reving

[James Atkins]

When trying to turn down the revs on my roadster , do I have to do both carbs.
Its running about 12000 when hot

[Geoff Edwards]

Hi James,

Yes, you need to adjust both carbs and balance them. You don't say the year of your MGB - hope it is not revving at 12,000!!

Geoff

[Dave Linkson]

It won't rev to 12,000 rpm! It's not an F1engine, think you mean 1200 rpm. Try adjusting the idle screws, (tickover) one on each carb only very slightly mind, and each one exactly the same amount, just a gnats...
There's a John Twist video on youtube that will show you how to do it, but your carbs may differ slightly if they're HS4s, where the mixture adjustment screws are on the bottom of the carbs and screw up or down to adjust.. He's adjusting HIF carbs..

[James Atkins]

Thank you both, Will book it in at mg summit in maidenhead as I don't want to muck it up and then have moor trouble

James