Lock Out/Lock-Up Tuning

[m671054]

The lock up arms spin at trans input shaft speed dont they? Or do you run a basket mounted setup? Conventional dd style lock up would need the spring pressure to drive the basket speed up to get the arms to provide pressure. A spinning tire off the line would go to max lock up in effect.

[shanYE west]

your correct. I had a brain fart and wasn't thinking.. long offseason..

 

spring pressure is used to slowly ramp the speed of the input shaft (lock up pressure) So I guess what I was trying to get at is.. By adding locker weight.. its applying more pressure at a slower speed.. So if too much spring pressure is present. it will ramp the speed of the locker too fast applying too much pressure too soon and bog the motor. Is this correct?

 

I'm not the greatest at typing technical info..

[sleeper06]

you guys would die if you saw how chopped my springs are,i use a snowmobile cltch spring guage to measure pressure from goodwin performance,and a gram scale to measure weight on arms,i have went as far as taking arms off machining weight off,The key is a baseline and records .Diffrent tracks diffrent outcomes.Im just really suprised it took this long for everyone to mess with this shit

[Coupelx]

how long are clutches lasting for you guys?

[shanYE west]

you guys would die if you saw how chopped my springs are,i use a snowmobile cltch spring guage to measure pressure from goodwin performance,and a gram scale to measure weight on arms,i have went as far as taking arms off machining weight off,The key is a baseline and records .Diffrent tracks diffrent outcomes.Im just really suprised it took this long for everyone to mess with this shit

 

I think its been messed with for a long time.. just no one wanted to openly discuss their "trade" secrets. I've been tinkering a bit.. but not as indepth as some. I'm just a dune racer who occasionally goes to a track for TNT and even then.. I dont tune.. I just make passes. So you wont see any data books on my setups. I'm not that hardcore. I got some theories on clutch setup and have gotten pretty good results at the track in the past for being a dune racer.

 

Good topic and good info for sure.

 

http://www.ebay.com/itm/MINI-VALVE-SPRING-TESTER-NEW-PROFORM-0-300-LBS-/370607784786?pt=Motors_Automotive_Tools&hash=item5649f20352&vxp=mtr#ht_1544wt_910

[SlowerThanYou]

how long are clutches lasting for you guys?

 

When we first started in 2005 only about 5 runs. 2006 we started getting around 40 runs. Somewhere around 2008 we started getting 100 runs. The current clutch we have in has 200 + asphalt/sand runs. The clutch still performs well, but the quickest 60's sign off around 100-120 runs.

[SlowerThanYou]

Ok, so after you get the base weight measured and a baseline arm weight put on to start, all things recorded in my racers log its time to go to the track. I say its best to start with the same setup/tune up that you normally run as a baseline with the only differance being the clutch, this will give a better idea of what the changes have done to your times.

 

So, I roll into the beams, reach my desired launch rpm the lights come down , I dump the clutch and bbbboooooooooggggg!!!

 

Now assuming my gearing is right for speed/rpm in high gear at the end of the track, and my launch rpm stays consistant. Whats the next change these guys trying this should make?

 

IMO, I would reduce the amount of base weight on the clutch resaulting in more "slip" for the initial hit. OR If I belived the bike was very close to making a clean launch, I would raise the launch rpm at the line. Now with all this being said, If the bike did launch it would most likely suffer from excessive tire spin needing further clutch adjustments.

 

Bryan from your exp. what would the proper adjustments be, and how do the people reading go about these changes, and in what increments do they do them in for best results.

 

 

Chris

Wheelman Chassis

 

 

We all have different ways of doing things. My take is study experts in their specialty. That are consistent in making something work very well.

 

With that being said I will start with Wheelman's 1st para. He covered it pretty well, but I have a little different twist. You need to be well equipped with your clutch tuning kit/tools. We actually have a dedicated 3 drawer tool box. Plus, you need to work out a routine to quickly/effiecently make your clutch tuning adjustments. For the 1st time clutch tuner, you should have your baseline set-up logged/documented at home. I would start with your current set-up. I would make two runs to get the base line for that days conditions. Now, where do you start with your adjustments. Most cases I would recommend lowering the base spring pressure. Your 60' times will tell you if the change is correct or not.

 

Now, for your bbbbbooooooooggggggggggg scenerio. You have made some good basic recommendations already. If that bog run was on the 1st pass. I would come back & try it again. That situation happened to us in Feb & we started chasing our tails with the clutch base pressure. Long story on why it bogged.

 

Back to your BBBOOOOGGG scenerio. There are many different types of boggs & where they happen depends on the proper adjustment to be made. I will assume your bog was immediately at the drop of the clutch. When that happens it darn near kills the motor & sometimes it does kill it. With out a doubt I would try another pass. If the out come is the same. I would lighten up the base spring pressure.

 

Now, if it was close to making a clean launch. It really depends on what you interpet as close. I use a recent example we used on a very loose track. We were blowing the tires away on the initial hit. I choose to start lowering launch rpm to correct the problem. We starting with low 1.50s 60's and worked our way down to high 1.30s 60's. This was on what I call a poor track conditions. Anyway, I wish I had video of a few of the passes. The motor rpm was being pulled down to almost a bog. If I would of lowered another couple 100 rpm it probably would have bogged. We were walking a fine line with that set-up.

 

 

As for you last sentence, I hope I clarified your scenerio. I'm trying to provide some good info without spilling out everything. I firmly believe with spoon feeding you learn nothing. You need to feed yourself to actually learn/comprehend what's going on.

I hope people continue to ask question. They should be able to improve the clutch tuning skills with this information. In order to take it to the next level, there's a lot more involve. More information to come in the future!

[sleeper06]

I got 113 passes outta my last clutch on my bike with a relatively stock inner an outer but my boys drag ported cub wasted a clutch in 10 passes on the same track

[SlowerThanYou]

I firmly believe with spoon feeding you learn nothing. You need to feed yourself to actually learn/comprehend what's going on.

 

Wheelman, after reading my last post I hope you didn't think I was implying the above statement to you.

 

There was some information that I left out of this thread that I would consider spoon feeding. I didn't cover any specific spring pressures (base/static). Plus, I didn't cover any arm weights numbers. I left out some other things also.

 

Now, we have covered the lock-up itself, a few examples/scenerios. where to find some of the information, some hints & probably some other things that I forgot, that was covered. If there was some questions/areas that was not covered well/need more explanation, ask away.

 

The next area dealing with clutch tuning is the clutch pack (frictions & steels). How's this important & how does it affect the lock-up itself or overall clutch tuning? Maybe Wheelman (Chris) has some thoughts on this. Sorry to put you on the spot, LOL!

[m671054]

Since we are moving to the pack itself answer this please. What is the reason or when would you double stack steels and frictions. Example going from a 7 disc 14 friction surface down to a 10-12 friction surface. Would this only be for trying to control wheel spin on really loose surfaces??

[SlowerThanYou]

Since we are moving to the pack itself answer this please. What is the reason or when would you double stack steels and frictions. Example going from a 7 disc 14 friction surface down to a 10-12 friction surface. Would this only be for trying to control wheel spin on really loose surfaces??

 

IMO there's no need to double stack steels & frictions. We accomplish our slip with springs. The motorcycle guys used to do that & maybe even a few still do. It's a different way of getting slip.

 

Yes, it would help with wheel spin. The clutch is not the cure all for all situations. It's usually the first place I go depending on the situation. We would also look at changing a few other areas also.

[m671054]

Is it true that with a hinson spring basket you can run 7 or 8 plates? Was wondering as stck height would change by a fair amount thus lessening base pressure. Might be helpfull if the spring set i have is stll to tight when i'm at the dunes. As long as we are heading into the pack itself, are there large differences in steels and frictions in regaurds to thickness only??if you want to would you rank different brand frictions for longevity. Currently i just buy a couple of cheap sets a bring extras

[SlowerThanYou]

Is it true that with a hinson spring basket you can run 7 or 8 plates? Was wondering as stck height would change by a fair amount thus lessening base pressure. Might be helpfull if the spring set i have is stll to tight when i'm at the dunes. As long as we are heading into the pack itself, are there large differences in steels and frictions in regaurds to thickness only??if you want to would you rank different brand frictions for longevity. Currently i just buy a couple of cheap sets a bring extras

 

I don't know if you can run 7 or 8 plates in the Hinson.

 

Stack hieght does affect base pressure & it can be measured in lbs. We keep our stack hieght within a certain range, depending on different factors.

 

Here's one example: we change our stack height for the different tree speeds, .400 pro light or .500 full tree. That leads to your question of different thickness steels. We change our stack height with the steels up to .016. Give or take a few thousands one way or another.

 

As for the different thickness frictions. We start with the .118 thickness roughly & keep track as it wears down. We then use a combination of frictions & steels to adjust our total stack height.

 

As for ranking the frictions. We have only ran 4 different types & sometimes mixed in the pack. The way we set-up the clutch we only buy the better frictions. Our current YZF1000 fibers have around 200 runs on them. They are getting ready to retire soon. They are still working good, but not at their peak!

[Wheelman Chassis]

Wheelman, after reading my last post I hope you didn't think I was implying the above statement to you.

 

There was some information that I left out of this thread that I would consider spoon feeding. I didn't cover any specific spring pressures (base/static). Plus, I didn't cover any arm weights numbers. I left out some other things also.

 

Now, we have covered the lock-up itself, a few examples/scenerios. where to find some of the information, some hints & probably some other things that I forgot, that was covered. If there was some questions/areas that was not covered well/need more explanation, ask away.

 

The next area dealing with clutch tuning is the clutch pack (frictions & steels). How's this important & how does it affect the lock-up itself or overall clutch tuning? Maybe Wheelman (Chris) has some thoughts on this. Sorry to put you on the spot, LOL!

As far as clutches and steels go, I personally like to stay with the same fibers always. Any tuning i do as far as steels go is strictly thicknes and finish based. (finish of the steels can be altered for diffrent outcomes) but are very minimal in my experiance. (I also get into cutting the O.D of the steels on the inner most of the stack up) Ill explain in further discussion.

In my experiance, I have good luck tuning fine increments with the pack stack-up height. With that being said to help you guys just a little bit, as the clutch pack ht. gets taller the pressure plate will come to rest at a shorted installed height as far as the spring goes. This change in the height increases the static/base weight that is applied to the clutches.

The air gap in the clutch can also be used to effect clutch tune-up,but i hope brian will shed his own light on all this before i say any more lol

 

This knowledge can be very helpful after the clutch starts to wear. I try to map out my springs in .005 increments,so as the clutch wears i can add base pressure to compensate for a taller spring installed height. This will help you be a more consistant racer come the final rounds of elimination..

 

Hope this gets us rolling a little bit....

 

Great thread...

 

Chris

WheelmanChassis

[SlowerThanYou]

As far as clutches and steels go, I personally like to stay with the same fibers always. Any tuning i do as far as steels go is strictly thicknes and finish based. (finish of the steels can be altered for diffrent outcomes) but are very minimal in my experiance. (I also get into cutting the O.D of the steels on the inner most of the stack up) Ill explain in further discussion.

In my experiance, I have good luck tuning fine increments with the pack stack-up height. With that being said to help you guys just a little bit, as the clutch pack ht. gets taller the pressure plate will come to rest at a shorted installed height as far as the spring goes. This change in the height increases the static/base weight that is applied to the clutches.

The air gap in the clutch can also be used to effect clutch tune-up,but i hope brian will shed his own light on all this before i say any more lol

 

This knowledge can be very helpful after the clutch starts to wear. I try to map out my springs in .005 increments,so as the clutch wears i can add base pressure to compensate for a taller spring installed height. This will help you be a more consistant racer come the final rounds of elimination..

 

Hope this gets us rolling a little bit....

 

Great thread...

 

Chris

WheelmanChassis

 

We generally don't mix different fibers, but we have done for testing purposes/durability. As for different steels we mix all the time. Some cryod treated, some hard coated (not all coatings are the same), and different thicknesses.

 

A lot of what we do in the clutch pack is for durability, cooling, consistency & general inspection/maintenance. Is there performance gains also? you bet. Some not always related to ET. I already gave an example. You can have a killer fast clutch set-up, but if it's only good for 1 or two rounds. That will not usually win you a race. Everything has to stay some what consistent in the set-up, as with the rest of the quad set-up.

 

I thought I covered the airgap, but maybe I didn't. Air gap is measured between the lock-up arm & the pressure plate. The arm needs to be parallell to the plate surface when measured. lI will start with the minimum & it's usually around .090 - .100. Thats usually what you need to have the pressure plate totally disengage the clutch pack. The air gap will get larger as the clutch pack wears.

 

Enough for now.