Track Tac

Small gear vs. regular gear

hummmm...

Actually, I'd like to try it from up high with a lot of timing lights checking when the weight passed.

I think Al's suggestion was to wrap a string around a RR with a weight on it and time it from release to a point on down.
I don't think he ever thought about dropping the weight from high up to maybe find different rates of acceleration along the way.
 
My god call Sheldon Cooper, we've got string theory involved 😅 if chain tension isn't perfectly the same between experiments the out come will differ, hell in that case a guy with a looser chain will be faster due to the centrifugal force of the chain pulling on the tips of the teeth
 
Paul has a viable idea . The other change i see needed is . The location of the weight shoud be on the primary sprocket . In this case a setup with a jackshaft .
You could change drivers , adjust the chain , use the jackshafts pully for the power/weight drive .
Digatron / mychron with jackshaft sensor or mph mounted on the axle .
 
95 shaw said:
When we are limited by design, the effects of ratio is fairly constant. However, gear bound is still a possibility.

Use of a quick change with different initial ratio can change the output range.

GM's crate engines has taught me that gear bound can be overcome by carb choices, and thoughts on how to use the available power.
Dyno sheets only tell the story if used exactly as described by the torque curve.
There are ways to use this otherwise with a distinct advantage.

Follow the leader, or monkey see, monkey do, nets the same result, following the same guy, especially since you have no idea why what you are doing works at all.

Karting alone does not have these problems.
Just more options to overcome the same issues.
Click to expand...
Hasn't the 602, 604 classes gotten crazy?
 
rupp76 said:
My god call Sheldon Cooper, we've got string theory involved 😅 if chain tension isn't perfectly the same between experiments the out come will differ, hell in that case a guy with a looser chain will be faster due to the centrifugal force of the chain pulling on the tips of the teeth
Click to expand...
Looser 👍
A little tight becomes a lot tight by the end of the race
 
jaymancds said:
Al, this is mathematically true, but similar to your "theory" on calculating stagger, they will not be the same in practice. They will act differently as they are different, and the torque associated with them will be different.
Click to expand...
It appears to me that you're getting your forces all confused. For instance, "torque" is a static force. Think of a torque wrench, applying 10 foot-pounds of divorce to a bolt. Nothing is moving right? If you could connect your rear axle to a foot-long torque wrench, you could run the engine at full throttle and measure the torque at the axle. The axle would not be moving so you could not calculate the horsepower. No horsepower can be calculated until something starts moving.

My demonstration of ratios is absolutely correct. Your contention that the different size sprockets might perform differently, in a real world situation, may, or may not, be true, and I tend to agree with you.
 
flattop1 said:
Paul has a viable idea . The other change i see needed is . The location of the weight shoud be on the primary sprocket . In this case a setup with a jackshaft .
You could change drivers , adjust the chain , use the jackshafts pully for the power/weight drive .
Digatron / mychron with jackshaft sensor or mph mounted on the axle .
Click to expand...
Actually i think if both weighted pullys were the same diameter .
Would a 4-1 weight difference provide a viable test ?
 
We run predator red plate and decided to try mini gears and we put the same exact gear on we were running with big gears and we lost our speed. What adjustments should be made to the ratio when switching to mini gears?
 
Kevin.74 said:
We run predator red plate and decided to try mini gears and we put the same exact gear on we were running with big gears and we lost our speed. What adjustments should be made to the ratio when switching to mini gears?
Click to expand...
I'd assume you're running a big momentum track. In that case it's not made a difference on mine, tracks where you keep it pinned the whole race. Where it's helped mine is paper clip style corners where there's a brief roll off the throttle on entry. Or small bull rings like indoor. That's where it has helped us.
 
LDR said:
I'd assume you're running a big momentum track. In that case it's not made a difference on mine, tracks where you keep it pinned the whole race. Where it's helped mine is paper clip style corners where there's a brief roll off the throttle on entry. Or small bull rings like indoor. That's where it has helped us.
Click to expand...
We just started using Minis this year and found the complete opposite, odd how that works... For the smaller on/off tracks, have not found the sweet spot for minis thus generally run regular gear set. For the big momentum tracks, minis produce more speed and really help in qualifying. I think everyone is going to have a different take on this but its atleast what we've found. Mind you, we are running blue plate clone Jr 3.
 
Kevin.74 said:
We run predator red plate and decided to try mini gears and we put the same exact gear on we were running with big gears and we lost our speed. What adjustments should be made to the ratio when switching to mini gears?
Click to expand...
What standard gearset did you run, and what mini gear set are you running?
With a red plate Predator, it will be hard to see the advantages, but can be there if understand how to utilize the mini gear system.
 
The mini gears simply allow you to hit those "in between" ratios that are not really easy to get with your standard 15/16/17 tooth driver. They also allow you to use a smaller gear on both your clutch and axle which is less rotating mass, miniscule but if you're chasing a tenth or so and your setup and tires are mostly on point can make a difference.

They also allow the use of a shorter chain, (again less rotational mass) as well as the ability to move the engine back further on the rail for better weight balance (per PMI/Slack)
 
1fasttiller said:
The mini gears simply allow you to hit those "in between" ratios that are not really easy to get with your standard 15/16/17 tooth driver. They also allow you to use a smaller gear on both your clutch and axle which is less rotating mass, miniscule but if you're chasing a tenth or so and your setup and tires are mostly on point can make a difference.

They also allow the use of a shorter chain, (again less rotational mass) as well as the ability to move the engine back further on the rail for better weight balance (per PMI/Slack)
Click to expand...
ok that sound beneficial in every situation. so why are some people claiming it doesn't work for this motor or that class. this doesn't address how it should be an advantage (utilize the mini gear) in different situations.
 
I think some are over thinking the whole mini gear system….. this is what I do…… I have led lights programmed on my mychron5 on our tight corner 1/8mile I am shooting for 64-6500 off the corner. Hoping I don’t stop pulling but 10ft before I get into the corner where we have quite a bit of a rpm drop….. if I’m maxed out halfway down the straight and I’m either feeling the motor not pulling anymore or the kart in front of me is pulling away, I am dropping the rear gear…… it should not change much of the initial rpm off the corner that I shoot for….. this track is long straights tight corner…. The smaller system is intended to get you up to speed faster. It works quite well on tracks such as this. If I’m on a 10/50 and another racer is on a 12/60 and we mark off 25ft, we accelerate at the same time I am going to beat the racer with the 12/60 after 25ft…..

Hope that helps some…. It’s what I use and it helps a ton…..

Also to add I don’t care what my max rpm is. I could be 6900-7300…..
 
Last edited:
J'-remy said:
i'd love an explanation on how to utilize the mini gear system. and no i'm not being a Smart A. i sincerely want to understand what the science behind the claims
Click to expand...
Utilizing the gear system is knowing how and understanding what gear to use to maximize your speed. What to look for in RPM, how to read a Mychron helps with the mini gears, how to select a ratio. Knowing that what matters is the corner exit RPM and not as much end of straight RPM.
I never said the mini gear system will make your kart faster, in any post over the yrs., as the same speed can occur with standard or mini, but in a 2 or 3 lap qualifying session the ability to get up to speed quicker may be all that you need. In a race, the recovery time is muck quicker as well.
Nobody said anything about science, who cares about that, all i care about is performance on the track and what the lap times say.
 
You must log in or register to reply here.
Back
Top