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Motorcycle Discussions => British Bikes => Topic started by: raptorkev on July 31, 2011, 02:34:53 PM

Title: pilot jet
Post by: raptorkev on July 31, 2011, 02:34:53 PM

hi all what size is the pilot jet in the mk1 amal 30mm

Title: Re: pilot jet
Post by: Rex on July 31, 2011, 05:31:59 PM

They used to be 25s, but now they're an unremoveable bush inside the carb, and apparently the size doesn't matter... ;)

Title: Re: pilot jet
Post by: rogerwilko on July 31, 2011, 08:56:59 PM

I will not respond to that....wait a minute.. i just did!!

Title: Re: pilot jet
Post by: chaterlea25 on August 01, 2011, 05:23:04 PM

Hi,
The answer is, "Too Small"
its about 0.015 in. dia
And yes it does matter >:(

HTH
John

Title: Re: pilot jet
Post by: davidg on August 02, 2011, 01:48:17 AM

its .014" and you can clean it carfully with a number 78 drill through the air adjuster screw hole.

Title: Re: pilot jet
Post by: phil_h on August 10, 2011, 10:05:03 PM

I recommend you drill out the bush and fit a 30 pilot.
With modern 10% ethanol fuel you need another 5% by volume compared to old fuel so all old jetting tables are now wrong.
And what's the biggest prob with amals ... they run weak pilot circuits very quickly because of wear in the crap alloy !
I know the calcs are marginal, but I'd rather have a slightly rich pilot to aid starting and idling myself !
I'm converting all my fleet to run richer pilot circuits.

Title: Re: pilot jet
Post by: toz on August 11, 2011, 10:55:16 AM

Gave mine a bit of a poke out last week, the improvement in the smoothness of the running and tickover has been amazing. Engine runs a lot cooler too it seems,It may have been slightly blocked and running too lean.