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Chain break, now engine won't start


AndrewElvisFan
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Thanks for that. I was putting the poor starting down to needing a service and damp cold mornings. I'll try a new plug tomorrow and keep everything crossed!

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Page 4-44 in the manual is a good place to start and look at the diagram on 4-46. If it is the woodruf key it should be able to be fixed with the engine still in the frame and no changes to the timing.

Looks like I can't get away with trying to turn the flywheel through the inspection hole then :(
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Woah.

Just check the regular stuff first. If that key has bust, and the bevel has slipped AND the nut was loose maybe.

Bent valves. C'mon

That wont hurt the spark. Its an sr, they are as hard to kill as dt's. The clutch would slip and absorb the big shocks.

Try the plug and see what it does to the spark.

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I figured a £5 plug to start with! I'll stop stressing about the expense of the rest for now!!

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Woah.

Just check the regular stuff first. If that key has bust, and the bevel has slipped AND the nut was loose maybe.

Bent valves. C'mon

That wont hurt the spark. Its an sr, they are as hard to kill as dt's. The clutch would slip and absorb the big shocks.

Try the plug and see what it does to the spark.

Cynic

I agree any damage to the engine is unlikely and that they are hard to kill, but I would say from experience that the cdi units can and do fail, and the symptoms andrew describes, with the weak yellow spark, mimics one of my boys units' when it went tits up. Hopefully it is only a plug chop and this issue is a coincidence and bugger all to do with the chain wrapping itself around the front sprocket

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Not dissagreeing with the cdi, that is plausable. Ther rest? It is possible, just very unlikely.

I think its just bad timing.... bdoom tish...

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Gona throw this out there..if the ht cap is bad and is a resitor type then it need to be replaced. so for a few bucks 10-15 put a new ht cap and plug in it and see what that does for the spark.

People forget that the resistor in the cap can and do break down, and can back load the cdi causing them to fail.it s just a capasitor in the CDI and it when told to want's to dump it's load any restriction in it's abilty to do so will effect it's abilty,, resulting in a weak spark.

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Also a far easies way to check that the wood druf key is good and still in place without removing the flywheel is to set the motor at TDC thruogh the removable plugs in the cover and rotate the eng with a rod in the spark plug hole if it keep going up then it whack outa place.

Or put a timing light on it and crank the eng over.

Removing the fly wheel would be the last way I would check the timming for a bent key.

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New spark plug and getting really good blue spark. Just not firing :( Time to check the flywheel me thinks! Even tried half a dozen attempts at bumping in 2nd!

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Is the fuel getting through, the plug should be wet and smell of petrol, does it feel like it has compression and not easy to push in gear compared to before, thats if you bumped it before like.

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Yeah, fuel is getting through and I am in need of oxygen after attempting a bump start, just as before!!

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Before you go down that route, take the air filter pipe off the back of the carb, with a clean, dry plug, try and start it while spraying a little WD40 or Plusgas into the back of the carb. Do this with half throttle and no choke.

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Leave the plug out tonight, or if your brave enough heat the base with a blowtorch or such till its too hot to touch. Stick it in quick and kick with no choke.

With all the bumping it will be pretty well flooded out. Leave the plug out overnight if the above dont help.

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Thanks for that - ill try heating the plug first with a blow torch. Sounds the quickest thing to try and it's peeing it down now!!

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As soon as the boys are in bed I'll use jump leads with the neighbours car as all the attempts to start has drained the battery over yesterday and tonight. I'll keep you posted!

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