S.U Carb jetting
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S.U Carb jetting
I'm about to strip and clean the S.U's on my Interpol .The bike is running "OK" but as it's running through Commando "peashooter" pipes which are pretty much straight through and taking into consideration the poor quality of the fuel these days would anyone recommend any changes (main jet sizes etc) ?? . Cheers .
Re: S.U Carb jetting
SU's aren't a carb full of jets. Just one which is almost always a 0.8". To change fuelling is a case of changing needles, a real minefield ! Stick to the stuff in there and see how it runs once the idle mixture is correctly set.
Acceleration and top revs can be affected by changes to the spring and damper oil, but if you're really keen to have it metering exactly right, book a rolling road session.
Regards, Terry.
Acceleration and top revs can be affected by changes to the spring and damper oil, but if you're really keen to have it metering exactly right, book a rolling road session.
Regards, Terry.
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Re: S.U Carb jetting
Spoke to a bloke about a rolling road session .He said it could be difficult to get accurate readings due to the posifeed two stroke system on the rotary engine !!
Re: S.U Carb jetting
How odd !
Maybe someone who has had a rotary dyno'd will care to comment ?
I set mine with an old air/fuel meter, works fine.
Maybe someone who has had a rotary dyno'd will care to comment ?
I set mine with an old air/fuel meter, works fine.
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Re: S.U Carb jetting
How come the "Peashooter" pipes havn't melted ,and how many "Burn Marks" on your biker boots ,J.B.
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Re: S.U Carb jetting
They are stainless steel and a lovely colour from straw brown tapering away to polished stainless at the reverse cone end .The colour is exactly the same both sides so I guess the rotors mixture/balance is good. .A sort of external/visual colour tune !!!!!
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Re: S.U Carb jetting
I'm so glad it's not just me!('cos the colour of the exhaust pipes is how I check my Carb's:Mixture& Balance )
Someone did try to explain to me once why this method can't be used with Fuel Injection,and why (with F/Inj:) the exhausts never get that lovely pale grey almost white colour after a couple of hundred mile's motorway blast ,J.B.
Someone did try to explain to me once why this method can't be used with Fuel Injection,and why (with F/Inj:) the exhausts never get that lovely pale grey almost white colour after a couple of hundred mile's motorway blast ,J.B.