pz carb DQ

steve baker

Moderator
I recently bought 20 -- .602" carb gauges and only one of them was exactly .602"
The others were either above or below .602"
I'm in the process of making my own gauges.
Stay tuned!
The poor quality of tech gauges has been a problem for many many years. When you buy a new gauge first check is to measure the gauge. This sport needs a quality gauge manufacturer! Haven't seen one yet for karting!
 

fatboy1dh

Member
It's my belief that everyone should have that carb gauge in their tool box and measure their carb frequently to make sure it passes tech.
Doesn't this go against everything you preach about the LO206 being a "just bolt it on and go" kind of engine? If a gauge set (and ability to use it) is required to run this engine, you can rule out a large portion of the current guys running it.
 

Jimbo

A trial w/o witnesses is like racin w/o tech
fatboy1dh
Not at all!!!

Thank you for your skepticism. No offense taken and i hope i can say the following without offending you.
Your post gives me an opportunity to expand on my post and bring attention to some of the great things that the 206 has to offer.
First of all things on any engine change over time. We would all be very naive to think otherwise.
If you are telling me that nothing on your clone engine, your Yamaha or shifter kart engine never changes that would be the epitome of naivete.
I'll bet all kinds of things change on them and a lot quicker than it does on a LO 206
300 karts at the CKNA finals at New Castle 2 weeks ago. Not one engine failure!!
I did hear one guy bitchin because his idle jet was too big and it failed tech. I also heard him say he uses a piece of wire to clean it with.

Learning to us a no go gauge is not rocket science.
Briggs even has a video on how to do this and many other things as well.
Here is the carb tech video.
In addition, If you would like to attend a live tech seminar i plan on having one next spring for the racers from the local track.
I will not be the presenter. It will be someone with much better credentials than mine.

I plan to meet with someone to discuss making the .602 carb gauge tomorrow.
I will also tell you that once i have them available each and every one of them will be measured before it goes out the door.
 

CarlsonMotorsports

Premium User
Jimbo,
While I agree with you -- read the text on the screen shot you showed -- that is the same wording as the tech manual.
This needs clarification. I brought it up to Dave previously, but it needs mentioned again.

Specifically:
"no-go can't pass into slide area"

Pass into?
Now, either something passes through, or it enters into....I've never fully understood this phrase in tech "pass into."
I interpret that phrase as ENTER into (as do most tech men I know.)
However, some tech guys and competitors want to claim that this phrase means that the no go can't "pass through" or "fall into."
The tech book wording is not good in this instance. I think that some know what Dave meant, but it's being interpreted differently in the field according to how that local tech guy wants, and that creates a lot of the problems that I've heard of at least.

Bobby can make the gauges for you, no doubt. Will they be available through Briggs though -- that would be best for all. If we're going to have an "official" set of tech tools, then let's have them subcontract it out and make the tools available through their vast distributor network, right?

Just my thoughts anyhow.
 

CarlsonMotorsports

Premium User
FWIW, Lewis Stout sponsors a series of tech seminars for many different engine packages used in karting currently.
I am fortunate enough to lead the tech seminars on the LO206 classes @ The Southeastern Karting Expo in Sevierville, TN & the OVKA Swap Meet & Trade Show in Wilmington, OH (both in February this year.)

If anyone has an interest in attending these tech classes, you can get in contact with Lewis directly.
Stout Racing Engines
Lewis Stout (423) 584-6663 Email: gummy07@charter.net.
 

Jimbo

A trial w/o witnesses is like racin w/o tech
Brian
I think there is a better way to do this very important tech measurement.
Once i have the prototype tool i will make it available for Klaus etc to review.

I'm not sure i understand what your are confused about.
To me "pass into and Enter mean the same thing"

If my method and tool is accepted then the video probably should be redone or and addendum made.
That's not my call. None of this is.
Again this is just my opinion.
 

jjchat

Member
I read the rule as the tool may not enter the slide area. I conduct the tech procedure by removing the carburator off the engine and place the carburetor intake side down on the bench. With a slide in the carb, I insert the tool until it stops. I then move the slide up and down with me finger while gently holding the tool in an upright position. If the slide is able to move the tool, I make the ruling that the tool is entering the slide area.
 

steve baker

Moderator
I read the rule as the tool may not enter the slide area. I conduct the tech procedure by removing the carburator off the engine and place the carburetor intake side down on the bench. With a slide in the carb, I insert the tool until it stops. I then move the slide up and down with me finger while gently holding the tool in an upright position. If the slide is able to move the tool, I make the ruling that the tool is entering the slide area.
Thats the way WKA use to do it at National races.
 

Jimbo

A trial w/o witnesses is like racin w/o tech
Yep, guaranteed 100% fool proof method. No skill or judgment involved right? NOT
 

fatboy1dh

Member
fatboy1dh
Not at all!!!

Thank you for your skepticism. No offense taken and i hope i can say the following without offending you.
None taken and none intended from me either. I am just playing devil’s advocate here, as I own a karting business and a set of tech tools.

I agree with your concern over the tech and legality of parts. This year alone, I have had a 2019 brand new stock carb thrown out for the very thing you very well known animal experts are discussing. I’ve also had the needle fail tech. While I firmly believe the tech guy messed up my carb bore measurement, my needle did fail the gauge. IMO, I shouldn’t have to check these things on a brand new motor. Either Briggs needs to tighten up their production or these expensive gauges we buy need better quality. Thank god it was my personal engine and not one of my customers’
 

Jimbo

A trial w/o witnesses is like racin w/o tech
We do tons of 206 engines (brand new and well used)
We not only do the ones we sell but also ones people have bought from other sources.
In fact i like to do ones from other sources since that gives me the opportunity to see what comes out of other shops.
I will say that i very rarely see something that has been "intentionally done to cheat"
I will also say that i have NEVER seen a new carb fail the 602 measurement. I'm not saying that's not possible though.

If you had a new carb fail i'm very suspicious that the test was done wrong. That further verifies what i am saying about improving the tool and actual test procedure.
 
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CarlsonMotorsports

Premium User
Yep, guaranteed 100% fool proof method. No skill or judgment involved right? NOT
And if the head of the bolt which holds the actual measurement part (T-bar) of the no-go gauge hits the slide, is that considered illegal?
I've heard of this occurring before.
I've taken the bolts out of my gauges and machined the heads down slightly so as to not ever have this become an issue in the tech barn.
FWIW, I've got 3 - .602 no-go gauges and 2 are spot on, the other is slightly over (1/2 thou. or less.) All were checked with recently certified 1" mics. I guess I'm giving the competitors the benefit of the doubt on size. LOL
 

Jimbo

A trial w/o witnesses is like racin w/o tech
Brian
The ones i just sent back had the entire head of the bolt sticking out past the end of the tool.
 

jjchat

Member
And if the head of the bolt which holds the actual measurement part (T-bar) of the no-go gauge hits the slide, is that considered illegal?
My gauge has the bolt recessed. If there is a bolt head past the gauge, I would argue that is not a dq. I have cheked my 602 gauge several times and it is almost .0005 over. I have heard of new ones coming out that are under and have an allen head sticking out from the gauge. So it is worth having the tech person double check their gauge as well as explain how they are making their ruling. In the instances in which I have made a DQ for this, I have shown people the rule, shown them the gauge, demonstrated the procedure several times for them so they can see the repeatability of the process.

I have also yet to see a new carb in which the gauge even begins to go past the narrow point let alone come close to or enter the slide area.
 

steve baker

Moderator
None of these gauges should even be leaving the manufacturer without being first validated for accuracy! ( This has been a major problem for many many years )In the industry, gauge tools are measured with a gauge that is 10 times more accurate than the gauge itself. For these engine tools the manufacturer should be measuring them with gauges that are accurate to .0001 inches! Furthermore the organization that owns the tech manual should define that exact gauge design and size dimension!

IMO, the .602 gauge should be manufactured and precisely measured to be .6022 inches.

Steve
 
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CarlsonMotorsports

Premium User
My gauge has the bolt recessed. If there is a bolt head past the gauge, I would argue that is not a dq. I have cheked my 602 gauge several times and it is almost .0005 over. I have heard of new ones coming out that are under and have an allen head sticking out from the gauge. So it is worth having the tech person double check their gauge as well as explain how they are making their ruling. In the instances in which I have made a DQ for this, I have shown people the rule, shown them the gauge, demonstrated the procedure several times for them so they can see the repeatability of the process.

I have also yet to see a new carb in which the gauge even begins to go past the narrow point let alone come close to or enter the slide area.


That's the way it should be -- the way I tech, and the way I teach.
 

Jimbo

A trial w/o witnesses is like racin w/o tech
For starters the ones i am making will be one piece. No bolt and they will be right on .602"
 

steve baker

Moderator
For starters the ones i am making will be one piece. No bolt and they will be right on .602"
Making your gauge exactly right on the allowable spec ( in this case .602 ) is dangerous in the tech barn!
Its general knowledge and accepted to use no go gauges with a small tolerance on the + side. The preferred method is to have the organizations / tech manual owners to specify the exact dimensions for the gauges to be used. Tech gauges need to be accurate, uniform and consistent for all series and at all race tracks thru out the country for any given engine platform.................. however in karting this is not the case, unfortunately!

BTW ............interesting this spec in Briggs rule set says ------- Venturi Measurement Horizontal Min:0.602 Tool: A20 ! ....................typo error.


Steve
 
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Jimbo

A trial w/o witnesses is like racin w/o tech
Steve
As always, thank you for the advise.
No offense but i'm making them for the racer.
Actually having the gauge slightly under the specified size will help the racer make sure his carb is legal.
If a 601" or a .6015" gauge goes through then the carb is definitely illegal.
If tech people want them that's great but that's not my focus.
 
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