What size idle jets do people run in their webers.

Im currently running 50's on my 44IDF's but seem to block them regularly enough.

I've been running 55's in mine with the standard 36mm vents, but am playing around with vents and jetting at the moment so that might change.

I don't know that idle jet size has much to do with how often they block up though - I run a pretty serious filter, and have only had them one jet partially block up so far in a shade over 2000km (ironically it was a loose fiber from the filter - go figure)

You need to run whatever size it "best lean" at 1 1/2 - 2 1/2 ish turns out on the mixture screws

That said i use to run mine with 45's in there.
You reckon yours use to clag up!

Next time i would try whatever gave me a best lean at 1/2 a turn out because yes - they clog up WAY to often for me


That all said - i run a 52 in my Pict
Why doesnt that clog up.

I reckon it has more to do with carb design than idle jet size

next opinion please..........................

ha - I may fit another filter above the gear box then. I have one on the suction side of the pump, maybe one o discharge would be good too.

When their blocked, does it spit and carry on when just idling? Or usually a little higher in the revs, round 1500-1800rpm.

a blocked idle jet makes it run lumpy.
More than likely there will be a fibre stuck in the hole that makes the fuel dribble or blocked.
Whatever - it wont spray.

When you get above say 1500-ish the motor will pull strong as the mains cut in

Yeah - what bizarre says - at idle it's very obviously running on 3, but when the main's cut in at that 1500-2500 mark it just irons out.

Most obvious is that it's REALLY easy to bog it when first starting moving.

yeh, seems to pull around 2300-2500. Boggy on take off, quite annoying.

Hard to tell for me as i haven't had it working properly long enough to know what 'normal' is, to know what isn't lumpy at idle

http://www.aircooled.net/gnrlsite/resource/articles/jetting.htm

re the clogging i had 45s in the 40s on my 1776 and yer as barry said the clog faster than u can blink

but i found the secret after i cleaned my tank out was to run a metal bosch EFI filter
latest one i put in was for a mazda bravo
and the other main place dirt comes from is the air cleaners
make sure u have good elements and no leaks

One trick I've learnt is you can usually diagnose which jet it is that's blocked by removing the plug leads from the dizzy cap one at a time - when you pull the lead on the cylinder with the blocked jet, the engine idle basically won't change since that cylinder wasn't firing in the first place.

Also means if you find that each plug lead has the same effect on the idle that you're probably not chasing a blocked jet.