backing off

[sambo]

ok its doing it again

what i originally thought was water in the tank causing the bike to back off under load has come back to bite me in the ass again.

theres no way it can be water in tank now cos ive drained the tank let it dry out and kept it in the garage all the time

this may sound strange but it only does it in 4th 5th when there is a strong head wind, but it cant be the wind causing the bike to slow as the revs are to high. i think its gonna be fuel starvation or coils packing up :confused:

[MikeG]

Can it be something as obvious as the air filter, or even the rubber trumpets on the air box that have been known to "turn round" of thier own accord, thus causing air starvation.

OK its a long shot...

[sambo]

trumpets facing forward, new air filter and plugs less than 500m ago and its a real ba++++d when you go to over take and its backing off

[MikeG]

Has the bike got standard pipes, or something else? Just thinking about possible need to change jets.
Are the carbs worn?

Thinking...

[CK & AK]

If you get really stuck, and have access to a trailer......
we are going to be in North Cornwall from this Sat for 2 weeks.

AK is already doing some carbs & jetting for a DSC member while we are down there, and possibly a service on another too, so the tool box is going into the van, along with the bikes.

Drop me a u2u if still got probs, but before Fri nite, as wont be on line for quite a while after....

[sambo]

the bikes only done 14.5 k the exhausts are standard but the chap who owned the bike before has cut the pipes down by about 2 inches apart from that the bike is in really good condition :confused:

the bike still works it only backs off maybe 3-4 times on a 50m run

[BoozyBOB]

have the same prob with mine...about 5k and it seems to want to die for a few seconds...try the tank breather tubes..could be kinked or blocked...
only does this when i have done over 70 miles on one tank.. :confused:

[Sparky]

Could be the fuel filter needs replacing. Sounds more like fuel starvation rather than coils to me.

Chris

[sambo]

startin to look more on the fuel side of things, as it would be more probable that shes runin dry on the gas than coils breakin down :eek:

[gary tompkins]

Sounds like fuel starvation to me too. Check for muck/water in the carb float bowls or blocked filters and breathers.

When you say the standard cans were cut down i'm assuming they have had the guts removed as well. This may have effected the carburation - maybe not enough to cause the engine to die but still worth checking.

Carb icing can also cause weird symtoms like this, but it's a bit early to suffer with this yet. Another couple of months and you'll be needing to dose the engine with FST Pro to avoid cold weather problems.

[sambo]

gonna strip the carbs today a check the fuel filter any other ideas while im at it would be spot on :)

[BlueHaze]

As others have said, check the tank vent/breathers as it sounds similar to a common problem with bikes of the tank vent being blocked.

Does there seem to be some suction when you open the tank cap to fill up?
As an experiment you could open the tank filler cap each time you go out for a ride to let some fresh air in and see if the problem still occurs.

[sambo]

cant say i have had suction from tank on filling up but will also check it out :burnout:

[sambo]

and i found

1 tank breather pipe kinked
1 carb float sticking
carbs full of s**t
fuel line full of the same s**t

and for good measure i cleaned everything i came across, i think this should do it all i have to do is take it for a ride.

cheers for all the ideas people wouldnt have found all that on me tod

sam :)