Carb No Go question

[DynoDon]

Careful Don. How many times has it been said by you and countless others, "if it doesn't say you can, then you cant"? While I don't subscribe to this point of view and have been berated on here for my views many times, MANY folks have been DQed with the statement, "the rules don't say you can". If that statement is going to be held as a "truth" (as silly as I think that is) then what's good for the goose is good for the gander. The rules must hold true for ALL of us. Tech and competitors alike. JMO

I think, and it is only my opinion, that what you are describing may be taken out of context. I always looked at that statement " if it doesn't say you can" as observation of spirit and intent. For a tech to apply the spirit and intent, he needs to know this engine inside and out. As for a tech to have 'ALL' TOOLS AVAILABLE to him for tech, I personally agree that if the tech is for big races he should have them. That means a bunch of money spent. But for the little tech that is doing a local race event, To spend the large amount of money it takes to purchase all the tools would break him. If tech would require every one to have it all, then there would be many tracks that would be without tech. Then where would the sport be? I have several pin gauges and no go gauges of different length and diameters that I had certified by the local machine shop. I calibrate my tooling depending on the size of the spec required to those items if a question comes up. I always add .0005 to the measuring instrument. If I find something that is out of spec, I recalibrate my tooling to double check for accuracy. I will also take the time to call another individual in for them to determine if we are on the same page. If I have a third person, I will use him as well. Checks, double checks and verification is the way to make a call that is in question. If the item is still in question, it needs to be sent to AKRA for the final answer. Unless you are absolutely positive that the item is wrong, I do not suggest calling it wrong. JMO

 

[Competitive Karting]

I didn't state that a dial caliper was not appropriate for use in tech .... that is my instrument of choice for cursory measurement in tech. However if a situation arises where a measurement must be verified to determine legality, I revert to a micrometer and gauge block for final determination.




NO-GOs are generally +.00015 to +.00025 of the specified size.


Jim Stone
AKRA Steering Committee
AKRA Southeast Region Representative

Ok I have another question. I have a .615 pin gauge and I put the pin gauge into the carb and it does not go through and you cannot see light around the pin gauge but it does try to support the pin gauge. Would this be in your view illegal? I have been racing since 1994 in karts and I was always told the if the No Go pass though it was illegal. So I am trying to under stand how when a rule is written stating that the Ventrui max size is .615 and the tech tool enters both sides but does not pass through to me the ventrui is below the .615. The rule does not state that and I understand the plate check because it is a stamped hole but the carb is tapered (funneled down in the back of the carb and funneled out the front of the carb)

 

[Renegade]

Asking the same question several times and hashing the same argument multiple times will not in this case result in a different answer. Two well known techs have explained the definition of no-go and Stony even referenced direct quotes from the rule book. Despite what you have always been told a no-go is exactly that, a no-go. If it goes even slightly or tries to enter to a point that it self supports then the part is wrong. As to your question if the Venturi max size is .615 and the no-go is .615 then the no-go will not enter. They would be the same size and at the same temperature there would have to be excessive force applied to push one into the other. As for the taper yes it is there but the no-go is only to be used to check from the choke side of the carb. This is where the air enters and the check is to prevent funneling this area.

 

[Competitive Karting]

Asking the same question several times and hashing the same argument multiple times will not in this case result in a different answer. Two well known techs have explained the definition of no-go and Stony even referenced direct quotes from the rule book. Despite what you have always been told a no-go is exactly that, a no-go. If it goes even slightly or tries to enter to a point that it self supports then the part is wrong. As to your question if the Venturi max size is .615 and the no-go is .615 then the no-go will not enter. They would be the same size and at the same temperature there would have to be excessive force applied to push one into the other. As for the taper yes it is there but the no-go is only to be used to check from the choke side of the carb. This is where the air enters and the check is to prevent funneling this area.

I understand what you are saying but I have some that I received that were suppose to be perfect CNC .615 carbs and my tool goes in and when I checked my No Go when it was cold it was below the .615 then I checked them today and they are checking fine. I just do not want to put them on and get DQed. I guess I will just send them back to be on the safe side.

 

[Renegade]

Metal grows and shrinks with temperature, you want them at max for the most power. The trade off is under certain circumstances you can be wrong, the only solution is to play it safe and give up a little power.

 

[rebsfan4]

I understand what you are saying but I have some that I received that were suppose to be perfect CNC .615 carbs and my tool goes in and when I checked my No Go when it was cold it was below the .615 then I checked them today and they are checking fine. I just do not want to put them on and get DQed. I guess I will just send them back to be on the safe side.

SECTION 6- 4 Cycle Engines: General Requirements And Inspection Procedures

2nd Paragraph: Last sentence

"The competitor has the right to request a reasonable time period to allow for cooling to ambient temperature prior to inspection"

 

[Dover Power]

I didn't read every sentence,, But I didn't see anywhere that you should not rock the no go while checking any part that requires a no go to check..

Indeed seen many no go gauge that's tapered on the leading edge..
Also the area in question (venturi) is also tapered.. Rocking the carb or gauge can cause a FALSE reading.. Face it the racer,,builder or person tearing the motor down in tech has to be his own lawyer... Is it being teched correctly,, procedure,, tools and raw knowledge.. We are not in the 80's anymore.. Theirs classes being offered,, endless info on the internet & DVD's... Education is around if you look..
JD

 

[Renegade]

A tech rocking a no-go either has no idea what they are doing, or they are deliberately looking to toss you. Rocking a gauge is a huge no no.

 

[Kart43]

It can never be as simple as NO GO it requires careful visual inspection also, you can make a very oval venturi that the NO GO will Not enter, therefore the NO GO gauge is only the beginning.

 

[M.D.racing]

Maybe it should be no go thru. I understand all that is being said. To me go means thru. No Go. Not No Start. Y'all can wear me out. I don't mind. Just a view point.

 

[M.D.racing]

But on the other side of things, a piece of paper's thickness is. 004". That. 004" would keep you plenty safe and if you think that makes a measurable difference in power, then I got the ocean front property..........

 

[Renegade]

If you allow it to start people will take advantage and do some real creative things with that venturi.

 

[Renegade]

But on the other side of things, a piece of paper's thickness is. 004". That. 004" would keep you plenty safe and if you think that makes a measurable difference in power, then I got the ocean front property..........

If you figure the increase in area and circumference of a circle that .004" represents you better believe it will make a difference. close to 3 tenths on peak and even more on top end.

A .615" carb is: Area = 0.29706 circumference = 1.93208

A .611" carb is: Area = 0.29321 Circumference = 1.91951

 

[rebsfan4]

People always trying to make things complicated.

Nowhere EVER has a NO-GO gauge been able to start......EVER!!!

I'll be real blunt about this......IF you are of the opiniin that it SHOULD be allowed to start and simply not PASS-THROUGH (Which is a completely different thing), then I'll just say you are looking for ways to cheat the rules. PERIOD.

 

[Competitive Karting]

People always trying to make things complicated.

Nowhere EVER has a NO-GO gauge been able to start......EVER!!!

I'll be real blunt about this......IF you are of the opiniin that it SHOULD be allowed to start and simply not PASS-THROUGH (Which is a completely different thing), then I'll just say you are looking for ways to cheat the rules. PERIOD.

But when there are tech tools out there that are tapered they could enter

 

[rebsfan4]

None of my No-go gauges I have enter. Might want to shop around. Buying a tool that has taper doesn't make it allowable to build carb to said tool. Responsibility lies with builder.