Clutch engagement
- Thread starter Phineas
- Start date
paulkish
old fart
Generally your clutch engagement is set to come in at or around peak torque. You'll probably get a lot of advice and opinions on here about if it should be exactly peak torque, a little below or a little above. But the general consensuses will be around peak torque.
There are different ways of finding out where your engines peak torque rpm is. One is ask your engine builder. If you tell us the engine your required to use where your racing purple plate, you'll also get a lot of numbers for what engagement rpm you should shoot for. A general consensuses for rpm will show itself to you from what is recommended.
There's also a scale method for finding peak torque and the rpm you should engage your clutch. But if your new what your driver needs most is seat time and just go with what you feel seem right for what you learn on here and at the track.
Your question about setting the idle speed I think is pretty much a new question on here. I'm sure some really get into idle speed and you'll hear from them but I think it's mostly you just want it high enough so the engine won't stall out on you. The rest of it is up to how your driver uses the gas pedal.
That being said and you saying it's purple plate, it would be about how your driver might be able to move their gas pedal up and down too much, over heating the clutch because of it engaging too often, and/or not engaging well enough.
Depending on your driver it will take either a little or a lot of explaining and a little or a lot of seat time to fix. Idle is for idle and when you go it's up to the driver to either bring the engine up to speed quickly or not so quickly.
I see another possibility where you driver just does not have enough experience yet to go fast enough to let the clutch fully engage. In that case your either have to make the clutch engage closer to idle speed loosing power because the engine is operating below peak torque or your just going to have to let your new driver burn up a clutch or two until they can go fast enough.
It's not uncommon to hear the engine of a new driver take for ever to get up to speed. It's either engage too soon, lug the engine and make it take awhile to get up to speed or burn up the clutch. After the first clutch burn up many dads and moms let it lug until seat time allows them to raise engagement speed.
There are different ways of finding out where your engines peak torque rpm is. One is ask your engine builder. If you tell us the engine your required to use where your racing purple plate, you'll also get a lot of numbers for what engagement rpm you should shoot for. A general consensuses for rpm will show itself to you from what is recommended.
There's also a scale method for finding peak torque and the rpm you should engage your clutch. But if your new what your driver needs most is seat time and just go with what you feel seem right for what you learn on here and at the track.
Your question about setting the idle speed I think is pretty much a new question on here. I'm sure some really get into idle speed and you'll hear from them but I think it's mostly you just want it high enough so the engine won't stall out on you. The rest of it is up to how your driver uses the gas pedal.
That being said and you saying it's purple plate, it would be about how your driver might be able to move their gas pedal up and down too much, over heating the clutch because of it engaging too often, and/or not engaging well enough.
Depending on your driver it will take either a little or a lot of explaining and a little or a lot of seat time to fix. Idle is for idle and when you go it's up to the driver to either bring the engine up to speed quickly or not so quickly.
I see another possibility where you driver just does not have enough experience yet to go fast enough to let the clutch fully engage. In that case your either have to make the clutch engage closer to idle speed loosing power because the engine is operating below peak torque or your just going to have to let your new driver burn up a clutch or two until they can go fast enough.
It's not uncommon to hear the engine of a new driver take for ever to get up to speed. It's either engage too soon, lug the engine and make it take awhile to get up to speed or burn up the clutch. After the first clutch burn up many dads and moms let it lug until seat time allows them to raise engagement speed.
paulkish
old fart
I see 2800 with no weights per shoe, 2600 with one weight per shoe and 2450 with two weights per shoe. And the Hillard add description of their clutch it says weights are not included with the clutch and that it's not lock up speed, it's when the shoes first touch the drum. It's very confusing to me what the clutch will do per what weights you buy and I can see why it's confusing to Phineas.
If I assume he bought a new clutch and it did not come with weights, he's likely asking how many weight should he put in each shoe. I think if he has a new clutch out of the box, it's going to engage too high and probably burn up with a new purple plate driver.
My guess after looking at the Hillard site is if you bought a new clutch or if you don't know, to start out put weights in both shoes. That way the clutch will engage as soon as possible, probably lugging the engine down and you have a starting point. Next try removing a weight from each shoe and see what happens.
And never have used a clutch like that it is ALL A GUESS.
All this post is my reading of the pdf on engagement speed from the Hillard site at: http://www.bmikarts.com/Inferno-Flame-34-Bore-Racing-Clutch-from-Hilliard-_p_809.html
I'm going to go out on a limb and say/repeat, with a rookie driver being new. Start off as Kj26 said with the white springs and as I'm suggesting 2 weights in each shoe. Then if the engine lugs too much and you think your young driver is ready for it, take one weight out of each shoe and see how they do driving. Next step is take the second weight out of each shoe. If they do ok then your next step is to install the black springs with 2 weights and continue on with the process of getting better and faster.
If your driver gets the the point where no matter what you do they just don't get any faster, then you forget about the clutch and figure you need to get better at kart setup or tire setup. Always figure your young driver is going to be able to learn faster driving then you are able to learn to give them something good to drive. ...
>>>>> I MUST add I have no clue never having ever used a clutch like that. PLEASE this is the beginner section, if i'm giving out bad advice to a new karter PLEASE someone straighten my wrong advice out.
... and Kj26, I'm not saying your wrong. It's that I went to the site and learned the white springs have 3 different settings. Maybe Hilliard would help out here and give some advice to a new kart racer???????
How about throwing some customer support at us, your clutch looks really cool and able to do the job. ??? ...
Thanks for all the responses. It is a new clutch ( we used in 4 races so far ). We started with 2 black and 2 whites. And as I got better at tire prep and him as a driver he was getting faster. Just wanted to make sure I was going in the right direction with the clutch set up.
Thanks again for responding this site has really helped with so many questions I have had so far.
Thanks again for responding this site has really helped with so many questions I have had so far.
paulkish
old fart
Your question was about idle rpm. Idle is just that idling. Then you push the gas pedal and go. Next looking at the Hillard chart your setup to start clutch engagement at 3400rpm. That's either the right starting point putting you close or dead on with peak torque or it's not. You either need to know where peak torque is from your engine builder, let us know more about the engine or use the scale method. After that it's about the weights and springs you use.
Kj26 has you engaging sooner per the chart at 2800 if it's also using no weights in the shoes.
I can see going with what Kj26 recommended depending on your kid and how they do on the track.
Assuming 3400 engagement is ok, I'd guess you might want to try 4 black, 2 weights in each shoe.
The Hillard site also talks about leading shoes. My thoughs are I'd want to have all shoes 'leading' shoes.
Below is from their site:
Shoe Orientation is also tunable and changes the engagement characteristics of the clutch.
Shoes with a mass in front of the driving lug (the 4 lugs on the hub that drives the shoes), with respect to the direction of rotation are called leading shoes. Leading shoe will have the tip of each shoe pointing towards the direction of rotation.
http://www.hilliardextremeduty.com/media/8444-7f-019.pdf
Kj26 has you engaging sooner per the chart at 2800 if it's also using no weights in the shoes.
I can see going with what Kj26 recommended depending on your kid and how they do on the track.
Assuming 3400 engagement is ok, I'd guess you might want to try 4 black, 2 weights in each shoe.
The Hillard site also talks about leading shoes. My thoughs are I'd want to have all shoes 'leading' shoes.
Below is from their site:
Shoe Orientation is also tunable and changes the engagement characteristics of the clutch.
Shoes with a mass in front of the driving lug (the 4 lugs on the hub that drives the shoes), with respect to the direction of rotation are called leading shoes. Leading shoe will have the tip of each shoe pointing towards the direction of rotation.
http://www.hilliardextremeduty.com/media/8444-7f-019.pdf
alvin l nunley
Site Supporter
Most consider that engagement is where the clutch holds the engine when you get it full on. That point will be higher in RPM than when the shoes first start touching the drum.
I've seen where plate motors reach peak torque at a lower RPM than non-plate engines, so some advice (unrestricted setting) could be higher then you want. Try different settings.
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Kj26
Member
Sry, was down in AC for the indoor race.
I'm not into all that technical rpm stuff, Al and Paul have that figured out. We've been racing long enough and have tons of support behind us, so when they tell us to do something with the clutch I just do it and don't ask.
Here's a little more, seeing my youngest is going to unrestricted this year, we ran 4 whites in blue plate also. Always took off like a rocket.
I know there's no extra weights in our flames.
I'm not into all that technical rpm stuff, Al and Paul have that figured out. We've been racing long enough and have tons of support behind us, so when they tell us to do something with the clutch I just do it and don't ask.
Here's a little more, seeing my youngest is going to unrestricted this year, we ran 4 whites in blue plate also. Always took off like a rocket.
I know there's no extra weights in our flames.
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alvin l nunley
Site Supporter
I don't know if you knew this, but you always want the clutch set to the engines peak torque RPM.
Look at the formula; RPM X torque / 5252.1 = horsepower.
If the clutch is holding the engine at peak torque, that torque gets transferred to the rear axle, through the chain, and with peak torque at the rear axle you have peak horsepower at the rear axle. While the clutch is slipping, the horsepower at the engine, and the horsepower at the axle are different.
Look at the formula; RPM X torque / 5252.1 = horsepower.
If the clutch is holding the engine at peak torque, that torque gets transferred to the rear axle, through the chain, and with peak torque at the rear axle you have peak horsepower at the rear axle. While the clutch is slipping, the horsepower at the engine, and the horsepower at the axle are different.
paulkish
old fart
Al, the clutch has to slip or when you start to accelerate the or engine will go below peak torque. If it slips too much then the engine will go above peak torque. All you worry about and write about is engagement, then instantly weather or not the clutch is locked up. Again it's because you come from a sprint background where to be successful you have to average things you do and pick a place on the track to increase your advantage. That place may be anywhere on the track. LTO racing Al all turns on the track are closer in characteristics and how you use your chassis, engine is required to be fine tuned much more then you experienced sprint racing.
I suggest Al you go to this Hillard Flame Clutch site and read the manufactures advice sheet.
http://www.hilliardextremeduty.com/media/8444-7f-019.pdf
What you do need to read learn about and comprehend Al is the manufacture gives a reference to set when the shoes first contact the drum. Then Al the manufacture explains how to adjust the clutch to control how much delay or time there is between when the shoes begin to operate and when lockup occurs.
Hoping you have now read the manufactures instructions and understand about how it is possible to control the amount of time it actually takes the clutch to work, I'll ask you a question Al.
Do you now see how a lot of conversation you constantly argue with is about racers reporting because of experience Al, how they set their clutches so that the start of engagement to lockup will allow the clutch to slip and maintain speed at peak torque, from start of engagement to finish. Once acceleration is brought smoothly maintaining the ability to keep the engine running at peak torque, it's continue on with your acceleration until you need to slow down.
Once moving Al and into the turn chassis, tires, engine, clutch and drivers foot on the accelerator, are matched for other reasons. The reasons again are finely tuned reasons Al. Their far beyond your expressed comprehension on here of, your going this or that speed with the engine at this or that speed, your clutch must be slipping and heat occurs this and that.
Experience Al so often can't argue with cut and dry facts when you Al the presenter of the cut and dry facts, has no grip on LTO function and how a LTO is used on the track.
I suggest Al you go to this Hillard Flame Clutch site and read the manufactures advice sheet.
http://www.hilliardextremeduty.com/media/8444-7f-019.pdf
What you do need to read learn about and comprehend Al is the manufacture gives a reference to set when the shoes first contact the drum. Then Al the manufacture explains how to adjust the clutch to control how much delay or time there is between when the shoes begin to operate and when lockup occurs.
Hoping you have now read the manufactures instructions and understand about how it is possible to control the amount of time it actually takes the clutch to work, I'll ask you a question Al.
Do you now see how a lot of conversation you constantly argue with is about racers reporting because of experience Al, how they set their clutches so that the start of engagement to lockup will allow the clutch to slip and maintain speed at peak torque, from start of engagement to finish. Once acceleration is brought smoothly maintaining the ability to keep the engine running at peak torque, it's continue on with your acceleration until you need to slow down.
Once moving Al and into the turn chassis, tires, engine, clutch and drivers foot on the accelerator, are matched for other reasons. The reasons again are finely tuned reasons Al. Their far beyond your expressed comprehension on here of, your going this or that speed with the engine at this or that speed, your clutch must be slipping and heat occurs this and that.
Experience Al so often can't argue with cut and dry facts when you Al the presenter of the cut and dry facts, has no grip on LTO function and how a LTO is used on the track.
paulkish
old fart
"I don't know if you knew this, but you always want the clutch set to the engines peak torque RPM."
Al setting the engine to peak torque is a reference only. Experience and if your thinking of on the starts, how the clutch is set depends on how fast the kart will be going when the start flag is thrown or when the running start of acceleration occurs.
Al setting the engine to peak torque is a reference only. Experience and if your thinking of on the starts, how the clutch is set depends on how fast the kart will be going when the start flag is thrown or when the running start of acceleration occurs.
paulkish
old fart
Phineas, I hope you got the understanding you were looking for from this thread and I'm not messing things up for you. If I am please say so and I'll try my best to take arguing with Al off this thread. I can take my replies and put them in a new thread so to not muddy up your question more then already done. Sorry
alvin l nunley
Site Supporter
It's becoming more and more obvious to me that you really don't understand what I'm saying. Your replies are becoming incomprehensible to me!
paulkish
old fart
Phineas, rather the bicker back and forth with Al screwing up your thread even more, I did start a new thread to take the hyjacking back and forth away from here. I hope you got an answer you were looking for. If not please say so and a moderator might be so kind as to get rid of the hyjacking stuff by both Al and me.
edit: I started my clutch question post in the clutch section.
edit: I started my clutch question post in the clutch section.
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alvin l nunley
Site Supporter
"What it's supposed to be set to" "what I've been told to set it to" what's the difference? Where do you now set it? What class and what engine? Do you have any dyno run charts?
paulkish
old fart
Al, with all due respect not everyone has your qualifications and many racers rely on input from others.
Weather we were sprint racing, LTO racing or car racing, there were and are some in each area who we respected their knowledge to the extent that when they suggest something, we do it.
If Kj26 and team have someone knowledgeable guiding them from watching on track performance, I have no reason to doubt, ... that's good nuff.
Weather we were sprint racing, LTO racing or car racing, there were and are some in each area who we respected their knowledge to the extent that when they suggest something, we do it.
If Kj26 and team have someone knowledgeable guiding them from watching on track performance, I have no reason to doubt, ... that's good nuff.
paulkish
old fart
"Thanks for the information. I guess what I am trying to figure out is if I go all white springs vs all black springs. Which set will give him more acceleration?"
Because of the amount of variables involved, you'll never know until you try it.
_______________________
"And I would think the other would give him more top end speed?"
How fast you can go on the straight is the result of how fast you exit the corner and available hp.
How fast you exit the corner is determined by how well you get through the turn from turn entry, to the start of acceleration.
How fast you enter the corner is about your perception of pain and the trust you have in your level of skill.
Some have too little trust, some have just the right amount of trust and some have too much trust. I guess turn entry can be called the Goldilocks Zone. ...
Because of the amount of variables involved, you'll never know until you try it.
_______________________
"And I would think the other would give him more top end speed?"
How fast you can go on the straight is the result of how fast you exit the corner and available hp.
How fast you exit the corner is determined by how well you get through the turn from turn entry, to the start of acceleration.
How fast you enter the corner is about your perception of pain and the trust you have in your level of skill.
Some have too little trust, some have just the right amount of trust and some have too much trust. I guess turn entry can be called the Goldilocks Zone. ...