Somethings not right

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bikemonkey
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Somethings not right

Post by bikemonkey »

Whilst riding home from work today, and thankfully on the last mile of my journey, the NC decided to have a hissy fit.

It was suddenly down on power, wouldn't idle, sounded like shit and stank of I think petrol.

I managed to limp it the rest of the way home and when I stopped outside my house it just cut out like I thought it would.

It then struggled to start, sounding like one or more cylinders wouldn't fire. I got it running but it still sounded like shit and wouldn't rev properly.

I'm thinking plugs/leads/coils. I'll get a video posted up tomorrow after work.

Any ideas?
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Davez29
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Re: Somethings not right

Post by Davez29 »

Sounds like fuel starvation, vacumn in pipes or tank or even lack of fuel. But im no expert :)
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bikemonkey
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Re: Somethings not right

Post by bikemonkey »

You think so?

I had only just topped the tank up just after I left work.

Tank to carb line isn't that old, and neither is the vacuum hose. Plus I replaced the tank breather last year.

Another thing to make sure of though, but wouldn't explain the distinct strong smell of petrol when the bike was running.
dobbslc
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Re: Somethings not right

Post by dobbslc »

Crap in carbs after the fill up causing flooding?
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bikemonkey
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Re: Somethings not right

Post by bikemonkey »

Very possible, I haven't really checked the condition of my tank, ever.
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Davez29
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Re: Somethings not right

Post by Davez29 »

The only time i get a strong smell of petrol is when i have a lack of it, just as its going onto its last gasps of trying to find some in a empty tank. Can you lift your fuel cap easly when it happens, do you hear a "pop" when it does open? Again dont want to throw you, just some of the things i would be looking at, easiest first.
ireson75
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Re: Somethings not right

Post by ireson75 »

Crap in carbs for definite, sounds like familiar symptoms. The float bowls will be full of shit!
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Re: Somethings not right

Post by dobbslc »

If it's flooded badly you might need new plugs too.
It'll be some crap jamming the fuel valve open probably.
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bikemonkey
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Re: Somethings not right

Post by bikemonkey »

Hmm, no crap in carbs.

There was petrol sitting in the back two carb rubbers when I pulled the carbs off so I only looked at the back two carbs which were clean as a whistle as you can see here:

Image

Image

After that I pulled the plugs and they were quite wet, so I cleaned them up on the hob and got them really hot. After they'd cooled I spark tested them earthing against the frame and they sparked alright but loads of petrol shot out of the rear right cylinder.

Shoved it all back together to see if it'd run on that cylinder and I don't think it did. Here's a video.

http://s1126.photobucket.com/user/olive ... 1.mp4.html


I think it's time to try new plugs, and I don't have any spares. Might swap the front with the back tomorrow see if that works, if so then I'll be buying new ones. If not, then something else is afoot....
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bikemonkey
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Re: Somethings not right

Post by bikemonkey »

The video isn't very clear if I'm honest, but it sounded like a bag of spanners, wouldn't idle properly and the exhaust stank of petrol.

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