Runs and then stops grr

when it next does it you need to pull the plug and check for a spark and also for the smell of fuel around the plughole area. check the pick up to flywheel gap.

does sound like something electrical cries 'enough' doesn't it?

regards

taffy

It very well could be that your have a vacuum lock problem with your gas tank. Make sure that the cap and vent line are clear. If you have one of those swivels with the vent line that could be the problem.

If it is convenient for you, don't do anything, take it for a ride and when it dies just take the gas tank cap off and see if it restarts. Then you will know for sure. I've seen this happen quite a few times.

Dale

Check for varnish in the petcocks and petcock screens in the tank.

Cmags said:

Hi guys

I have a 04 650fse. Following a main bearing failure and rebuild I'm having major issues with this thing.

Basically the ignition cover and pickups have been replaced, new plug and lead. Stator was rebuilt I believe. The bike will start fine and run for about 4 mile, then dies, then no joy starting unless you leave her for 5 mins then she will start again and then die a few seconds later and this I the pattern then. Now petrol was left in the carb for quite a while and did turn to that varnish type stuff, but carb has been cleaned.

Any ideas, it is the carb or ignition end?? Helpppp!!

Click to expand...

After reviewing my post I see that I did not address your question.

It does not sound like it's a problem with the carb, if it was it wouldn't run right from the get go. However, it does display the classic bad stator characteristics of the stator warming up, a broken wire opening due to thermal expansion, and then re connecting after it cools. BUT that usually takes a lot longer to happen, and a lot longer before it will restart.

It sounds more like it is running out of fuel, so it's either tank vent, or as Berger says the petcocks may have varnished up as well. And Taffy's recommendation will confirm whether or not it's running out of fuel.

So what's happening is that there is enough fuel delivery to fill the bowl up an start the bike, and enough fuel to keep it idling. But not enough fuel delivery to keep it going once you start flowing fuel through the main and up the needle jet.

Have you pulled the float bowl cap off to see if there is any crud in there?

Another easy test would be to pull your fuel line off where it connects to the carb and using a inline splice, hook up a piece of clear fuel line, and place the end in a gas can and turn on both fuel taps and see what happens, you should get a solid stream of fuel until the tank is empty. If you want to be sure that both taps are good, check them one at time to make sure they both are functioning well. This will verify you have good fuel delivery from the tank.

I am going to contradict myself here a little. There is a screen inside the carb above the float needle seat. It's made of a fine stainless steel mesh. If, for some reason this screen is varnished up, or has a bunch of crud on it, this too could be limiting fuel flow into your carb. With the carb off, and the float bowl off, you will see a phillips head screw that retains the float needle seat. Carefully remove the seat and you will find the screen on top of it. BEFORE YOU DO THIS, GET A NEW O RING FOR THE NEEDLE SEAT TO PUT ON BEFORE RE ASSEMBLY. These O rings have been known to go bad and start leaking causing a float bowl over fill and a constant dripping out the overflow tube.

Get back to us an let us know what you have found.

Also check your float level. Too low will do it.

I think you have problem with your filter or related to the air. If air can't be transfered then also this kind of problems happens. So basically you have to check all the connection related to the fuel tank to the engine. So you can solve the problem.

Guys,
Sorry to side track you here, but can someone explain the varnished up thing...and wehre it may be common I don't understand what you mean.

Cheers

Pilot

HI Pilot,

The varnish is what gets left behind when the gas evaporates over a long time. Since the carb bowl is vented to the atmosphere, the fuel is constantly evaporating slowly but surely. Some folks leave their gas on all the time to keep this from happening, but, that is fraught with it's own perils.

Additives like Stabilaid are supposed to keep this from happening. Best thing to do is to start your bike at least twice a month and warm it up fully, and you shouldn't have any issues.

Dale

Thanks Dale,
Makes sense, appreciate the explaination...and I learn a little more

Cheers

Pilot

Hi there, Pilot try replacing the spark plug cap, i had the same problem with my KTM took me 2 years to figure it out, I had the carb off 1,000,000 times, then noticed that the cap was tracking to the head once as i was trying to start my bike in the garage. this fixed the problem, and only cost $7.95 anoter tell tale was the idle was erratic up and down would even run on sometimes..

Help this helps.

Brett

Brett570.... I had a bloke with a Harley that had spent over $2200 (he showed me the receipts) with 2 different Harley shops trying to track down why his bike went soft after warming up and then giving it some shtick.
I couldn't get it to play up till the owner told me to give it a trashing...... then it would cut back onto one cylinder but when riding easy it was o.k.
Had to be spark i thought...... just solved a similar problem with my hot rod xr200 by testing the resister in the plug cap...... new cap and the xr roosted hard and reliable again.
Had a close look at the lead/cap on the Ugly Davidson to discover the conductor had not been trapped under the plug cap (was dangling down instead of being pressed under cap clip). threw a couple of 8mm silicon leads and caps on (had them in stock and it looked odd with just one blue lead) and she went as good as a stationary engine with wheels could go.
The owner didn't believe me it was a $25 fix. (thats when he showed me the receipts.... damn it) I got lots more work out of that one job as word spread.
goes to show its easy to overlook the simple things.

Yeah i hear you , stood there with matches and fuel a few times, but i thought im smarter than a lump of steel, took me a while abut i fixed it..

The pump probably sounded better on one cylinder anyhow, i hear they make great anchors..

Ah, so you've ridden one then!
I think they make better anchors than pump motors due to the cost of keeping them going........
To be fair tho, the newer models are certainly an improvment to ride....... they are only 10 years behind eveyone else now instead of 30.
Funny how something so slow can feel fast (could be all the tork or just that you cant slow them down enough at the end of the straight to get them round the corner).

Hmmmmmmmmmmmmmmm, I wonder the heck ever happened with the original poster? Makes a post, gets suggestions, and vanishes.

Great discussion though guys, the plug cap thing is actually in the maint sched if I"m not mistaken. I never had one go bad from a resistor point of view, just the old style that had you take the cap off the plug and the contact would ride on the threads, those don't last long. Once the newer bikes went to the metal cap on the plug, I never had to replace another one.

Great posts here about successes with plug cap replacements being the fix, especially after getting the bike hot.

Dale

Ah yeah sorry about that DaleEO. Got a bit off topic towards the end......
Seems as the heat and pressure increases it puts greater stress on electrical components an Mr spark keeps looking for the easiest path to ground. When I was a yunker a couple of crusty old racers said "throw those resisted caps in the bin son. They only cause trouble yaKnow" Seems the old buggers were right although it took several years before i had trouble with one...... then it took forever to figure it out coz I had forgotten about the old fullas advice by then and of course the symptoms only show under certain conditions.
Bikes aren't meant to have radios and plugs come resisted instead.
Never really had a problem with the caps that slip onto the threads, but I see wot you mean. Not much contact area and the threads would tend to eat into the cap.
Unrelated............. brilliant site this. there is always someone about. If Im on nightshift (330am here) all youse on the other side of the globe is awake and functioning. I can talk and listen bikes all day and night. Brilliant.

No worries Bergbro,

I was talking about the member who started this thread, cmags. Came in made a post wanting help and not a peep since. All of your, others suggestions were not necessarily off topic, all had the right intent, solving a problem.

And yes it's great, seems there's always some about on this site. It's nice now to have the "who's on line thing" back on the opening page, on some days there are quite a few logged on.

Dale

DaleEO said:

No worries Bergbro,

I was talking about the member who started this thread, cmags. Came in made a post wanting help and not a peep since.
Dale

Click to expand...

you're beginning to sound like me! that used to be one of my 'rants' years ago.

regards

Taffy

Taffy said:

DaleEO said:

No worries Bergbro,

I was talking about the member who started this thread, cmags. Came in made a post wanting help and not a peep since.
Dale

Click to expand...

you're beginning to sound like me! that used to be one of my 'rants' years ago.

regards

Taffy

Click to expand...

Yes I know...............The drive by's as I like to call them. At least do us the service of letting us know what happened. There have been many more, but, I have remained quiet.

It is all made worthwhile by the few grateful ones who get their problems solved, and are openly thankful.