Set me straight on Helix angles


I really do appreciate all the advice here. The first thing i am doing is go and pick up a digital gram scale so i verify the true weight of what i am going to be using.

For now until i can find a set of 8BU-10s is try the 8BU-00 since i am getting them and other stuff for free.

So what i am going to try first is leave my secondary basically the same with the 53/47 and green spring but move it to 70deg.....use the 8BU-00s with 2.7g heel and 3.6g tip plus the 48.7 of the weight itself giving me 55g on paper and the WWW primary spring. I will weigh the parts first before i install any rivets.

What do think of that set up as a first attempt?
 
will not work .....................................im sure u will underrave big time...and don't know why the gram on the paper are not accurate ....
 
Well, my sled is currently over reving at 9000rpms with the 8DN-20s loaded with 4.5g/5.0g plus weight= 51.59 grams right now. I do understand the 8BU-00 are more agressive so i was thinking of starting with both holes empty and see what is does but i wasn't sure because the weight itself is only 48.7g.

I assumed when Tony said to get a grams scale he has been down this road before with the accuracy of weights and rivets.
 
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yep u need a grams scale thats a must ....the profile of the weigh change things keeping the same helix ....you can get those grams scales for nothing on ebays ..been there done that
 
ReaperSRX said:
Well, my sled is currently over reving at 9000rpms with the 8DN-20s loaded with 4.5g/5.0g plus weight= 51.59 grams right now. I do understand the 8BU-00 are more agressive so i was thinking of starting with both holes empty and see what is does but i wasn't sure because the weight itself is only 48.7g.

I assumed when Tony said to get a grams scale he has been down this road before with the accuracy of weights and rivets.
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u do have a strong motor to run over 51 gram ;)!
 
REAPER YOUR NOT OVER REVING A LITTLE, THIS SLED IS OVER 500 RPM. WAY TOO HIGH HERE. I THINK THE STARTING POINT YOU POSTED HERE FOR 8BU-00 IS GOOD, ALTHOUGH I WOULD LIKE TO SEE YA CUT THAT 53 BACK ON YOUR INITIAL SHIFT ESPECIALLY WITH THESE WEIGHTS, THEY ARE VERY AGGRESSIVE. AND YES NO PAPER HERE, GET A GRAM SCALE. LIKE I POSTED, THIS IS NOT THAT BIG A DEAL, PRIMARY NEEDS WEIGHT, THAT SIMPLE. THIS IS ONE I ALWAYS GO BY WITH A OVER REV.
150 OVER TARGET- SECONDARY LOCATION
250 OVER TARGET- HELIX, SECONDARY LOCATION, GEARING
300 OVER TARGET- BETTER GET INTO PRIMARY, WEIGHTS, SPRING, ROLLER, etc. 3:16(YAMMIE TONY)
 
I am sorry, but that really PISSES me off when they won't even sell/ship to Canada. Just throw them in the mail, airmail and i don't mind the 10 day wait!!!!

Anybody on here in the US willing to work something out i can pay you directly andn you buy them then mail them to me?
 
ReaperSRX said:
I am sorry, but that really PISSES me off when they won't even sell/ship to Canada. Just throw them in the mail, airmail and i don't mind the 10 day wait!!!!

Anybody on here in the US willing to work something out i can pay you directly andn you buy them then mail them to me?
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im in same situation loll :o|
 
8bu-10

if you want those reaper, pm me and I will buy them and send them to you, not a big deal, the cost on them new is $32.48 each-$97.44/3 so youd get all 3 that way for $62.00 plus whatever shipping is to you(shouldnt be very much on that)
 
I just learned a few days ago that the steeper the finish angle on the helix, the less RPM's you will pull. Shallow finish angle will increase RPM's.
 
?? so will a steeper start angle lower your shift RPM's and cause clutches to upshift faster?


I am also guess that the reason that a shallow finish angle in needed with HC's is because there is a lot of mass in those weights both heel and toe which cause it to pull harder and up shift quicker?
 
Well don't think i will get much testing done this weekend, we are still getting snow and should get about 10" when it's done so there won't be too much hardpack to test on, i am just going to adjust my secondary a bit and just ride on Saturday and fish on Sunday with the kids, Saturday going to be cold though -28 for the morning without the windchill :brr

I will get the parts and digital scale tomorrow morning and see what's all in the box and go from there. Until i can find some 8BU-10s i will play with 8BU-00 for now.

Cheers and everybody stay safe on the trails!
 
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clutching

ive set up some srxs and viper i had one viper that no matter how much weight i put in the weight it still turned 8900 rpm i put a pin kit in to use cat weights more consistant shift curve then matched the rear with a green spring and a 51-43 rear helix geared down it worked great.i have always had trouble getting a yamaha weight to do want i wanted.just not enough experience with them or no time to fiddle around.i always found the lighter spring and lighter weight worked better for me less rotating mass.
 
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