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Does it have to be in lock up mode?
Have you tried to set up in slider mode and get an idea of what it is capable of running?
 

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to much launch rpm i have a mtc gen 2 put it in out of the box on a stock motor 1000 leaving about 4500-5000 and it will 60 low 1.40s all day long with some tweeking it will go better just my 2 cents good luck
 

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According to your graph your 2 step is too high compared to your clutch engagment.

Your clutch is coming in around 6900, you should be holding a few hundred under that or raise the clutch rpm with stiffer springs. Let the rpm run into the clutch, not the other way around. That's where I'd start. Another thing to look at is when the 2 step disengages relative to the clutch engagment at the lever. You want to have the 2 step come off a little in advance.
 

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to work @ 64" on a 2-step and not wheelie i would think 6,000 rpm in multi-stage mode or setup it up a little lower rpm in slider mode. that chassis setup will 1.3 something @ best. No experience in slider mode but in multistage mode i would think a stock motor would use less than 60lbs static and minimal arms and minimal weight. possibly aluminum nuts and bolts to get weight below 5g
 

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i have a Hayes 3 fingered set up and in convertable slider mode, leaving around 6300-6400 i was getting low 1.3 60ft's
 

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Take some static out of it(leave enough static in it to ride it back), and try leaving at dead idle like the mathews brothers said. It sounds crazy, but it works. I kept trying to leave at a high rpm but the motor kept bogging, i took their advice and it works like a charm.
 

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Discussion Starter · #29 ·

Well I opened the cover and threw in some light weight springs and sure enough its engaging at right around 6000RPM. Im now wondering what I can do to get it to engage at a higher RPM. I have the stiffest springs in it right now and at 6K it all begins. Im going to try launching at 6000 and see if my 60 improves but I know that my power doesnt really start to come in until 8500 or so. Thats why Id like to raise the RPM in which it engages. What do you think?

Here is my setup:

View attachment 78260
 

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i would add more gear also try 15-46. that will help you out once the clutch is tuned, ive been 1.36 60ft on a 07 gsxr 1000 with 15-48 they love lots of gear, stock clutch, you can run through the 1/4 with the 15-46
 

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i have a bone stock motor in my bike and my 60ft 1.6s if i don't use NOS i let someone else set my clutch up for me and i leave at 3500rpm on
 

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Thanks John. Top Hole or bottom to start. They are a pain in the ass to get the 3 springs in and out LOL.
Do you have the black arms that are called REV3? they are much easier to get the springs in and out of. They are a little different ratio as well, but worth a try.

If your goal is to try to delay the engagement, you will want to remove weight or increase outer spring force.

If you install taller gearing, the bike will also tend to slip a bit longer, although for a different reason. The clutch will have more load on it in order to engage with taller gearing, making it slip more even though the arms are "coming in" at the same RPM (they will need to "come in" harder in order to transmit the torque required to prevent slippage with taller gearing, making the clutch slip for a bit longer.)

With your setup, I doubt you are making much torque, and you may want to remove some more static to let it slip to get the revs up.

The amount of torque the clutch will transit is based on the TOTAL amount of force on the pressure plate. The fibers and steels don't know if it is coming from static springs or the dynamic arms. The static springs pretty much apply the same force all of the time, while the dynamic arm force is RPM and weight based.

Increasing the air gap can also change the engagement of the clutch. It slightly lowers the force of the static springs, due to compressing the springs, as well as slightly increasing the RPM at which the dynamic arms engage, due to them having to move farther (and stretch the extension spring farther) to engage.

That said, once the arms do contact the pressure plate buttons with the larger air gap and start applying force, the rate of increase of the force due to RPM will be slightly higher because the arms will be slightly farther away from the center of your clutch basket, making them exert more force from the rotation.
 

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Discussion Starter · #35 ·
Do you have the black arms that are called REV3? they are much easier to get the springs in and out of. They are a little different ratio as well, but worth a try.

If your goal is to try to delay the engagement, you will want to remove weight or increase outer spring force.

If you install taller gearing, the bike will also tend to slip a bit longer, although for a different reason. The clutch will have more load on it in order to engage with taller gearing, making it slip more even though the arms are "coming in" at the same RPM (they will need to "come in" harder in order to transmit the torque required to prevent slippage with taller gearing, making the clutch slip for a bit longer.)

With your setup, I doubt you are making much torque, and you may want to remove some more static to let it slip to get the revs up.

The amount of torque the clutch will transit is based on the TOTAL amount of force on the pressure plate. The fibers and steels don't know if it is coming from static springs or the dynamic arms. The static springs pretty much apply the same force all of the time, while the dynamic arm force is RPM and weight based.

Increasing the air gap can also change the engagement of the clutch. It slightly lowers the force of the static springs, due to compressing the springs, as well as slightly increasing the RPM at which the dynamic arms engage, due to them having to move farther (and stretch the extension spring farther) to engage.

That said, once the arms do contact the pressure plate buttons with the larger air gap and start applying force, the rate of increase of the force due to RPM will be slightly higher because the arms will be slightly farther away from the center of your clutch basket, making them exert more force from the rotation.
You are the fuggin man:beer:I appreciate the great explaination:2thumbs: Im going to try the three arm setup and begin with the upper holes. I dont have the REV3 right now but I am looking into it for next season. Looks like I have 1 weekend left this season to test hence the reason why Im really trying to figure this out now. Thanks for the direction and I will be sure to post up where I end up.

Josh
 

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Discussion Starter · #37 ·
I made it out this weekend and made 7 passes. Started with changing the static springs so I could barely ride it back to the pits and after 3 passes with differing setups I made it back to a 9.31 at 144mph. So I went over to using 3 arms with 3 springs and platyed with the weigh and made it back down to a 9.32 at 145mph but the best 60 of the day was a 1.52. man this is getting old. Motor still boggs out of the hole no matter what I do. Ive change the launch RPM, arm configuration, weight etc...even started playing with the extension springs. I have gotten the motor to only drop 200-300 rpm on launch but it takes forever to recover. After that the bikes flying. Even had one pass that it did not bog but just took forever to get the RPM moving up. I then took more weight off and it completely blew through the clutch. I think that I may need to go back to using 6 arms and learning what springs come in at what rate ie. 2 arms for 6-8000, then 2 arms for 8-10000 then the last 2 for 10-13000. And just leave the static so I can ride it back. I also found that when I launched from 6000 it would race up to 10k then bog and the reaction time was terrible.

View attachment 78348
 

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Are you saying this is a Bog? What am I missing? Doesn't look like it bogged at all, continually climbing.

Or is it teh 6000 to ~200 drop just to the left of the vertical line that you are referring to? Seems odd that there is zero wheel speed when the motor drops from 6000 to 2000.

To me it looks liek you cleaned the motor out to 6000 rpm at ~218.75sec, Then free revved it to ~ 2000 rpm, then left. RPM then jumped to ~ 8900, then rose to ~9200 during the clutch engagement, then the clutch locked right at 222 sec (after the 60'), and the bike continued to ~13,200 shift point.
 

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Discussion Starter · #39 ·
No bog here...this was the only pass that didnt do it. The 6000~2000 was me on the 2 step and because Im using the ECU Editor and I am tied into the coil (or injector...cant remember which one for the SL-1) it never shows the actual RPM on the 2 step that is what you are seeing there. That being said I cant get the 60 anywhere into the 1.4 or less range. I know its possible because I did it with the hand clutch and it seems like nothing I do gets the 60 any better. I believe if memory serves me I was able to do it when I first got it but I found out that I had a different year inner hub in it then it was supposed to have and i was running only 2 vs the stock 4 bellvue spring washers behind the inner that ride on the clutch mod. I think im going to pull the 2 back out adn see if thats hurting the engagement of the clutch. Not sure what else to do so Im grasping.LOL
 
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