Scura died at speed ... why? Why? WHY?!!!

[slowkitty]

Hiya all ...

 

My 02' Scura has a tendency to cut its engine mid-ride. After about 5 times over the last 100 km or so; the sequence is usually like this ...

 

1. High speed (usually after 45 mph)

2. Fast deceleration with brakes (not engine braking)

3. Pull in the clutch

4. Engine quits

5. Panic

6. Continue clutch in position, contiinue in whatever gear (bike is rolling), push starter and bike fires

7. Continue as though nothing happens

 

It does not happen all the time, sometimes no problem at all. Pretty hap-hazard fashion ... First time it happened I was lane splitting and probably gave the 2-stroke bike behind me a heart attack cos' I freaked out and not release the brakes when the bike died. Now i know better.

 

What gives? Similar experience?

 

Cheers

 

Cat

[pasotibbs]

I would start with checking all electrical connections first as a failure here is most likely to give the symptoms you describe (the side stand switch would be my first suspect), if it only occurs during heavy braking then it could be movement of loose battery terminals or water in a switch or relay ?

 

If all normal fault finding fails try to find a quiet road and make the fault appear, if you can make it happen on demand then you could attach a test light to find which circuit is failing,for instance it could be just the supply to the fuel pump or ECU rather than the entire ignition circuit that goes dead (it may be that if the ignition circuit goes dead someone watching from behind will see the brake light go off ?)

 

good luck

[dlaing]

I have had that happen and it was fixed by a tune up.

(adjust valves, then TPS, then balance TBs)

I think the "cause" was an exhaust valve being too tight.

[Paul Minnaert]

so what idle rpm do you have? Before you find your solution, turn it up to 1200. That will save your heart.

[Tom M]

I could be wrong, but the way I'm reading this is the Scura stalled when the clutch was pulled in while decellerating?

 

If so it doesn't sound like an electrical malfunction to me. I'm with Dave and Paul on this. I'd go with a fresh set of gapped spark plugs and verify the 1200rpm idle to start, then move on to the full tune up if that doesn't fix it.

[Reboot]

May be all wet here, but simple thing to check 1st. You say under hard deceleration? I would check your side stand interlock switch to be sure is isn't the culprit if it only happens on occasion and under hard braking. Have heard of instances where this has caused a similar condition. Try bypassing the switch and see if it still happens.

[pasotibbs]

I could be wrong, but the way I'm reading this is the Scura stalled when the clutch was pulled in while decellerating?

 

If so it doesn't sound like an electrical malfunction to me. I'm with Dave and Paul on this. I'd go with a fresh set of gapped spark plugs and verify the 1200rpm idle to start, then move on to the full tune up if that doesn't fix it.

 

I was thinking from his description that as it only occurs in very heavy braking that it was "g force related"

but it could be it's just stalling due to being badly setup as you say, it just seems weird for the fire to go out on both pots (maybe the flints are wet )

[slowkitty]

Idling is low, less than 1000, in fact, even in ambient temperature of about 27 degrees celcius, I need to hold the throttle manually until the bike warms, otherwise the engine will die. However, with a warmed-up bike it's not a problem.

 

Will try out a higher idling.

 

Cheers

 

Cat

[docc]

Single cylinder (thumpers) do this commonly. Known as 'flame out' you can expect it to go away with a good tune and proper idle.

[st. augustine]

definately experienced the same thing when those damn yellow lights in the sky say the green light is changing to red! Why do they have red lights anyways....can anyone explain that? Definately solved this inconvenience by adjusting the valves.

 

Hey, don't we ride for the exhiliration?

 

the st.