Lock Out/Lock-Up Tuning

[SlowerThanYou]

Baseline, Base Pressure, Arm Weight...........................!!!!!!!!!!!!!!!!!!!!!!!

 

****** IMO, the Baseline tune-up is the single most important step/start in setting up the lock-up. ******

 

It doesn't matter if you think your baseline is correct/not correct or even if it's your 1st time using/setting up the lock-up. It's a known reference to make changes from, if the change(s) don't work go back to your Baseline. If a change(s) works it becomes your new baseline!

 

Pages 15 & 16 have the procedures/step for the Baseline. I will keep them there, but also add them to this post when I have time for easy reference.

[SlowerThanYou]

This is the earliest information I found on clutch tuning. While it doesn't get into specifics, it covers applications pretty good.

 

How does this apply to us? It uses the priciples of primary clutch pressure & centrifugal force. The same as our quads with lock-ups.

 

For technical support call 619-422-1191 (7am to 5pm PST) • 24 hour fax: 619-422-9067 • www.crower.com 181

CROWER CLUTCHES

Since their inception in 1966, Crower clutches have

been regarded as the ultimate solution to high horsepower,

high torque, power to ground control. There is

no other clutch available on the market that can

harness the extreme power output of a competition

engine and control it as accurately and consistently as

a genuine Crower clutch. Our ongoing trackside

research and development program insures you of the

latest and most innovative components available.

THE “CROWERGLIDE”

The most copied clutch in racing, the original “Crowerglide”

incorporates a completely centrifugal design

and is totally adjustable. It was the industries first real

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today. Available in two through five disc setups, in

your choice of six or twelve stand configurations to fit

most engine/transmission combinations. Features

include fully CNC machined 7075T6 billet aluminum

pressure plate assembly, including stall speed springs

and counterweights. Adjustable stands come standard

on all units except the 8" mini “Crowerglide.” Available

in 8", 10", 10.7", 11" and 12" models to compliment

just about any application. All units are shipped

complete with flywheel bolts, washers, one pilot

bearing, feeler gauges, additional counterweights and

instructions. All “Crowerglide” clutches and related

components are fully S.F.I. certified.

 

POPULAR APPLICATIONS

• Truck and Tractor Pulling

• Drag Racing

• Sand Drags

• Monster Trucks

• Mud Racing

 

HOW TO ORDER A “CROWERGLIDE”

Due to the variety of applications and amount of

variables involved in building a clutch that will function

properly in a given vehicle, call Crower’s Clutch

Department at 619-424-6758 for personalized support

or fax the following information to 619-424-7129.

• Engine make

• Application or class of competition

• Estimated rpm power range

• Transmission spline info (O.D. and number of teeth)

11"

DIESEL GLIDE

10.7"

TITANIUM GLIDE

11"

12 STAND GLIDE

Centrifugal CrowerGlides clutches

 

 

CROWER PEDAL CLUTCHES

Unlike the completely centrifugal “Crowerglide,” the

Crower pedal clutch offers the conventional style foot

control launch combined with centrifugal assistance

and static spring adjustment. This highly versatile

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cover a wide variety of applications and is available

without a starter gear for blower start engines. Standard

features include full 7075T6 construction, titanium

adjusting stands and dial indicator for setting the

pressure plate height. All units are fully S.F.I. certified

and shipped complete with flywheel bolts and washers,

one pilot bearing, additional counterweights and

instructions that include static spring charts and

installation procedures using the dial indicator.

 

POPULAR APPLICATIONS

• Alcohol Dragster & Funny Car

• Pro Stock & Pro Modified

• Comp Eliminator

• Sand Dragsters

• 2 & 4 Wheel Truck Pullers

 

HOW TO ORDER A PEDAL CLUTCH

Due to the variety of applications and amount of

variables involved in building a clutch that will function

properly in a given vehicle, Crower recommends that

you call our Clutch Department at 619-424-6758 for

personalized service or you can fax the following

information to 619-424-7129.

• Engine make

• Application or class of competition

• Estimated rpm power range

• Transmission spline info (O.D. and number of teeth)

PARTS & SERVICE

Crower offers complete service and repair on all Crower

clutches and Crower products, as well as technical

support. All clutches and components returned for

service and repair will be subject to a $60.00 minimum

tear-down and inspection charge. Used parts requiring

machine work will be subject to a machining charge

based on prevailing rate. All used parts not meeting

Crower’s specifications will be replaced at the

customer’s expense.

9"

PRO COMP

10"

PRO SPORTSMAN

10.7"

TOP SPORTSMAN

Pedal Clutches clutches

 

Back to the original question of to cut a clutch spring or not. You don't have to cut a spring to get the needed results. This works for us for many different reasons. It allows us to adjust the pressure to what we want.

 

Yes, we could have custom springs made, but that would cost $$$. Plus, the bulk of springs you would have to buy. Then we probably just cut some of them anyway.

 

We have many different types of springs ranging from: stock Banshee, yzf450, EBC, Barnett standard/heavy, FAST Racing and probably a couple more that I forgot about. The important thing is to mix, match and sometimes leave out springs to get the desired results.

 

Now, it has been brought up in the past using a spring tester. This is needed, along with recording the data. For us we record the pressure in lbs. & one other measurement when testing the spring. I should have taken a picture & I'll try to get one posted soon of a simple set-up.

 

Here's our basic spring pressure tool set-up around $100. You can upgrade to a Rimac Spring tester starting around $600 and the digitals are even higher.

 

 

 

 

I didn't cover everything on the springs & some of it may come out later. I think it pretty much covered the orginal posters question.

 

Now the second question the poster had "see i just want to drop the clutch and it slip on it own just a slight bit"

 

This started the second discussion. To slip the clutch manually or drop the clutch. We prefer to drop the clutch lever & allow our clutch tuning to do the task.

 

We follow the trends of professional drag racers & the trends of our drag racing experience. We found around 90% of what works from our 30 years drag racing experience, works very well for our quad drag racing.

 

I provided some of the research information I found. I kepted an open mind, used our experience, others experience and applied it to our ATV clutch for drag racing on the asphalt, hill shooting & 300' sand.

 

So, to drop the clutch or not? I'm going to use what the vast majority of top professional clutch racers do. Drop the clutch and let the clutch tune-up do its proper task. It has worked for us & our friends very well. Is it for everyone, I'm sure it's not.

Edited October 12, 2013 by JUAN

[SlowerThanYou]

Its def not gonna be for everyone and many people that pull my clutch lever cant wrap there heads around it

 

The old clutch lever pull deal. I have a good Puerto Rico friend that said the same basic thing. He pulled the clutch lever on a few quads at the PS Gilbert, LA. race. He was surprised at how easy they pulled.

 

I'm sure you could use a spring scale to measure the clutch lever pull. IMO that would add in another factor of the clutch cable condition.

 

Anyway, you have an easy clutch lever. That leads to the next subject of arm weights. There are many different ways of doing the arm weights. We choose to cut the majority of the weight and then use washers to fine tune the total weight.

 

 

 

[N2deepRacing]

What lock out you have there? I have done alot of studying on this and you have the right ideal going their! We also cut out weights like that to. Do I know you? I race with the Titan guys.

[SlowerThanYou]

What lock out you have there? I have done alot of studying on this and you have the right ideal going their! We also cut out weights like that to. Do I know you? I race with the Titan guys.

 

It's a Chuck Wilburn Multi-Stage. We have done a lot of R & D on clutch components, machining, coatings, cryo, maintenance/inspections and different materials to name a few things. While most of this was done with around 800 runs on asphalt. We also used it for testing sand hill shooting with around 80 runs. The most recent of the testing has been on 300' sand with about 25 runs. We are going back to the 300' @ Dome Valley, AZ. next weekend. Plus, we are planning to run Bakersfield, CA. the end of Feb.

 

You know me as 1700camaro, does that answer your question.

Edited January 29, 2012 by SlowerThanYou

[SlowerThanYou]

here is a question then

 

have you found a clutch plate that will slip through the run and not turn to toast in a few passes..

 

I'm planning to cover all aspects of the clutch eventually. We snuck an extra unexpected sand race in & I'm pretty busy.

 

Anyway, glad someone has a question. There have been plenty of them at the track.

 

IMO the ideal set-up will only slip to around 30' out of the gate. Plus, you want a little slip on the gear changes. The slip on the gear changes, I haven't totally mastered yet.

 

When we originally started this science project back in 2005. We were getting 4-5 runs out of a clutch. It took us a couple years to get 40-50 runs. The current clutch we have in now has over 100+ asphalt runs & 35-40 sand runs. I'm doing my last servicing of it to hopefully get another 20-30 runs out of it

[cce12]

Hey I have another question for you. I'm new to the lockout tuning world..... I'm building a 10 mil cub for 1/8th mile on asphalt. What would be a good starting point to setup the lockout? I've been following these threads, I'm trying to learn about this but until I get to the track and get to test/tune and tune different things its hard to tell. My best 60 foot times I can get out of my 4mil stock cylinder is 1.63 using 3hd/3stk springs. Any recommendation would be appreciated.

CE

[SlowerThanYou]

Hey I have another question for you. I'm new to the lockout tuning world..... I'm building a 10 mil cub for 1/8th mile on asphalt. What would be a good starting point to setup the lockout? I've been following these threads, I'm trying to learn about this but until I get to the track and get to test/tune and tune different things its hard to tell. My best 60 foot times I can get out of my 4mil stock cylinder is 1.63 using 3hd/3stk springs. Any recommendation would be appreciated.

CE

 

You need to baseline your current set-up. What's your base pressure total weight @ the springs installed height? What's your arm weight in grams on each arm?

 

Your 60' time will tell the story. You keep adding or taking away base pressure to improve the 60'. If it bogs or spins excessively you have too much. If it drives thru the clutch (mushy) you don't have enough pressure.

 

Your arm weight is used to lock-up or stop the slip. This will usually show up in the higher gears 5 & 6. If it show up earlier, you are really off with the arm weights.

 

There's really much more than what I've covered so far. I'm not reinventing the wheel here. The info is out there & I researched to find it. Then I used a little common sense to apply the information to our needs.

 

I can probably cover everything I know about clutches, but I don't plan on giving away everything. Anyway, It still comes down to the tuner to make the right decisions to make it work with the rest of the combination

[springer]

just found this, but very interesting. on that mutli-stage setup, it looks like there is different weight on opposite arms, is it? if so, do you start tuning by getting the lighter side set first and then add weight to the heavy side to get the upper lock you want? also, would you mind sharing what clutch and steels you have found to last the longest? you mentioned being able to extend a clutch life quite a bit, mind sharing any details on that?? if not, i know a lot of this stuff is hush hush and everyone needs to do their own r&d. i tried to pm you, but it wouldn't let me for some reason.

[SlowerThanYou]

just found this, but very interesting. on that mutli-stage setup, it looks like there is different weight on opposite arms, is it? if so, do you start tuning by getting the lighter side set first and then add weight to the heavy side to get the upper lock you want? also, would you mind sharing what clutch and steels you have found to last the longest? you mentioned being able to extend a clutch life quite a bit, mind sharing any details on that?? if not, i know a lot of this stuff is hush hush and everyone needs to do their own r&d. i tried to pm you, but it wouldn't let me for some reason.

 

Some one has a good eye & I wondered if anyone would pick up on it. With our multi-stage we can stall our lock-up arms by changing springs in the tower (under patented). There are 6 springs, 1 for each arm. We tune the arms with both the springs & weight.

 

I have also been tuning on standard lock-ups also & have a pretty good data base of information.

 

As for the clutch frictions we primarily use Yamaha fzr 1000 fibers. We have played with Barnett kevlar and want to try carbon fiber frictions some time soon.

 

As for the steels, we use different types of materials, treatments & coatings. We have a pretty detailed maintenance & inspection program for the clutch frictions & plates.

 

As for being hush hush this information has been out there starting around the 1960s. It's not always easy to find! A few of us have done a good job of compiling it, then testing it in our quads. The information isn't always staring you in the face, it has to be adapted to our/your platform.

 

I will be updating some more information in the future. I'm going to keep the closely guarded sectrets to myself & a few friends.

[SlowerThanYou]

I got a few things to share about the clutch/primary springs that hasn't been covered yet. The primary springs control the initial slip at the drop of the clutch & out to around 15' off the line. It can be extended some with a multi-stage lock-up. The lock-up arm wieght starts with tire rotation/slip/wheel speed or engine rpm climb depending on the lock-up being used. I'll give two different examples:

 

1st, drop the clutch & the motor immediately bogs or tries to kill. If everything else is good with your engine tune-up. The I would remove a certain amount of base/static spring pressure. How much you remove is based on many things, but primarily your experience. We have a certain way we do this with shims. We can add or take away pressure with .005 - .062 shims & everything in between.

 

2nd, drop the clutch & the rpm/wheel speed climbs. You get off the line & about 5'-7' and the motor bogs. This is getting to the transition area where the lock-up arms are coming in. I would 1st remove a little weight from the arms, but depending on other factors you could remove base/static pressure.

 

There are a just a few examples & we are starting to get away from the primary springs. The next area I'll cover, will be the lock-up arms.

 

I didn't cover any of the primary spring spring pressures (static pressure). I will say this, a standard lock-up will require less static pressure than a Multi-Stage hub/basket driven lock-up.

 

Lets start with the arm weights. IMO, there's only one way to measure the arm weights. We use a small pocket scale bought from Harbor Frieght for around $14. We prefer to use grams for weighing the arm weights. We used to use a + or - of .1 gram for our standard, but we find ourselves trying to get it perfect as possible with the cheap scale.

 

The Multi-Stage lock-ups have more adjustability than the standard lock-ups. With standard lock-ups, the arms start applying a lot quicker. Hence the reason to run less static spring pressure to kind of crutch its lack of adjustability.

 

I think it was Springer that caught on to us using different weights on the arms. We could & sometimes do use different tower arm springs to change/delay the arm engagement. It's a lot easier to use all the same tower spring pressures & adjust the weights for arm engagement.

 

Next time I'll provide some examples for tuning the arm weights.

[Wheelman Chassis]

Hmmm, guess I need to get around to the next topic. Got to find time & the forum stuff is low on the priority list.

 

I think ths is a great topic, i have been tuning street bike clutches like this for some time now.

 

Brian,i thnk maybe if we touch on the ideal launch(limited tire spin, keeping the motor at peak power and maximizng forward motion in the first 60') the facts and info you share may be easier for some guys to grasp.

 

 

Id like your info/opinion on judging initial base presure and the poitive and negative effects of to much, also not enough.

 

From my tuning to much initial spring/base pressure will cause excessive tire spin or a bog.

To little pressure will cause little to no tire spin,and "driving through the clutch/slip" resulting in heated,glazed,and overworn clutches. This will slow et and 60'.

 

please share some more info this post can help many of our members to grasp this topic.

 

Chris

[SlowerThanYou]

I think ths is a great topic, i have been tuning street bike clutches like this for some time now.

 

Brian,i thnk maybe if we touch on the ideal launch(limited tire spin, keeping the motor at peak power and maximizng forward motion in the first 60') the facts and info you share may be easier for some guys to grasp.

 

 

Id like your info/opinion on judging initial base presure and the poitive and negative effects of to much, also not enough.

 

From my tuning to much initial spring/base pressure will cause excessive tire spin or a bog.

To little pressure will cause little to no tire spin,and "driving through the clutch/slip" resulting in heated,glazed,and overworn clutches. This will slow et and 60'.

 

please share some more info this post can help many of our members to grasp this topic.

 

Chris

 

1st, I would like to thank you for time on the phone today. I also spent about 2 hrs. talking with Titan Racing today. The clutch tuning was the main topic also, among others.

 

I was hoping to be a little farther along on this topic, by now. You bring up some very good points and maybe I ought to re-baseline or clarify some of the information. Stay tuned & be patient.

 

Bryan

[Wheelman Chassis]

1st, I would like to thank you for time on the phone today. I also spent about 2 hrs. talking with Titan Racing today. The clutch tuning was the main topic also, among others.

 

I was hoping to be a little farther along on this topic, by now. You bring up some very good points and maybe I ought to re-baseline or clarify some of the information. Stay tuned & be patient.

 

Bryan

 

Any time sir, it was my pleasure. ill keep checking in here and ill add my .02 when i think its relivant and ill keep the questions coming.

 

 

Chris

[SlowerThanYou]

This sums it up better than I could explain! Where it says car, insert ATV and we require a little higher rpm than used in the example. Other than that, that phrase pretty much hits the nail on the head. There's much more that goes along with it to make it work effectively & more efficient.

 

 

"What is the optimum clutch setup?

 

At the starting line, the optimum clutch setup will allow you to apply as much power as possible to the rear wheels without losing traction. This is accomplished by controlling the amount of clutch slippage with adjustments to the static and centrifugal pressures. For example: The clutch could be set with moderate static pressure and the correct amount of centrifugal weight to allow the clutch to slip as the car leaves the starting line at relatively low RPM. As the engine RPM increases in first gear, the centrifugal assist increases, gradually locking the clutch up and applying full power to the rear wheels. If the clutch slips too much off the line, additional static pressure could be added, or the launch RPM could be raised to allow the centrifugal weights to begin locking the clutch up sooner. If the track conditions were poor, the static pressure could be reduced or the launch RPM reduced in order to allow more slippage and maintain traction. "