new carbs questions

alan hodge · May 19, 2021

from burlen

Dear Mr Hodge,

Changing the position of the needle does not affect the pilot circuit. The taper on the bottom of the needle controls the transition from the Needle Jet to the Main Jet. I’ve attached one of our tuning leaflets which explains the different circuits in the carburetter.

The 1 ½ position is merely a starting point from which to tune the carburetter. If your bike runs well with the Pilot air Screw at ½ turn out it is not a problem, simply the setting that cylinder requires.

Kind Regards

Phil Beresford
Customer Services Advisor

Fast Eddie · May 19, 2021

Call that problem solved then?

Now move on to the next...!

Bernhard · May 19, 2021

Stating that Half a turn out is what your engine requires is being a litte bit economical.
The pilot jet can also have some effect on small throttle operation - you may have to compensate by other means...........

Fast Eddie · May 19, 2021

Bernhard said:
Stating that Half a turn out is what your engine requires is being a litte bit economical.
The pilot jet can also have some effect on small throttle operation - you may have to compensate by other means...........

I think so too. But the reason they’ve said that is because the pilot jet (Bush) in the carbs in question is not adjustable. So, it’s the best compromise.

alan hodge · May 19, 2021

MAP air filter came today looks good went on fairly easily will take bike out tomorrow for road te4st

Craig · May 19, 2021

Hope it smooth sailing tomorrow Alan ! Enjoy your ride !

alan hodge · May 23, 2021

just took 30 miles ride MAP air filter pilot air screws out around 3/4 turn needle clip in middle slot ran on country roads around 50mph with 2 miles final at 55mph then turned off key and coasted down my street to garage bike ran perfectly plugs NGK BPR7EIX chocolate colored and i am going to leave well enuff alone (ordered some autolite AP63s so might try them just for the hell of it)

Tornado · May 23, 2021

alan hodge said:
NGK BPR7EIX chocolate colored and i am going to leave well enuff alone (ordered some autolite AP63s so might try them just for the hell of it)

Great to hear you've sorted it (despite the contradiction in your last sentence ;-) )

alan hodge · May 23, 2021

are we ever, really, once and for all, done tinkering with our bikes? my wife calls me Tinker Boy

lazyeye6 · May 23, 2021

At least she doesn't call you Tinker Bell

Craig · May 23, 2021

Sounds like fun Alan ! we locked down or up until 9 June … and no never finish tinkering or fettling I think they say over there …. Not sure plug type in mine right now will let you know as they seem real good , previously ran NGK bp7es , have tried lots of different brands over the yrs , current set are iridium I think , been in 2 or 3 yrs now ….

alan hodge · May 23, 2021

craig our NC Goobernator Roy Cooper turned us 'loose' from covid restrictions about two weeks ago i got both shots so can go anywhere mask free except nursery schools or doctor offices.......what an ordeal it's been!
hang in thar

Schwany · May 24, 2021

alan hodge said:
craig our NC Goobernator Roy Cooper turned us 'loose' from covid restrictions about two weeks ago i got both shots so can go anywhere mask free except nursery schools or doctor offices.......what an ordeal it's been!
hang in thar

Nice to be let out of your cages. Sure wish that was happening here.

If you see a light at the end of the tunnel in the Seattle area, it's the CDC pulling the governor on a leash coming to tell you to put your mask back on.

The AP63 Autolite plugs should work as well as what you are using now.

Schwany · May 25, 2021

Schwany said:
Nice to be let out of your cages. Sure wish that was happening here.

If you see a light at the end of the tunnel in the Seattle area, it's the CDC pulling the governor on a leash coming to tell you to put your mask back on.

The AP63 Autolite plugs should work as well as what you are using now.

I tried a set of APP3923 Autolite plugs today. They are the same heat range as the AP63 Autolite plugs. Difference is they use a 5/8th wrench and are double platinum. They work fine with my big carburetors and EI. I don't have carburetor or spark plug color issues though, so probably doesn't mean a thing. Just letting you know you shouldn't worry about not using the popularly recommended plugs.

Hopefully I haven't confused anyone. lol

alan hodge · Jun 18, 2021

plug color update just got back from ride set air screws at 7/8 turn out put in new autolite AP63 plugs did plug chop after riding a few miles at 50mph color is the golden tan holy grail i have been looking for far and wide bike starts first kick runs great problem solved at last

Craig · Jun 18, 2021

What I like to hear , good for you Alan , proof ,keeping at a problem can payoff , great news ! Enjoy …

alan hodge · Jun 18, 2021

thankee craig meant to add i put one of those dual K&N type air filters on as well bike runs like it has another gear 3rd is as fast as 4th used to be feels happy too

Schwany · Jun 23, 2021

alan hodge said:
plug color update just got back from ride set air screws at 7/8 turn out put in new autolite AP63 plugs did plug chop after riding a few miles at 50mph color is the golden tan holy grail i have been looking for far and wide bike starts first kick runs great problem solved at last

Good for you.

I told you AutoLite plugs worked. I was not guessing. I currently run the APP3923's, and in my case could probably go to a colder plug with an APP3922. I was running the APP5224 which have a slightly longer reach. They worked fine, but I wanted to try a colder plug. My plugs use a 5/8ths plug wrench. The AP63 you are using is equivalent to the APP3923 heat range, but yours is the 13/16th wrench version and not a double platinum.

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