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CARB slide lift holes drilled?

Mercer

Mercer

Guest
Guest
Am starting this as a new thread.
Am trying to go back to a stock carb and airbox on a C10 from pods and jet kit as noted in other posts.

Now noticed the slide lift holes have been enlarged as well.

Question: Do I go back to stock slides without drilled holes as part of return to stock C10 configuration?
Or can I go back to stock jets, etc and leave drilled hole slides in carbs as is?

The reason I question this is slides are broke in and worn to specific carb body. I am cautious about
changing slides from one body to another.

Of note in researching drilled hole slide theory and practice on net.........
Opened up a can of worms there! Talk about controversial topic!

As I do not have a clear path here yet. Any opinions greatly appreciated.
Thanks.
 

This above is what was in C10 as purchased. Ran more than fine just 33 mpg no matter the twist of the wrist.

1. Seems after more net research I can fill and redrill slides to stock. That to answer as one possible solution.

2. The other might be leave slides as drilled and see what happens with the return to stock jetting in combination,

3. Lastly could pull slides from another rack.

This I believe to be least likely as any slides are matched to carb bodies by wear patterns no matter how minute.


At moment as slides may be pulled in situ am inclined to toss the dice and see what happens with #2 option.

If anyone here has been here before would so like to hear about it! Noticed on net thumper riders have varying opinions on subject.

Oh yeah. After all a C10 is just 4 little thumpers singing in unison..............Ha ha!
 
Interesting question. I don't know what to say about the holes drilled in the slides.
Steve in Florida would be most knowledgeable on this subject.
About interchanging the slides, unless there is some damage or wear you can
swap the slide without worry.
 
rwulf said:
Interesting question. I don't know what to say about the holes drilled in the slides.
Steve in Florida would be most knowledgeable on this subject.
About interchanging the slides, unless there is some damage or wear you can
swap the slide without worry.
Click to expand...
Of course I have an opinon on the subject. However I've been told that when I weigh in on a subject, it suppresses other folks from wanting to chime in. So I've been waiting for the conversation to take it''s usual internet twists and turns before I interject my thoughts.
 
Steve in sunny Fla said:
Of course I have an opinon on the subject. However I've been told that when I weigh in on a subject, it suppresses other folks from wanting to chime in. So I've been waiting for the conversation to take it''s usual internet twists and turns before I interject my thoughts.
Click to expand...
Well Steve,
Been on net researching this holey subject. Not counting you there are zillions of opinions on this subject. A good many claiming exactly the opposite of each other as to how these damn holes actually work, HA!

Believe it or not I personally try not to bother you unless you volunteer to chime in.

But since you are the resident C10 expert and seems this subject before our group has not elicited what you or I would have expected please do jump in. You have stated you are not a jet kit or pod fan. I am trying to get back to airbox and stock jets. You have been most helpful in that endeavor so far. Now I have found enlarged hole in slides! Oh &h!t, glad I was paying attention.

So have three questions specific of you if I may.

1. Will in your opinion there be any upside/downside to leaving enlarged hole used with stock jets otherwise on a C10?
2. If detrimental in fact, can I use stock slides from my spare carb rack? That rack shows wear patterns for it's slides. Minor but present.
I am reluctant to do this as I have never mixed slides from one carb body with another in any rack. Let alone one rack to another.
Always figured they were mated by their wear patterns slide to carb body however minor. I was a Norton nut in past life!
3. If can not use extra slides due to wear patterns, can I close and redrill holes to stock on my current enlarged hole slides? I have a drill press.

As I am poised to return carbs to bike. Am only now waiting for any advice as to above hole issue at hand.

If you do chose to interject your thoughts I for one will be most thankful.
 
Take a deep breath. you're complicating something that's not complicated.

Drilling the slide hole only does one thing, it makes the slide more reactive when lifting and dropping. That's it. Actually you are in the enviable position of having slides that are drilled and some that aren't. Replacing the slides is easy with the carbs on the bike. EASY. So just go ahead and assemble the carbs with one matching set, and at some time in the future if you want to see what the "other" set feels like, drop them in. All that worry about "worn in" is just that... worry. Slides can get a lot of wear, and they can not want to respond well because they kind of "stick" in the position they've worn into. A set of slides with different wear won't be so susceptible.

And it's not brain surgery, it's just carbs. Nobody is gonna die over the choices you make regarding which slides you run. Trying both sets is the best way to learn. It's really a great opportunity, with no downside. Fly Mercer, free yourself of the bonds of convention and experiment. It is the spice of life!

Steve
 
He he !Thanks Steve!

Since my last post measured all C10 slides with calipers. They are not precision parts as some brands are. All fit quite loosely in their respective bores, By design would assume as are sealed at top by the diaphragm. Believe with that measure answered all my questions. And yes your confirmation is the flying papers!

A Norton Amal carb would cease to idle or tune with that much play. All my carb experience has been with non CV carbs. Did put Mikunis on one of the Nortons. Got rid of the CVs on my Virago too. Live and learn.

You are so right, a C10 is a great opportunity to experiment. Sure hope after this experiment I can find better than 33 MPG.
 
rwulf said:
Interesting question. I don't know what to say about the holes drilled in the slides.
Steve in Florida would be most knowledgeable on this subject.
About interchanging the slides, unless there is some damage or wear you can
swap the slide without worry.
Click to expand...
Well you and Steve saved me countless worry on slide issue!. That is what I luv about COG. Someone has always been there before on a C10!
 
I just saw this.
My thought was; the larger holes allow the slide to move a bit quicker.
{Steve sed the same thing, only better}

The reason I'm posting now is; The carbs I bought (with drilled holes) "also" had lighter/weaker return springs.
ie; Check yours to see what you have...

Ride safe, Ted
 
Last edited:
connie_rider said:
I just saw this.
My thought was; the larger holes allow the slide to move a bit quicker.
{Steve sed the same thing, only better}

The reason I'm posting now is; The carbs I bought with drilled holes "also" had lighter/weaker return springs.
ie; Check yours to see what you have...

Ride safe, Ted
Click to expand...
So did you leave them or toss them? My springs seem same in length and compression. Just .125 hole in slides.
 
I'm not running them.
But, it's not because of the slides....
ie; The Carbs I bought are off of a ZX-1000 and are 36 {or 38 ??) mm carbs.
I opted to stay with the OEM 32 mm carbs. {They have Steve's 2 Minute Jet kit, and overflow pipes}

Ride safe, Ted
 
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