Thunder products

[cannondale27]

I'm assuming you didn't get the hardware kit with the purchase of the sled.....

If you did receive the hardware kit, I would take the 3/8 steel and thick washer out from the tip and put in a 3/8 aluminum with a thin washer in the middle and the tip . Try that first.

The midnight blue spring is made for the kit you have. You can twist that spring up to 6-2 to keep your top rpm's up also.

Like I said i'm new to clutching and trying to understand what does what. At this point I've had people tell me to take weight off and leave the spring, others have said at that weight I need a heavier spring. I'm just trying to make sense of everything and figure out whats the right way to get things working. The guy that said to go heavier spring didn't think enough weight could be removed to gain 800-1000 rpms? They currently have 8 or so grams that can be removed based on what my scale showed. 3.3 in the heal, .4 in the mid and 4 on the tip. The base weight is around 58 grams roughly. We don't have snow currently so I can't go out and test it without driving 4 hrs up into Michigan.

What Nos -Pro advised is a drastic change from what you have now. I dont know whether it will give you 800-1000rpms but I would think it would be alot. Do it and go rip up the yard or street. Wear a helmet!

 

[ricer68]

What Nos -Pro advised is a drastic change from what you have now. I dont know whether it will give you 800-1000rpms but I would think it would be alot. Do it and go rip up the yard or street. Wear a helmet!

I put it back together with the red dalton spring and weights set the same as before. I couldn’t get a good full pull but was able to get it to 8400 and some chance going across filter strip. The tack said max RPM was 9110 which I’m sure was on take off. The belt was hot when I got back to shop and could smell it. The primary was hotter then secondary. The secondary spring twist was 6/1

 

[cannondale27]

You are still way too low rpm on top. Do rollons till you get this figured out. Then you can use the Max Rpm feature and be confident in your results.

 

[cannondale27]

You also never mentioned what belt you are running and how your clutches look as far as dirt/rubber on them.

 

[ricer68]

You also never mentioned what belt you are running and how your clutches look as far as dirt/rubber on them.

They are clean, just had the primary apart and cleaned it. Wasn’t to bad. Rubber bumpers look good. Running gate carbon fiber belt. Not sure part number off top of my head.

 

[blueironranger]

Just noticed you have a Turbo, my phone didn’t show your signature, computer does. How is your boost? Might be a low boost issue instead of clutch issue.

 

[ricer68]

Gates 40c4340

 

[ricer68]

Just noticed you have a Turbo, my phone didn’t show your signature, computer does. How is your boost? Might be a low boost issue instead of clutch issue.

Just pulled my data logger. Boost ran between -8 and 6 maybe 7 psi

 

[ricer68]

I talked with MPI, they think its something in the clutching. Based on the boost and how it pulls to 60-65 MPH they think the engine and turbo is good.

 

[PeeWee86]

Just to be clear, I never believed or suggested that a spring change on its own would give you an 800+ rpm increase. I expected about 400 rpm. It sounds like you didn’t even see that much. I generally prefer higher rate primary springs and since you already owned the Dalton red I thought it would be a step in the right direction.

The mid shift rpm is approaching the rev limiter and that will be a concern as you start removing weight from the clutch arms. With a turbo you want to build rpm as quickly as possible without hitting the rev limiter during the initial shift. This helps to build boost pressure quickly.

If you stick with the Dalton red spring then I would only remove tip weight. Your other move would be to go back to the blue-silver-blue and follow Nos-Pro’s recommendations for removing weight from the clutch arms.

Every clutch set up you try will give you experience that you can build on going forward. Once again keep good notes.

 

[ricer68]

I’m going to go back to other spring and try nos’s weight suggestion. I can’t test any more. We have gotten warm and have rain and mud now. Hopefully I’ll get a chance to go north again and run some more. Just hard to work on it on side of trail. I did try putting my apex clutch on last night to see what it would do, seemed to rev higher. That would lead me to it being something with the primary. The Dalton spring worries me since the clutch and belt got warm with it. The secondary wasn’t as warm. It’s at 6/1 twist.

 

[shagman]

I’m going to go back to other spring and try nos’s weight suggestion. I can’t test any more. We have gotten warm and have rain and mud now. Hopefully I’ll get a chance to go north again and run some more. Just hard to work on it on side of trail. I did try putting my apex clutch on last night to see what it would do, seemed to rev higher. That would lead me to it being something with the primary. The Dalton spring worries me since the clutch and belt got warm with it. The secondary wasn’t as warm. It’s at 6/1 twist.

Something is definitely going on. Your original setup is lighter than I was running with my turbo viper. It should be close. Check over both clutches again.


Sent from my iPhone using Tapatalk

 

[ricer68]

Something is definitely going on. Your original setup is lighter than I was running with my turbo viper. It should be close. Check over both clutches again.


Sent from my iPhone using Tapatalk

I've had both clutches off and looked them over and can't seem to find anything wrong with them. Everything moves free like my apex clutches do. We are now mud so no testing until things freezes up or I can head north again.

 

[ricer68]

I put the weights like nos said and out the bsb spring back in we’ll see next time it snows. Hopefully this year.