a case of poor/bogging down accelleration.

[TjTexasJack]

Conkankerous has deveoped a case of poor/bogging down accelleration.

Here's the pre problem happenings.

Switched to reserve Sunday and put about 21 miles on bike.
Monday bike ran fine on trip to work. (8miles)
After work on way home bike ran fine stopped for cold one at fav watering hole.
Went back out fired it up and was bogging down when I accelerated.
Needs gas I think and filled it up. Still bogging down.
Bike starts and rev's just fine.

Here's what I've checked and done so far.

Replaced fuel lines and filter. (Just a few tiny specks in filter and its been in there two years.)

Checked vac line and vac plugs all good.

Checked tank vent. Good

Drained and checked levels floats and no trash. Good. (Had just done that two weeks ago.)

Checked plug wires and plugs. All good and all four headers are getting hot.

Checked air filter- so so. Ran bike with out it. No help. Air box did not have gas smell

Checked for vac to petcock. Good, But had a pulse feeling in it. Ran bike on prime. No help.

Checked all carb boots. Looked ok, But time for some new ones.

Going to grab some seafoam and drain the gas out tommorw. 7 gallons is a heck of a lot lawnmower gas. Lol

Thanks in advance.
Tj

[George R. Young]

Blind guesses:
1) clogged main jet?
1.5) main jet fell out?
2) torn diaphragm?

I believe these can be checked thru the top of the carb, so you might not have to drain the 7 gallons.

[MAN OF BLUES]

Switched to reserve Sunday and put about 21 miles on bike.
Monday bike ran fine on trip to work. (8miles)
After work on way home bike ran fine stopped for cold one at fav watering hole.
Went back out fired it up and was bogging down when I accelerated.
Needs gas I think and filled it up. Still bogging down.
Bike starts and rev's just fine.
...

flipping to reserve, and running on it for as long as you did (40 miles with sets in between) certainly allowed any and all moisture in the tank to go straight to the primary low speed circuits, and gum it all up.

then, adding a full tank of fuel, on top of that, when the bike is suspect already, without adding a hefty dose of drygas, teaches us about just how heavy that full gastank is...

Pass on the SeaFoam...at this point...
Add IsoHeet or HeeT dryer to it, a full bottle, or even 2, and run it.
http://www.goldeagle.com/brands/heet/faq.aspx

you know what happened, and it is very unlikely to be a "sudden mechanical part failure", as much as a "degradation due to fuel" issue.

[kbecker3]

I had a 81 GS750 that did that one day. I narrowed it down to the fuel line got just warm enough to become pliable enough to kink and restrict just enough fuel to make it bog down. The way the fuel line was ran on the GS reminds me of the way the one on the concours is ran. On the GS they have a spring that goes around the fuel line that is supposed to help prevent kinking, i ended up putting one of those on the fuel line. I have not had that isue on the concours though.

Maybe same problem, maybe not. but another thing you can check.

[Cholla]

Yeah, let's add more alcohol to the gas to attract even more water.
Drain the tank, remove and clean the petcock as it may be blocked.
When I first saw this thread I thought torn carb diaphragm, too.
Drain tank, etc, add a couple gallons fresh gas with some carb cleaner and ride. If symptoms persist a carb cleaning is in order.

[snarf]

Have you done any 'work' to the vac system? The reason I am asking is that I had a very similar issue on my 86.  It turns out that all the vac lines were tee'd together.  Under acceleration the vac from opposing cylinders were basically canceling the vac and allowing the petcock to close slightly starving the bike of fuel.  HTH 

[TjTexasJack]

Happy Friday Everyone.

Got Slammed at work sooooo will dig into this more this weekend.

Had some Isoheat on hand and dumped that in. With only 5/6 miles on treatment no/little change.

Pulled the plugs and all four are a nice tan color. (Was hoping one would be discolered and point the direction to look. Grrrrlol.) It may just me my old eye's, But 3 and 4 looked just abit darker.

Snarf. Conkankerous had been converted to caps and single vaccume line to petcock when I got him. Going to grab three new cap's tommorow just to cover all bases.

Going to drop the float covers tonight mostly so I can say I did. What's the advantage of doing that?

Also going to take the top's off and peek in there.

No problem in yanking the carbs and rebuilding them. I'm not a SISF, But can rock that it's just a PITA.

Thanks in Advance for any help.
Tj

[MAN OF BLUES]

Yeah, let's add more alcohol to the gas to attract even more water.

therein lies the simple problem....the addition of the substance is only one part of the equation.....

Happy Friday Everyone.

Got Slammed at work sooooo will dig into this more this weekend.

Had some Isoheat on hand and dumped that in. With only 5/6 miles on treatment no/little change.

IsoHeet does not magically dispell the water, it binds it up in the fuel solution, so it CAN be BURNED instead of sitting as globs in the tank.
It IS necessary to run the bike, under load, for some time, to burn the fuel up and effect the desired remedy.
Other than that, completely draing the tank, and the bowls, and using Fresh fuel from a NEW clean gascan, and adding the Isoheet, taking it for a 100 mile ride will complete the venture.

simply adding a substance of any kind, to the fuel, and allowing it to sit, will not do a thing.

I did give a link, that explained this.....

Q: How does HEET work?
A: HEET contains a special additive and methanol. When HEET is added to the gas tank, it sinks to the bottom and mixes with any water. Since both HEET and water are heavier than gasoline, they go to the bottom of the gas tank. HEET absorbs water and keeps it from freezing, and blocking the flow of gasoline through the gas line and fuel pump. When the vehicle is started, the additives, methanol, water, and gasoline are consumed during combustion inside the engine.


Q: How does Iso-HEET work?
A: Iso-HEET contains isopropanol and special additives including Fuel Injector Cleaner. When Iso-HEET is added to the fuel tank, this formula remains in the solution with the gasoline, and absorbs five times more than regular gas-line antifreeze. Any water in the gas tank mixes with the Iso-HEET, preventing the water from freezing in winter. Iso-HEET also removes water and condensation in warm, wet weather. Then the entire mixture of gasoline, Iso-HEET and water are burned during combustion inside the engine. Iso-HEET cleans fuel injectors and carburetors for fast starts and smooth-running engines year round.

[Cholla]

No need for the isoheet after draining and cleaning the tank. No water left to absorb. Use a good fuel system cleaner instead. Adding alcohol to the fuel will magically attract more water if left in the tank.

[TjTexasJack]

Sry to take so long reporting back.

Well as stated I had pulled the plugs. Went ahead and trimed the wires down and check resistor conectors. All clean with the exception of #1.

While I had tank off when ahead and inspected the internals of top of carbs. Diaframs all good and the valves/slides where operating smooth. Sprayed some seafoam down the needle/jet opening.

While I had removed most of the gas there was about a gallon left in the bottom.

Tell of the gas: (Done by draining samples from the bowls.)

Original sample showed no visable water or junk.

Original sample with IsoHeet added. A build up of a white fuzz/Gunk. I AssUme Isoheet binding the water.

Drained tank 1 gallon left, three new gallons added. Still some white gunk. Bike still not runing right.

Completely drained the tank, rensed with gas. Added two gallons, drained the bowls. Bike runs like a top maybe even better than before.

Thanks for all the Input and help.

Any ideals on how to get rid of  10 gallons of crappy gas? Lol

Tj 

[MAN OF BLUES]

No need for the isoheet after draining and cleaning the tank. No water left to absorb. Use a good fuel system cleaner instead. Adding alcohol to the fuel will magically attract more water if left in the tank.

RIGHT.  So I have been sooooo wrong in telling folks to do this year after year.....thanks....
   
I will simply state as I have many many times before, that it is incorrect to think adding IsoHeet will cause more problems with water....it simply ain't so, and if done correctly, and THE FUEL MIXTURE IS BURNED there is no issue.

Sry to take so long reporting back.

Well as stated I had pulled the plugs. Went ahead and trimed the wires down and check resistor conectors. All clean with the exception of #1.

While I had tank off when ahead and inspected the internals of top of carbs. Diaframs all good and the valves/slides where operating smooth. Sprayed some seafoam down the needle/jet opening.

While I had removed most of the gas there was about a gallon left in the bottom.

Tell of the gas: (Done by draining samples from the bowls.)

Original sample showed no visable water or junk.

Original sample with IsoHeet added. A build up of a white fuzz/Gunk. I AssUme Isoheet binding the water.

Drained tank 1 gallon left, three new gallons added. Still some white gunk. Bike still not runing right.

Completely drained the tank, rensed with gas. Added two gallons, drained the bowls. Bike runs like a top maybe even better than before.

Thanks for all the Input and help.

Any ideals on how to get rid of  10 gallons of crappy gas? Lol

Tj

good job man, glad you decided to try it out, and not listen to speculation...

[Cholla]

MOB-in your quest to be correct you failed to read what I said and you even said. After draining the tank it is EMPTY. What water is there to absorb? Now you add alcohol...what happens after he puts gas in the tank that is probably already 10% alcohol, drives it and then it sits for a few days or weeks? The alcohol in the fuel attracts water!
You ignored my statement about the tank being EMPTY and you fail to notice the water in the fuel had turned to a goo in the tank the engine couldn't burn.
That is why I said to drain the tank and clean the petcock. He failed to drain in completely the first two times and the alk/water junk remained. It ran perfectly after the tank was rinsed of the alk/water mix. Once you get to a certain poit adding alcohol makes matters worse as in this case. In fact, Connie doesn't like alcohol. Too much and it won't run. It doesn't have the compression and its not jetted for it.

[Daytona_Mike]

IsoHeet is made from Isopropanol. Most gasoline today  contains 10% ethanol which  improves the octane level (better for high compression engines) but ethanol has less energy per volume . Both can absorb  a small amount of water but  Isoheet is much better at it.
Neither one of these will  'attract'  more water especially if   Isopropanol  is added to gas anymore than steel  or rocks attract water and as long as the recommended amounts are added to gasoline  it will not affect performance in fact race fuel is mostly methanol and  we all know  how well that performs. Bottom line is alcohol attracts alcoholics and not water. How silly would it be for a product to designed  prevent  frozen fuel lines caused by water if it  really just   'attracts'  more water?

[Cholla]

That's odd...the race fuel we use in the late model has ZERO methanol. It is GASOLINE.
Now we also use straight alk in the modified.