EricMichael
New member
anyone know the how much 1 gram of rivet weight effects rpms? i'm trying to tune in my rpms I started with 8dn-20's. I was thinking maybe 1-gram= 100 rpm?
triple
New member
Do tell......
1 gram make 100 rpm drop
triple
New member
I'm new to the primary adjustments, can someone post a pic of what you end up adding/removing on the clutch? I need to drop about 4 grams and need a starting point.
change_up
New member
That's 1 gram total in all three weights just so you know... not 1 gram in each weight, that would lower rpms by somewhere between 300-400. I have always found that 1 gram seems to make just over 100 rpm diffference, but it's very close.
EricMichael
New member
change_up said:
really? so adding a .8 rivet to each weight will decrease rpms by 100 rpm ruffely? it seems i've added something like 3.6 to each weight before and it never lowered it 900 rpms that seems a bit much...
EricMichael
New member
I guess I still dont understand..say i'm trying to figure out my hole-shot rpms I want my sled to turn 8700 then climb to 8800-8900 the top rpms are good but its going right to 8,800-9,000 and staying there..I would say the tip weight is good how to do you go about splitting 1 gram to the inner between 3 weights??
Unanswerable
This question can not be answered for a few reasons. First of all, the location of the rivet in the weight makes a difference. It takes less weight out toward the tip to make a difference then it does closer to the heel. Secondly, the RPM of the clutch has an effect on the weight.....it takes less weight on a high RPM motor then it does on a low RPM motor to make a difference (centrifical force). It would be easier to let us know exactly what you are trying to accomplish and exactly what you are running, then people could make suggestions. Too many variables here to ba able to say that 1 gram equals 100RPM's. Sorry.
Madmatt
This question can not be answered for a few reasons. First of all, the location of the rivet in the weight makes a difference. It takes less weight out toward the tip to make a difference then it does closer to the heel. Secondly, the RPM of the clutch has an effect on the weight.....it takes less weight on a high RPM motor then it does on a low RPM motor to make a difference (centrifical force). It would be easier to let us know exactly what you are trying to accomplish and exactly what you are running, then people could make suggestions. Too many variables here to ba able to say that 1 gram equals 100RPM's. Sorry.
Madmatt
Read it again
OK, I read your last post a few times again. Sounds like you need more heel weight. Add a gram or so TO EACH WEIGHT. Or improve your traction, or, if you have enough traction get a helix with a steeper starting angle to shift it a little harder early. You might even try a primary spring with a little lower engagement RPM. What is your current set-up? Maybe we can help get you dialed.
Madmatt
OK, I read your last post a few times again. Sounds like you need more heel weight. Add a gram or so TO EACH WEIGHT. Or improve your traction, or, if you have enough traction get a helix with a steeper starting angle to shift it a little harder early. You might even try a primary spring with a little lower engagement RPM. What is your current set-up? Maybe we can help get you dialed.
Madmatt
EricMichael
New member
i'm going to be improving my traction in a couple weeks by adding 1-1/4 shot gun. Probably wouldn't be wise to clutch it for hte track that is on there now. Current set up in 8dn-20's with 4.5 tip inner empty..green sec. wrapped at 60 turns 9100 on long run. oh and a 51/43 helix..thanks for your help madmatt
Ya,thanks for the info
Try adding a gram or so to the inside hole in the weight (thats one gram in each weight) and your problem might be solved. Also, you might try experimanting with a red spring in that secondary. As long as it doesn't compromise your backshift it will probably let the secondary shift a little quicker. In my opinion less spring tension in the secondary is better as long as it doesn't suck the belt off the line and you have the backshift you want. Remember, try one thing at a time, then test. That being said, you might want to try the red secondary spring first since it will be an easier change. If that doesn't work, then put the green back in the secondary and add some weight to the primary in that inner hole. What primary spring are you using?
Madmatt
Try adding a gram or so to the inside hole in the weight (thats one gram in each weight) and your problem might be solved. Also, you might try experimanting with a red spring in that secondary. As long as it doesn't compromise your backshift it will probably let the secondary shift a little quicker. In my opinion less spring tension in the secondary is better as long as it doesn't suck the belt off the line and you have the backshift you want. Remember, try one thing at a time, then test. That being said, you might want to try the red secondary spring first since it will be an easier change. If that doesn't work, then put the green back in the secondary and add some weight to the primary in that inner hole. What primary spring are you using?
Madmatt
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EricMichael
New member
thanks for your help madmatt. its well apprieciated. I'm using a hauck orange..I have a gwg which might work better..i dont have much time to read up on things as i dont have a computer at home so its nice to have someone pointing me in the right direction so when i do bring it in i have a better chance of it working. The closest to a gram would be .8 for the yamaha rivets..i'll try that after i install my track..I read somewhere on here the slp pipe vipers like 3.6 inner and 3.6 outter..maybe that would be worth a shot?
EricMichael
New member
also, I was thinking that the sled even without any rivet weight may only be able to turn 9100 rpms period, if so I could possibly add more weight than expected to bring it down..I added a torque arm this year so maybe that is messing iwth it..i'm really not sure..