jhawker670
New member
Just went for a rip on sled. With the 48/36 helix the sled pulls the same top RPM (8500) at 92 MPH on speedo, slightly faster than before. This is with the same weight in primary as before, (my weights have not came in the mail yet) So If i add weight as mr viper suggests wont this pull my rpm down? I think I want to be 8500-8700.
J
J
staggs65
Moderator
That is quite odd that you'd pull the same rpm with a 36 as you did with the 47
jhawker670
New member
Yup thats what i thought, but went out again tonight and pulls 8500 rpm. Seems to pull a little better on top. When I put the helix in, I thought I would measure the spring that was in there and it measures 2.950. The Yammie service manual says 2.736 free limit. I did order a new secandary spring too but not here yet. I will change when it gets here. Dont know if that would be an issue or??
Did you mark your clutches and check the marks after a run? Did you check the bushings in the secondary? I have to think that you are not shifting all the way out if you really have stock gearing in there.
I thought you said you had heel clicker weights,but your now waiting for them to come in the mail?-confused by that statement...
what brand helix did you buy?
if all you changed was the helix and it runs the exact same rpm then the finish angle is not 36.
A 36degree to a 47degree will be a big rpm change if nothing else was changed alone, it would over rev if it was exactly at 8500rpm before, UNLESS something else was changed, or the helix is a 47 finish angle as before.
jhawker670
New member
Viper I do have heel clickers, but you said I need to add wait to heel, middle and tip so I had to buy more weights. Since I bought the sled used he didnt give me the extra weights he had. I bought the helix from ulmer racing. I asked him if he had a dalton helix48/36 and he checked and said yes and he sent it to me. It doesnt say a brand name on it. I gotta think it is NOT a TRUE 36 finish but that is stamped right on there. Exactly 8500 before and EXACTLY 8500 now.
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jhawker670
New member
ding,
I didnt mark anything yet till I get my extra hc weights in the mail. Will report back
I didnt mark anything yet till I get my extra hc weights in the mail. Will report back
thats pretty much impossible to have the same rpm with dropping the helix finish angle from 47 to 36, UNLESS you put it in at a differnt wrap on the sec spring or changed something in the set up from before, it just doesnt work that way.
That much of a finish angle drop would yield more rpm because its 11 degrees shallower. If you kept the sec spring tension exactly the same as it was with the 47 it would yeild likely 400-500rpm higher!
Only way you could keep the same rpm is if you changed the wrap on the sec spring to a lower tension.
You do know theres 3 differnt holes inside the clutch , plus the 4 spots on the outside of the helix.......
jhawker670
New member
viper I will check what twist i set it at. It was at 6-2 when I changed the helix. Yup I am aware of the holes.
Thanks
J
Thanks
J
jhawker670
New member
I just took the helix out of the machine and confirmed 6-2 angle.
staggs65
Moderator
The only other explanation would be what Ding was saying, something binding and not allowing full shift. That helix change was significant and should have yielded a change.
jhawker670
New member
yup will mark sheeves and run sled when it gets warmer than -36 here in mn.
mod-it
Member
I would think it isn't shifting out all the way. It has an 1-1/4" track and an M-10, and the original owner went a tooth more on the drive sprocket than stock...that would mean he geared it HIGHER instead of lower. With more track and the M-10 I would've wanted to go lower on the gearing, like maybe stay with the stock 22 on the drive and went to a 40 on the driven. I'm wondering if it is geared so high that it simple stops at 8500 rpm...but would be capable of quite a bit higher if it could actually pull the gearing correctly?? I'm far from a gearing/clutching guru like Ding and MrViper, but just my thoughts on it. I'm sure one of them can confirm if I'm way off base or not.
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jhawker670
New member
I am going to put a 22T sprocket back in and all of viper and Dings recommendations and see what happens. We finally got some warm weather coming end of week. I will report back after I run it.
J
J
jhawker670
New member
bushing on the helix is in good shape. the ramp shoes are like new. I dont think anything is binding. This guy took care of this machine like nothin ive ever seen.
jhawker670
New member
I got my extra weight set today form bender, I am not seeing how to arrive at 3.4 Grams in the middle hole with the heel clickers weights. Closest I can get is 3.3. Is that what you meant?
short bolt in middle, long bolt with 1 washer in tip.
they have changed the hardware over the years, some were 3.3. grams some were 3.4 grams, thats close enough, a tenth of a gram wont make any differance.........
they have changed the hardware over the years, some were 3.3. grams some were 3.4 grams, thats close enough, a tenth of a gram wont make any differance.........
jhawker670
New member
Ok. I got my heel clicker weights in primary. I did this with the clutch on machine. I just took the 6 bolts off the spider. How do the he11 do you compress that spring and start a bolt ? I got the heel clicker red spring.
jhawker670
New member
For some reason the red primary spring on my machine is way longer than the yamaha ones I see in the tech section. Is it normal for my red heel clicker spring to be so long?
Hammer Down
Member
I think yes. I just pulled a red spring out of a srx primary. With heel clicker setup. Longer than other springs I've seen