Pilot screws

[Slavvy]

I've dicked around with the pilot screws on my carbs trying to resolve an unrelated issue. Now I'm trying to restore them to how theyre supposed to be set and having difficulty, hoping some of the wise men here can help :)

The internet tells me that they need to be wound out 1.5 turns from the stops for my carbs, but this isn't working, the throttle still needs to be spun about a quarter of the way until it wakes up. Which way do i take the screws to increase the 'response'? Would I wind them in to reduce the amount flowing through, or wind them out? Motorbike carbs are almost a complete mystery to me.

The bike starts fine and idles reasonably well, makes power, doesn't stutter etc and everything else seems to be set correctly and working properly. And no, it isn't the throttle cable adjustment :p

[imdying]

They need to be balanced against each other. Motion Pro sell a basic manometer. Any bike shop in NZ can get one for you. They're about $100 IIRC. If you google about, you'll find instructions for making your own out of some plastic tubing.

[willytheekid]

:laugh:
I've dicked around with the pilot screws on my carbs trying to resolve an unrelated issue. Now I'm trying to restore them to how theyre supposed to be set and having difficulty, hoping some of the wise men here can help :)

The internet tells me that they need to be wound out 1.5 turns from the stops for my carbs, but this isn't working, the throttle still needs to be spun about a quarter of the way until it wakes up. Which way do i take the screws to increase the 'response'? Would I wind them in to reduce the amount flowing through, or wind them out? Motorbike carbs are almost a complete mystery to me.

The bike starts fine and idles reasonably well, makes power, doesn't stutter etc and everything else seems to be set correctly and working properly. And no, it isn't the throttle cable adjustment :p

:blink:Dosn't sound like the pilot screws are your problem....they only control the off-throttle running of the carb - such as idle & deacceleration.
To set by ear is easy, just have the bike idle at 1200 rpm (or slightly higher than normal). then as you adjust the screws the highest idle point/RPM is usually close to bang on.
Next check the revs drop cleanly and don't "hang" & then drop(to lean), or the revs drop below below idle and then rise again (to rich).
Screw OUT to richen (More fuel @ idle) and Screw IN to lean (Less fuel @ idle).
But I would be checking for blocked jets, sticking floatbowls etc.

Good tip- To lean=Burnt valve seats!$$$, To rich=soot build up but less chance of damage to the engine.....Hence I recommend setting it slightly rich :)

If you have troubles, first google the carb settings and details (as every carb is different in its settings etc) If you can't figure it out....go to a shop or you may well cause some damage or simply burst into flames as you tootle down the road :laugh:

-and as for the manometer (not nessacery if you have a good ear...but great for piece of mind & accuracy)
http://www.kiwibiker.co.nz/forums/showthread.php/141943-How-to-make-a-manometer-(carb-balancing-tool)-for-under-10

(I have finger adjustable Pilot screws on my FCR's to allow me to change the fuel ratio depending on the conditions , Hot day, cold day etc)

OHH--- "trying to resolve an unrelated issue"...what was that?

[imdying]

Hence I recommend setting it slightly rich :)What's wrong with setting them correctly, if you're going to be in there changing it anyway.

[willytheekid]

What's wrong with setting them correctly, if you're going to be in there changing it anyway.

True...but I ride a guzzi :laugh: only two valves per head, so slightly rich is the safer option.-(was just thinking safe side tuning for a carb learner...hate to read their valves burnt due to to lean settings)
-But you are quite correct (as usual!:bleh:) setting the perfect ratio would be great!

[imdying]

It was a genuine question. Is the Guzzi air cooled? (I assume it's carbed?) May be good advice on air cooled bikes?

[Slavvy]

:laugh:

:blink:Dosn't sound like the pilot screws are your problem....they only control the off-throttle running of the carb - such as idle & deacceleration.
To set by ear is easy, just have the bike idle at 1200 rpm (or slightly higher than normal). then as you adjust the screws the highest idle point/RPM is usually close to bang on.
Next check the revs drop cleanly and don't "hang" & then drop(to lean), or the revs drop below below idle and then rise again (to rich).
Screw OUT to richen (More fuel @ idle) and Screw IN to lean (Less fuel @ idle).
But I would be checking for blocked jets, sticking floatbowls etc.

Good tip- To lean=Burnt valve seats!$$$, To rich=soot build up but less chance of damage to the engine.....Hence I recommend setting it slightly rich :)

If you have troubles, first google the carb settings and details (as every carb is different in its settings etc) If you can't figure it out....go to a shop or you may well cause some damage or simply burst into flames as you tootle down the road :laugh:

-and as for the manometer (not nessacery if you have a good ear...but great for piece of mind & accuracy)
http://www.kiwibiker.co.nz/forums/showthread.php/141943-How-to-make-a-manometer-(carb-balancing-tool)-for-under-10

(I have finger adjustable Pilot screws on my FCR's to allow me to change the fuel ratio depending on the conditions , Hot day, cold day etc)

OHH--- "trying to resolve an unrelated issue"...what was that?

This is all excellent advice and exactly what I was looking for, thank you. That link is to my post though, sharpen up :p

The 'unrelated issue' turned out to be a misfire because of dodgy ignition coil wiring :facepalm:

[bogan]

This is all excellent advice and exactly what I was looking for, thank you. That link is to my post though, sharpen up :p

The 'unrelated issue' turned out to be a misfire because of dodgy ignition coil wiring :facepalm:

+1 to the advice already given, Factory Pro specify the same procedure, and they are fucking onto it for all things carbed :yes:

[willytheekid]

That link is to my post though, sharpen up :p


:blink:.....:facepalm:...Its either my age or all the head injuries over the years :laugh: