Vision just stopped

[Glyn]

My Vision has been getting daily use here in New Zealand. Rain or shine (mostly rain), in rush hour traffic, 20 miles each way to work it has never failed. Till last night, luckily only 1 mile from home. Filled it with gas at the station and it just would not start. 1 hour by the side of the road, plenty of sparks and fuel. Motor spins fine. Stator putting out 14 volts on the voltmeter. Have to trailer it back today. I'm thinking electrical? I also checked all the fuses and swopped out the ignitor box for a spare. Maybe the fuel pump is one the way out? I may lift the tank and put some neat gas down the bore to see if it will catch? Any ideas on this one anyone? Cheers Glyn.

[QBS]

Perhaps you bought some water at the gas station. Check it out first before going on to another possibility. Did you notice a refill tanker making a delivery while, or just  before, you pumped your gas? Your idea about pouring a little gas down a carb throat is excellent.

Fuel pump failures act like the bike is running out fuel. At anything more than a half a tank of gas, the engine operates as normal until half empty. After that, operation is erratic.

[Lucky]

Fuel pump failures act like the bike is running out fuel. At anything more than a half a tank of gas, the engine operates as normal until half empty. After that, operation is erratic.

which rules out fuel pump.

if it fires with a little gas down the throat then it's a fuel issue. use carb cleaner, dont pour in gas.

try jump or bump starting it. it might have enough juice to crank, but below 9.something volts the TCI won't fire...

try it again in a few hours, could it just be flooded?

check compression

[Glyn]

Thanks for that info. Got the bike back in the garage and no show with gas down the carbs. Took out and cleaned the plugs, they were a bit gunked up, but both give nice strong sparks.Unless the sensor for the timing has gone AWOL? not sure what else to try. Havn't measured compression but the bike was running real strong till it stopped so don't think it will be that. Always keep plenty of oil in it. All the other electrics are fine. It's a real mystery. I'm going to have to buy another bike this weekend to get to work on, since a daily commute in a car would be torture. Hope someone has an idea on this, I'm fresh out at the moment.
It was running so well too. Cheers Glyn. 

[SBVisionNZ]

Thanks for that info. Got the bike back in the garage and no show with gas down the carbs. Took out and cleaned the plugs, they were a bit gunked up, but both give nice strong sparks.Unless the sensor for the timing has gone AWOL? not sure what else to try. Havn't measured compression but the bike was running real strong till it stopped so don't think it will be that. Always keep plenty of oil in it. All the other electrics are fine. It's a real mystery. I'm going to have to buy another bike this weekend to get to work on, since a daily commute in a car would be torture. Hope someone has an idea on this, I'm fresh out at the moment.
It was running so well too. Cheers Glyn. 

Hi Glyn,
My experience with these includes the odd walk home but usually only after I've been playing with the carbs. They can be quite hard to get a response from even when putting gas straight down the throat. Just try twisting the throttle wide open a couple of times and then winding it over. You should at least get a few backfires through the carbs or pops out of the exhaust. Anything less and I'd be looking at the cranking voltage like Lucky suggests - presume you've tried jump starting from a well charged battery?
The other things to look at are the vacuum hoses to the Yucks box or the one to the fuel petcock - detached or holed hoses could give you loads of grief of the sort you describe.
If all else fails and you need a "new" 550 there's one for grabs on Trademe down Palmerston North way at the moment. Good luck Steve

[Lucky]

dont skip the basics, they'll get you every time. check the compression, you may have jumped timing.
it may crank strong because there's no/low compression...

[Glyn]

I think the timing may be the issue also Lucky. Is it possible that the timing can slip somehow? Even if it is giving good sparks at the plug?

[QBS]

Spark timing is fixed by the screwed on pick up coils.  It can't "slip".  The term "jumped timing" usually refers to cam timing changing because of cam chain and related sprockets changing their placements relative to each other.  Exceedingly rare and, as far as I know, unheard of regarding Vs.

Spark color should be blue and fat with a loud zap.

Two scenarios:
(A) Bike, with plugs installed, cranks but no start even with gas down carb...possible explanation:  Weak battery will crank bike but cranking voltage drops below TCI box function threshold=no start even in presence of fuel.

(B) Bike, with plugs out, cranks and shows "nice strong sparks"...Possible explanation: in the absence of compression related cranking resistance starter motor draws less amperage and therefore does not drop cranking voltage below TCI box function threshold=spark.

Suggest you use a known good spark plug and while grounding it against the engine, test for spark with spark plugs installed in the engine.  If no spark, jumper in a known fully charged battery and check for spark again....then please report back your findings.

[Glyn]

Yes the spare plugs both spark OK, even with another set of plugs installed. Perhaps I can jump it off a car battery? Will that be OK? I think that would be a good starting point.

[Lucky]

yes you can jump off a car battery, but NEVER with the car running.  the amperage from a cars charging system is much greater than the bikes & you will cook your R/R. resist the urge.

jumped timing means the chain has slipped, I have heard of Visions doing this.  you'll still get spark, but the valves will be out of time. poss bending one or all....

[Glyn]

Ta Lucky,

Well I hope not the latter. Mind you seeing that top cam doesn't seem that hard to remove I guess I can reset that, as long as no damage done. Will try the car battery today and report back.