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I need your advice on valve clearence please. I have 2L engine, C&B 11 mm cams, DellOrto 40 DHLA carbs. What is the best set of valve clearance for C&B 11 mm cams for street riding?
I read on BB that with higher cams the valves should be set a bit tighter according to shop manual specs.
I guess 0,48 mm for exhaust and 0,43 mm for intake. What is your opinion ? May I go safety to 0,45 mm for exhaust and 0,45 mm for intake not to ruin the valves ?
Janusz
 

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Assuming you haven't got the box (it's written on the label...)

Inlet 0.5mm

Exhaust 0.55mm

These are for the AR 109 280S (10.9, commonly rounded up to 11mm)
 

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Discussion Starter #3
Assuming you haven't got the box (it's written on the label...)

Inlet 0.5mm

Exhaust 0.55mm

These are for the AR 109 280S (10.9, commonly rounded up to 11mm)

That is correct with C&B catalog for 280/280 deg duration cam. Problem is that PO said that cam is 290 deg intake at 0,45 mm and 284 deg exhaust at 0,475 mm. No code on the cams and no other evidence what exactly the com is. He call the cams CB47 whatever it meens.
Are they the same cams as AR 109 280S ?
Janusz
 

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Not sure if what you have is the same as what we have but we also sell the 292S (12mm lift) C&B cams and they recommend the same clearances for those as the 280S so I'd go with that. Too tight and the valves will remain slightly open when the engine's hot.
 
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