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Engine Failure while riding.

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Bike's still giving me the middle finger after a top end rebuild and camshaft replacement. I've ruled out the decompression system as the culprit but am now back to square one with one big clue. It's something in the crankcase.... joy. Got a video of it doing it's thing as well. Sounds alright when it's putting around, but when you get on the throttle things start clacking around and the moment you pull in the clutch and allow the motor to spin freely it dies. Engine failure happens at 1:25 in the video and dies again at the end but no clacking that time.

 

If anyone has an idea of where to start, or a specific part to start with please let me know. I'm in way over my head here.

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Sounds to me like your idle speed is a bit low,, wind it up a couple of hundred revs and see what happens?

   Have had a 600 which would idle real low, but also a 650 which could not cope with too low idle and would flame-out at stops, very frustrating.

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This sounds like the engine is running out of gas. Ride the bike with the gas cap loose or until it dies. Immediately turn the gas off. Get a long thin screw driver and open the float bowl drain screw. This is on the left side of the carb. Anything come out?

 

BTW... Are you sending me the OE cam?

Edited by mcma111
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2 hours ago, mcma111 said:

This sounds like the engine is running out of gas. Ride the bike with the gas cap loose or until it dies. Immediately turn the gas off. Get a long thin screw driver and open the float bowl drain screw. This is on the left side of the carb. Anything come out?

 

BTW... Are you sending me the OE cam?

Yes I am, just got everything back together today and wanted to make sure it would start before I shipped off the stock. It's packaged up sitting on the lift at the moment and I'll send it out monday morning.

I upped the idle and checked the gas when it cut out and there was gas in the float bowl. I'll go through my petcock, and clean my carb again tomorrow as well as an oil change and keep trying. Killed my battery trying to start it earlier and it just reminded me to invest in a kickstart.

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if you sit and idle and rev it right up does it still die ?

sounds like its not getting enough fuel - petcock partially blocked - float height

other than that the bike sounds good  :thumbsup:

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Check your CDI connections and clean them, if it still die's on you, have the CDI checked, it may be time to replace it, also check & clean your kickstand sensor positioner, good luck

Edited by Mike Moto
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Cleaned the carb again today, and noticed some incomplete "Dave's Mod" work. Added the 0.02" thick washer to the bottom of the needle and removed the airbox snorkel. Cleaned out the petcock and replaced some vacuum hoses. I can't hear anymore clanks or mechanical rattle coming from the engine now which I don't understand but enjoy. Idles good and revs good and doesn't die out either during the rev or post rev back to idle. Gonna change the oil, check the filter for metal pieces and test drive it later today. 

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Well it seems to be enjoying the care I've given it. No mechanical clunks, no dying out and no new abnormal issues. :) Oil was super black and the filter seemed really clogged. 

There was some metal shavings, really fine stuff, in the filter and filter port. Didn't seem to be magnetic so my guess is aluminium. Noticed on my left side where the cam bearing sits there was a sharp edges on the outside; guessing the top end was rebuilt previously but was not lubricated with moly paste so there was some grinding. It concerns me a bit but not super majorly, not enough to replace the top end. 

Seems to be back in business, fingers crossed.

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Sharp edge where the came bearings sit is OE machining from the factory.

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