No Straight Away Speed in Spec Class

We run some toe out on the stand so there will be zero toe loaded.
 
Kstrycharz07 said:
Toe was set with a laser toe gauge with me in the kart, It is set to 0. The series offical has been racing forever and he always tells me "Caster will kill a low HP motor"

Could ride height make a big difference??

Replying to Al, the motors are sealed so I cannot check degree of cams or change valves. I could try jetting more but I am already running rich, whenever I pull the plug it is black. I am using a AR3910X. Valve lash, I have not checked, but I recently got the crank, rod, and piston, and rings replaced. I ran fully synthetic oil not knowing better and ruined the crank and rod.

I have looked a lot of places about Carb setup but I really have no idea where to go. We run Ruiking carbs and the only modification is that they are jetted. We need to run a marked carb by the series organizer so the only thing I could legally change is the jet size.
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If the plug is black, you're already too rich, put a smaller jet in it. Is one jet size, say from .038" to .039" is a 5% plus change. If you go to a smaller jet, and it goes lean, put a larger low-speed jet in it. Total fuel flow will not increase as much doing that as it would if you put a bigger high speed jet.
 
Kstrycharz07 said:
I am the quickets guy in the corners pulling 1-2 kart lengths after turn out I just have no acceleration or top end.
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There's your problem all other things being equal.
Though you may be gaining a couple of kart lengths after turn out, they transitioned to acceleration and going straight or straighter before you did.
Your still turning and scrubbing off speed while your gaining on them and when you get straightened out and able to move on to acceleration they are long gone having started their straight acceleration long before you.
You can even hit the exact same apex as the other karts but when you hit it you are in a situation where you still need to reduce speed to complete the turn. If you don't then I suspect your also prone to get a little loose when the others do not.

Sure you need to hit your apex and sure you can make your apex earlier or later the same as others do.
But your line, speed and how and where you do your needed deceleration to get thru the turn before and after the apex will not be the same.

Try thinking about it this way: Pick and think about any place in any turn you encounter at the track your racing. Now think about the line between any two places or points along the turn. ... ok?
Now think if it will be faster to negotiate between the two points you picked at an averaged >constant< higher speed or (as i'm suggesting your doing) will it be faster to negotiate between the two points while decelerating from and averaged lower fast to exit speed where you can start accelerating again?
What i'm suggesting/IMHO factually is you can set a better exit point or area on the track by reducing the amount of time you spend in the turn decelerating. In fact/IMHO by controlling where you reduce your speed appropriately you can cause a portion of the turn(arc)to be taken at a then slightly higher speed. From the start of the portion of the turn i'm suggesting(arc) because your turning with grip already sent to the outside tires you can accelerate and maintain a slightly higher averaged speed between the points. The secondary benefit of what i'm suggesting is it will also place you at a better or more easily chosen exit point.
Most sprint only racers kart or road course motorcycle racers cann0t come to understand the above because they cannot comprehend the need to control deceleration for any reason other than hitting their chosen apex.

or not ... cause this is all IMHO and ain't necessairly right anyway! ... :)

Is it brake, turn, accelerate. Or might it be insert and use an arc to create a higher average speed between two points by thinking brake, insert arc, turn, accelerate? nawwwwww or maybe I finely presented my hard to understand concept in an ok way? proly not ... :)
 
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I see you behind kart lengths "charging" into the corner gaining on them and then loosing what you gained during or after exit.

Your skill are there and ok because if not you'd be constantly off course in or after each corner, charging into it.
I think I'm trying to describe something which occurs when drivers take heed to the old saying of "Go slower to go faster".

Would you say your more towards man handling it thru corners or more towards relaxed and on autopilot thru corners?

... i'll not give my guess on an answer. ... :)
 
As told to me by Paul Kistler 410 sprint car engine builder via challenge of how to fix his number one problem.

His number one problem he can't fix is degraded engine recovery when the track slows what's being raced because of high grip in turns and the horse jockey still keeps his right foot to the floor.

I'm thinking you also may have the same problem keeping your engine from being able to git goin as well as others.

Just thinking on what you offered and trying to help, not anger you.

by the way the answer I offered was driver education about his problem and how to manage it on the track
 
found this for you at: https://www.eccarburetors.com/169F-43-Main-Jet-for-Ruixing-Carburetors-Choose-Size_p_1548.html




169F-43 Main Jet for Ruixing Carburetors (Choose Size)
This jet is for the Ruixing clone carburetors. Not guaranteed to fit other clone carburetors. If you are using the Tillotson PK clone carburetors they will use a different main jet.

For Most Engines Running Gas Main Jets range from .034-.038

If you are tuning your carburetor and it starts to break-up and crackle it’s lean add more main jet. Or if goes flat on top-end this could be lean and/or your cam can no longer make power at the rpm you are tuning.

If the engine hits a wall on the top end, acting like you hit the kit switch and bogs its rich go down on the main jet.

There can also be other reasons for carburetor tuning problems from ignition coils failing, coil gap being set incorrectly or fuel system problems such as fuel tank not venting or fuel pump failing or not effiecent enough to race engines. Before you start tuning make sure you don’t have another issue.
 
Put one degree of toe in and a little more caster and you'll go faster on the straight if you hold the wheel steady. Also check your wheel base left to right. Racing karts since 1973.

Sundog
 
sundog said:
Put one degree of toe in and a little more caster and you'll go faster on the straight if you hold the wheel steady. Also check your wheel base left to right. Racing karts since 1973.

Sundog
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What am I looking for exactly when measuring my wheel base?
 
Check to make sure you have full throttle? That the pedal isn't coming up to the stop before its all the way open? Brake disc spinning free ?
 
This - ' Also check your wheel base left to right.'

You would be surprised how much a chassis will 'crab'. It may not seem like much, but it all adds up. And it's free speed.
 
Chris Cooper said:
This - ' Also check your wheel base left to right.'

You would be surprised how much a chassis will 'crab'. It may not seem like much, but it all adds up. And it's free speed.
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What do you mean by crab? do I want my front/rear wheelbases to be identical? Currently I have a wider rear then the front.
 
Wheelbase is front-to-rear
Track width is width of centerlines
Make sure your front axle (kingpin to kingpin) is parallel to your rear axle.
 
Corner exit speed, work on getting the kart to roll the corner more freely. Entrance and exit. Your straight speed is dependent on corner exit speed.
 
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