Author Topic: A10 Noisy and running rough  (Read 489 times)

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johnjag

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Re: A10 Noisy and running rough
« Reply #15 on: 10 July, 2019, 17:34:34 »
Hi - sounds to me like a weak mixture, something like the pilot screw adjustment or a blocked pilot jet. What carb are you running? If it is a Concentric the pilot jet is actually a bush which is difficult to unblock. You have to drill through the other side and unblock with a piece of wire (crude I know) and then tap the drilled hole and screw in another shortened pilot screw to block the hole.
John.

Marka10

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Re: A10 Noisy and running rough
« Reply #16 on: 10 July, 2019, 19:43:01 »
Hi John

Thanks for your input,

I now think the original Problem is the petrol mixture. To satisfy myself and increase my knowledge I am going to set valve timing, valve gaps and ignition timing.

I will than know all this is correct and try running again.

I was thinking the mixture is to rich and not all the petrol is burnt on ignition stroke and because electronic ignition fires on exhaust stroke, on each piston (sacrificial spark)  I am getting firing on the exhaust stroke.

Cheers

Mark


Mike Farmer

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Re: A10 Noisy and running rough
« Reply #17 on: 11 July, 2019, 10:38:09 »
 :) :)

Maybe something as simple as loose manifold nut/s

Mike 8) 8) 8)

chaz

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Re: A10 Noisy and running rough
« Reply #18 on: 11 July, 2019, 16:02:50 »
seems to me there is a lot of people suffering fuel problems, common fault misfiring and poor running. we straightaway assume the bike has a problem despite our regular tinkering,makes me wonder if its down to the fuel. As ethanol has been widely discussed over the last few years its dropped back off the radar recently.
a couple of my Brits have problems, the Jap stuff gets used more often and fuel turned over but I see many carbs that have corroded brass parts while overwintering.
as some have problems with fuel evaporating (tufnol spacer discussion) , modern fuel is upto 15% ethanol which absorbs water, this could be vapourising. also I go back to the days of open fuel storage tanks, working in a garage and common to find pinking as droplets of water banging around in the combustion chamber not being burnt off.

would be interesting to use a octane booster additive or maybe try a tankful of Avgas same as we used to use on racetracks until the ACU deemed racers had to use pump fuel.

Mike Farmer

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Re: A10 Noisy and running rough
« Reply #19 on: 11 July, 2019, 16:58:09 »
 :) :)

Back in the day I used a lot of 100/115 AVGAS (occasionally 115/130). On the road A65. But Avgas now is straight 100LL  IE 100 octane low lead--no Heptane content. So I doubt that the new stuff would be much of an improvement. I have no idea what the "funny" content is.

Mike 8) 8) 8)

Marka10

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Re: A10 Noisy and running rough
« Reply #20 on: 11 July, 2019, 17:04:00 »
Hi
Thank you for your inputs, can anyone recommend a additive to try.

Thank you

Mark

chaz

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Re: A10 Noisy and running rough
« Reply #21 on: 11 July, 2019, 17:26:45 »
I have Silkolene ProBoost in the unit, bought for a friend who drives rally cars but outlawed before he bought it...
https://www.silkolene.com/motorcycle/fuel-additives/pro-boost/

TTJOHN

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Re: A10 Noisy and running rough
« Reply #22 on: 13 July, 2019, 21:07:25 »
Sounds like air leak to me, if it's popping and banging, this did happen to me once , bike running fine then started playing up when I checked I could get a feeler gauge between the manifold.