Idle screw nightmare

[SeanMora77]

So I recently cleaned my Carbs and re-adjusted the floats"which were way off", and reassembled everything. Bike started and ran... Ok, but didn't want to idle at all. I checked the #1 carb idle screw and it was seated and as the Carbs were mounted I then checked the #4 carb and the idle screw was stripped. I tried to drill it out and sink a drywall screw in it to get it out but no such luck. Does anyone know a good technique for removing this? I am hoping it isn't ruined.

[BassCliff]

Hi,

Have you tried a left-handed drill bit?



Thank you for your indulgence,

BassCliff

[tkent02]

Exactly which screw are you talking about?

[BassCliff]

Hi,

Exactly which screw are you talking about?

I was assuming the "idle mixture" screw. But you know what kind of trouble I get into when I "assume".


Thank you for your indulgence,

BassCliff

[mrbill5491]

Sounds like you are talking about your sync screws(?) which there are 3 (1screw for #1 carb, 1screw for #2 and #3 and one for the #4 carb), so if you messed with those, your snyc is all screw up. And if you are talking about the screws on top front part of the carb those are you idle mixture settings. There is only one idle screw for all the carbs and its the big sucker underneath with a knurled knob in the middle.

[BassCliff]

Hi,

Sounds like you are talking about your sync screws(?) which there are 3 (1screw for #1 carb, 1screw for #2 and #3 and one for the #4 carb), ....

To clarify, with the CV carbs, the #3 carb is the "master" carb and has no vacuum sync adjustment. You synchronize #1, #2, and #4 to #3.



The vacuum adjust screw between #1 and #2 (above) will adjust the butterfly valve in #1.

The vacuum adjust screw between #2 and #3 will adjust the butterfly valve in #2.



The vacuum adjust screw between #3 and #4 (above) will adjust the butterfly valve in #4. There is no adjustment for #3.

More information here:

Synchronize Carburetors
(With the Morgan Carbtune)



Thank you for your indulgence,

BassCliff

[SeanMora77]

Idle mixture screws, sorry im a newb , but yes, the screw on the top front of each carb. These are used carbs, not original, and new to me. I have since removed the carbs from the bike and found that the #3 carb idle mixture screw is stripped as well, though i havent come near it with my drill. To clarify, its not the threads that are stripped, but the flathead slot... there is nothing there to get a bite on. #1 and #2 are fine, I can back them all the way out. I've read and hopefully did not misunderstand that these screws should be backed out 2 turns from lightly seated. As I found them, #1 and #2 were seated, not backed out at all. Im 90% sure these are Mikuni BS32 carbs, there are pics on my profile. Thanks

[MisterCinders]

If the slot is stripped, is the top of the screw exposed enough to dremel a new one?

Otherwise, you may need to slowly drill with a left-handed bit until it bites to back the screw out. DO NOT USE AN EZ-OUT. Seriously, those things suck and will break, ruining your carb, destroying your manhood, and crushing your soul.

[Steve]

To clarify, its not the threads that are stripped, but the flathead slot... there is nothing there to get a bite on.

If the slot is stripped, is the top of the screw exposed enough to dremel a new one?

They are buried rather far down, but there is an easy way to do it with a Dremel and a cut-off wheel.

Just cut a slot in the tower, making sure you are as close to the middle as possible.

Both of these carbs have been slotted for screw removal.



.

[SeanMora77]

No sir, the screw is far too deep to dremel a new slot. I'll try the left hand drill bit method... Would applying heat help at all?

[hjfisk]

No sir, the screw is far too deep to dremel a new slot. I'll try the left hand drill bit method... Would applying heat help at all?

Did you look at Steves post, when you dremal it you will have to slot the tower to get to the screw , but no worries it has been done many times and it works, I would stay away from them with a drill, odds are with the drill you'll be looking for another carb. Look at the pics Steve posted it will work

[SeanMora77]

Thanks for posting that Steve, looks like the best solution considering my resources. I'll post results as soon as I get a chance. One more question, does anyone know where I can find a replacement idle mixture screw should I need one?

[Steve]

There is a good chance yours might be re-useable, but send me your address, I will send you a screw (or two, if you need them).

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[koolaid_kid]

There is a good chance yours might be re-useable, but send me your address, I will send you a screw (or two, if you need them).

.

Wow, one to two free screws from Steve. You should be honored.

[Steve]

Wow, one to two free screws from Steve. You should be honored.

Would you be any more amused if I said "screw you"?

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