Carbs and Poor starting
Discussion
Morning,
I have a 2002 900 diversion, 95k miles on it - choke bar hasn't worked in years.
When really cold I sit the hair drier under the fuel tank to unfreeze any droplets in the jets - then starts first time.
Weather is not cold anymore but there is still a reluctance to start - 10 mins or so. It might cough for a bit and then nothing eventually the cough become a few coughs then if held on the starter a steady cough, then it will start.
I have had the same issue with an old car where a potential pin hole somewhere in the pipe / tank system is causing the fuel to drain backwards so the pump has to work for 10 mins to drive fuel to the engine.
Why with a full tank sitting above the carbs would the bike exhibit the same fault / issue ?
To stop at a petrol station is starts first time, to start it at 5pm to drive home again "normally" first time, but if left a day or two, it is reluctant.
As it runs fine, and starts after a short stop, I am working on the basis that it gets a good spark, it has air, so it must be fuel related ?
thanks
Del
I have a 2002 900 diversion, 95k miles on it - choke bar hasn't worked in years.
When really cold I sit the hair drier under the fuel tank to unfreeze any droplets in the jets - then starts first time.
Weather is not cold anymore but there is still a reluctance to start - 10 mins or so. It might cough for a bit and then nothing eventually the cough become a few coughs then if held on the starter a steady cough, then it will start.
I have had the same issue with an old car where a potential pin hole somewhere in the pipe / tank system is causing the fuel to drain backwards so the pump has to work for 10 mins to drive fuel to the engine.
Why with a full tank sitting above the carbs would the bike exhibit the same fault / issue ?
To stop at a petrol station is starts first time, to start it at 5pm to drive home again "normally" first time, but if left a day or two, it is reluctant.
As it runs fine, and starts after a short stop, I am working on the basis that it gets a good spark, it has air, so it must be fuel related ?
thanks
Del
Sounds like fixing the choke would be the ideal solution.
My 2 carb'd bikes need some kind of choke to start unless warm (as in just been running, not just a warm day).
I say 'kind of' because the Monster has FCR carbs without chokes but it needs a couple of 'squirts' of fuel down it using the accelerator pumps or it won't start and then it splutters and coughs until there's a bit of temperature in it. The Guzzi on the other hand needs choke to start but then straight off or it bogs down.
But if it's not been serviced for 65,000 miles it could probably do with some TLC...
My 2 carb'd bikes need some kind of choke to start unless warm (as in just been running, not just a warm day).
I say 'kind of' because the Monster has FCR carbs without chokes but it needs a couple of 'squirts' of fuel down it using the accelerator pumps or it won't start and then it splutters and coughs until there's a bit of temperature in it. The Guzzi on the other hand needs choke to start but then straight off or it bogs down.
But if it's not been serviced for 65,000 miles it could probably do with some TLC...
catso said:
Sounds like fixing the choke would be the ideal solution.
My 2 carb'd bikes need some kind of choke to start unless warm (as in just been running, not just a warm day).
I say 'kind of' because the Monster has FCR carbs without chokes but it needs a couple of 'squirts' of fuel down it using the accelerator pumps or it won't start and then it splutters and coughs until there's a bit of temperature in it. The Guzzi on the other hand needs choke to start but then straight off or it bogs down.
But if it's not been serviced for 65,000 miles it could probably do with some TLC...
Do what to it !!My 2 carb'd bikes need some kind of choke to start unless warm (as in just been running, not just a warm day).
I say 'kind of' because the Monster has FCR carbs without chokes but it needs a couple of 'squirts' of fuel down it using the accelerator pumps or it won't start and then it splutters and coughs until there's a bit of temperature in it. The Guzzi on the other hand needs choke to start but then straight off or it bogs down.
But if it's not been serviced for 65,000 miles it could probably do with some TLC...
The oil leaks keeps the rust at bay....
If it was valve clearances, the problem would be there all the time, irrespective of how long its been sat IMHO
Sounds like to me either the fuel bowls are empty or its flooded, either way I think your on the money with fueling, carb bodies, needles and all those moving parts within do eventually wear and as they do, cause many issues, fuel tap as mentioned worth checking too.
Ive recently replaced the fuel tap and cleaned/rebuilt the carbs on my LC to cure the problem I had with staring it end of last year, would only start by bumping it after sat for a day(was flooding)...Now it starts second kick.
Sounds like to me either the fuel bowls are empty or its flooded, either way I think your on the money with fueling, carb bodies, needles and all those moving parts within do eventually wear and as they do, cause many issues, fuel tap as mentioned worth checking too.
Ive recently replaced the fuel tap and cleaned/rebuilt the carbs on my LC to cure the problem I had with staring it end of last year, would only start by bumping it after sat for a day(was flooding)...Now it starts second kick.
Wedg1e said:
Seems unlikely to me that the floats would suddenly go out of adjustment. What, all of them?
I'd be tending towards an electrical glitch, especially as it seemed to just start randomly.
Even earth connections can suddenly go high-resistance with a bit of damp about.
If just one carb is leaking fuel into the cases, then Yes, in the same way you never find all valves go out of adjustment, only takes 1 to cause a drop in compression on a cylinder.I'd be tending towards an electrical glitch, especially as it seemed to just start randomly.
Even earth connections can suddenly go high-resistance with a bit of damp about.
From what the OP says,it doesnt start randomly, its just when sat for longer periods of time, we'll find out when the OP reports back eh?
d to start, it would just crank and crank and crank. With my bike it was the valve clearances that were out. Similar milage to you too
podman said:
If just one carb is leaking fuel into the cases, then Yes, in the same way you never find all valves go out of adjustment, only takes 1 to cause a drop in compression on a cylinder.
From what the OP says,it doesnt start randomly, its just when sat for longer periods of time, we'll find out when the OP reports back eh?
Doh, I read two near-identical threads and then replied to them both in the one post From what the OP says,it doesnt start randomly, its just when sat for longer periods of time, we'll find out when the OP reports back eh?
I still say all the floats wouldn't go out of adjustment on a multiple bank of carbs at the same time, though yes, one flooding wouldn't help it start. And clearly he needs to fix the choke
The electrical glitch reference was in response to the 'R6 poor starting' thread. Black-K1 said much the same, I was just agreeing with him.
Valves generally tend to hammer down and get tight, rather than loosen up, so if you have tight valves on startup you will be losing compression, which is a common cause of hard starting.
Once fired the valves heat up, grow a little in length and stay sealed for a while.
Spinning it over for a while might be enough to get them wet with fuel, and thus seal better.
My advice, do some bloody maintenance so you don't have to dick about with hairdryers and ten minutes of starting.,
Once fired the valves heat up, grow a little in length and stay sealed for a while.
Spinning it over for a while might be enough to get them wet with fuel, and thus seal better.
My advice, do some bloody maintenance so you don't have to dick about with hairdryers and ten minutes of starting.,
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