went back to 8DN-20's instead of HC's

bluemonster1

bluemonster1

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well I decided to install my spare clutch with the 8DN-20's loaded 5.5 grams in both holes.My helix is 51/43 wrapped at 70 at first,then tried 80.Same results with both settings.My belt height is adjusted dead on also.No squeal and track just moves ahead very slowly when up on stand.Put 85 miles on today and the clutches are nice and cool.The pull is still great.My engagement is around 3900-4000 rpm.If I pin it from a standstill ,she'll rev up quick.but seems to stall at about 7800.I let go of the throttle a second and pin it again and then she goes to 8500 plus.Now if i hold throttle to 3500 and pin it,it then revs right up to 8500.Got a pretty wild pull top end also.Only thing is that she is over reving to about 8800-8850 WOT.I got the sled up to 107 mph today with this over rev.With the HC's I couldn't get past 100.So 8DN's seem to be working.I have a green spring in the secondary.NOW how do I get that rpm down to 8500 WPT.Should I use a softer secondary spring,like a red spring.I should have one here,but have to look.Primary spring is now w-w-w spring.How can I now solve this over rev guys?
If I get sled tuned right,I may be selling the HC's to the best offer...we'll see.The triple motor is just humming today,love them tripples.
 
MONSTER I DON,T THINK YAMAHA HAS A LARGER RIVET THAN 5.5. I WOULD TRY THE RED SPRING AT 70 TWIST. ALSO, YOU NEED TO CUT FINISH ANGLE ON HELIX BACK. 50-40 I BET WOULD PUT YA SPOT ON. NOW THE BAD NEWS. I FOUND ANOTHER SET OF H/C. lol. 3:16 (yammie tony)
 
Dont you guys ever work out west ?It must be nice!I got tired of playing with rivots so i drilled the 8dns holes a little bigger to take the h\c t nuts and bolts with washers.They are hard to drill but not impossable.
 
so u think if i did like u switch to heel clicker my sled will be slower than before on top end .:-(((((((((( noooooooooooooooooooooooooo i hope not ... all that money for nothing tell me its a joke lollll... well nothing like trying my own stuff to see..
 
I didn't care for my 51/43 helix. Try putting the stock helix back on and see.
I could remember getting rivets from a Yamaha dealer who also sold I think John Deer products. They sent me steel rivets that they said they used on tractors. I don't know if they where used for tractors but they where steel perfect fit, cheap and heavy.
 
I put 2 washers at the end of the 4.5 and peened over them.Now they equal 5.5 grams.Did it last winter like that,had them sitting in the cupboard all this time.Now I put them back to use.
Bluewho.My Hc`s do not bind.Have clearance on them.Anyways..what bit did you use to drill out the Stock weights.You used a drill press right,but that steel is hard right.All I would do is just drill out the tip holes.Probably you didn`t have to enlarge them that great amount anyways.
 
My clutching book says 4.5g only. Hey monster what does the rpm jump to right away when you pin it? The reason I as is you could change primary springs but your rate will change. Your total shift pressure would change which would get you down. Could you try a ywy or a gwg primary spring?
 
yammigod...what would be the outcome if I put the 50:38 helix in place of the 51:43 helix,or for that matter the straight 47 helix.What would the outcomes be like you think..
 
don`t really know,I am not that clued in with clutching as others are.The only other spring I have is a y-g-y.Not sure about it`s rate.If I have 5.5 in tip now,realistically I would have to use maybe 7.5 grams to get it down.Why do sleds seem to over rev from factory anyways.Doesn`t make sence that Yamaha set it up that way.
 
if u switch helix u will overrave more on top or u will need to add some tip weight .. straigh 47 will work but will not be fast like the other one on start ...and u will need to fix again the tip weight
 
Because they don't want them to make peak power to stress them...Thats my opinion. Your ygy is about the same shift out force....When you pin it, what rpm right away???
 
I drilled out both holes yes the next size up.Than you can take the cover off on the lake and can adjust for porting or gear changes springs whatever. And dont have to fight with the big spring .Clutch bind from worn tower,plastic guides or cover bushing is what i meant there blue.One used clutch can perform better than the next one.I have seen h\c work awsome on a single pipe viper all around.There is nothing better at the track for D\R.
 
with what I have in now,I pin it and it goes to about 8500 or just a tad below.I did happen to find a y-w-y spring..the original SRX spring.So how would it help me with more force..by clamping down harder reduces rpm.
 
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