mileage seems to have improved a bit (we'll see whan I fill up)

So far I've gone 101 miles and I have 2 bars left. Last tank I was flashing the red light at the 100 mile mark. (I'm using Condor's suggestion & running in 4th around town using 5th only for the highway)

 

Now with 2 bars left, I should at least get another 50 miles more before the red light flashes, a bit more if I wait until the red is solid.

 

Next tank will have ABSOLUTELY no Seafoam in it. I know Seafoam does reduce the MPG's & I dumped a 1/2 a can in this tankful.