clarification needed on driven clutch tuning ( spring colors)

[mouthfulloflake]

30 series, and I am trying to get more grunt, or bottom end.

stock yerf dog, tecumpseh ohh60, currently has the green spring installed

which driven spring gives the most bottom end?, I have read, but I have also seen conflicting information.

I ordered a yellow driven spring today, but now I am wondering if that is the opposite of what I need?

 

[Alex.bikes]

Yellow spring I believe is the lowest rpm engagement. I would go for a black spring or green. this changes the engagement of the converter on the rpm. with the higher rpms you should get more low end power out of your engine with those.

 

[mouthfulloflake]

Thanks Alex
that is certainly NOT what I want haha

I wish Comet had a chart or something, I have exhausted my google fu at this point.
My desire is the opposite of what you have described

 

[panchothedog]

To get a stronger hole shot you need to raise the engagement rpm. Best way to do this is by putting in stronger garter springs on the driver clutch ( the one on the engine ) and or lighter weights in the driver. Using both methods you can adjust take off rpm from about 1600 to 4000 rpm. Comet does have a chart as well as several of the major kart supply shops. The garter springs come in about
6 or 7 different strengths and are cheap. About $10 A set. The light weights
( aluminum) are around $35 for a set. BTW, the green spring that you have in the driven clutch is the best one for what you are trying to accomplish. The yellow spring is weaker an will shift into high gear sooner, killing low end grunt. I have never heard of a black spring for the driven unit. Not trying to say it doesn't exist,
But with 3 off road ( big tall tires ) karts and a mini bike, all running 30 series torque converters and hopped up engines I have been playing with these converters for several years. Hope this helps you out some.

 

[mouthfulloflake]

That helps Pancho, thank you.

ive read and watched Utube about a red spring too.

if anyone could link a definitive Comet chart to the driven pulley springs and color it would help me,

I have searched, will try google again with some different search terms

 

[mouthfulloflake]

see, this adds to the confusion in my head.



"The driven comes with the green spring and it is under load in the middle hole "This is the stock set up"

You can adjust it one hole to delay full overdrive; next step up requires buying the yellow spring to get more delay. "

quoted from here:

HOW TO TUNE YOUR TAV2 and a little Comet history : CycleKart Tech Forum : The Cyclekart Club

I don't know if you know but Comet Industries went into receivership in 2009 and we almost lost the TAV unit altogether ! A lot of you might know it was bought lock stock and barrel. But by who?.........well CPC Certified Parts Corp. and by 2010 the TAV lives to fight another day.

www.cyclekartclub.com

according to that write up the yellow spring will delay full overdrive longer than the stock green spring.

 

[BrownStainRacing]

Tune your driver 1st.

1 white spring and 1 stock spring with stock zinc weights, will be aprrox 2600 rpm engagement, this works good for stock engines.

2 white springs will be 3100 rpm engagement, this works good for engines that can hit 4200 rpm MAX.

Google Image Result for https://support.ombwarehouse.com/hc/article_attachments/115011690428/image_2017050312194533.png

 

[mouthfulloflake]

also here, he references the yellow spring as "stiffer"
watch at 11:55

\\

 

[mouthfulloflake]

Tune your driver 1st.

1 white spring and 1 stock spring with stock zinc weights, will be aprrox 2600 rpm engagement, this works good for stock engines.

2 white springs will be 3100 rpm engagement, this works good for engines that can hit 4200 rpm MAX.

Google Image Result for https://support.ombwarehouse.com/hc/article_attachments/115011690428/image_2017050312194533.png

I am perfectly happy with the RPM engagement point
Do I still need to mess with it?

if anything Id want it to engage at a lower RPM, assuming it makes enough power at lower RPM not to stall.

 

[BrownStainRacing]

I am perfectly happy with the RPM engagement point
Do I still need to mess with it?

if anything Id want it to engage at a lower RPM, assuming it makes enough power at lower RPM not to stall.

Let's do some quick math, and maybe you will see what I'm saying.

Let's say your engine makes 5 ft lbs torq at 2200 rpm, and you are trying to get more low rpm pull outta it.

2.7:1 low side of the t/c

Let's say you have 6:1 gear ratio.

Now
2.7 x 6 x 5 = 81 ft lbs of torq to the tires.
Trust me,.....that's now much!!!!

Now at 3000 rpm, the engine will have around 8 ft lbs, maybe more maybe less, but I know it will have more then 5 at 2200 rpm.

Math again
2.7 x 6 x 8 = 129.6 ft lbs to the tires.

129 will always get weight moving faster then 81.

Make sense????

 

[mouthfulloflake]

sure, but I want that 129 ft lbs before the converter goes to its higher ratio.

 

[BrownStainRacing]

It will never get into high, if it won't make torq to the tires on the low side.

Good luck, I wish you the best

 

[bob58o]

There seemed to have been a little confusion.
Forgive me if everything I posted was already covered.

Garter springs in Driver Unit
compression spring in Driven Unit

The standard driven spring on knockoff 30 series comes red. The yellow spring is stiffer. I believe the genuine comet driven spring is green.

The 2ndary clutch spring has 3 preload settings. The yellow spring is stiffer than the red

 

[bob58o]

Where might an OHH60 make peak TQ?
Searching for gx200 TQ curve shows it starts to fall @ ~2500 RPM.

 

[bob58o]

If you want more low end, get a jackshaft sprocket with fewer teeth.

or since F= ma, you could loose weight to increase acceleration.

 

[bob58o]

7” Driven Unit turns 2.7 :1 in low into 3.1 :1 in low.

 

[BrownStainRacing]

Where might an OHH60 make peak TQ?
Searching for gx200 TQ curve shows it starts to fall @ ~2500 RPM.
View attachment 145855

The gx200 has a 54mm stroke.

The tec 00H60 has a 49mm stroke.

I can't see a 49mm stroke making much torque under 2500 rpm.

The gx160 is 45mm stroke, it won't pull jack $hit under 3300 rpm.

Tecumseh OHH60 Engine: Specifications and Technical Data

Tecumseh OHH60 Specifications: Maintenance data, Service intervals, Carburetor adjustment, Torque Specs, Service data, Oil and filter, Valve clearance

tractorgearbox.com

 

[bob58o]

I can never remember what the numbers like 168F mean but I’m guessing this might be a 160, 200, and 390cc? Perhaps?

Also not sure how accurate these graphs are.

 

[mouthfulloflake]

It will never get into high, if it won't make torq to the tires on the low side.

Good luck, I wish you the best

It spins the tires at take off if I floor it, and then it accelerates until I feel the ratio change and by then its too fast for my terrain.

 

[mouthfulloflake]

Thank you Bob58o!

that clarifies what I thought about the spring colors, and I had read about the 3 holes to fine tune.
I very much appreciate you answering my questions!

The 7" driven is what I have, lucky me!

I will install the yellow spring and see what happens.