helix/backshift/clutch?

M

mes882

New member
Joined
Dec 17, 2011
Messages
204
Age
49
Location
iowa
Here a little background info first
97 sx700 with reed stopper notch otherwise stock
In Iowa about a 1000ft.

primary
weights 8ch 4.5 inner (17.2 rivet) outer 3.6 (13.9 rivet)
stock spring wsw
rollers stock 15mm

secodary
green spring (stock)
set at 60 degrees
stock helix 45 degree with this helix sleds turns about 8800-8900
installed a straight Yamaha helix 47 degree set a 70 degrees sled turns about 8500-8600

track is 1 1/4 predator

belt is 89l

Clutches are in good shape and clean.

We do mostly groomed trail riding with the 47 degree helix at 70 degrees there is a lack of back-shift but 8500-8600 rpms. If I add more twist to improve the back-shift then you gain a few more wot rpms correct?

The 45 degree helix set at 60 degrees had plenty of back-shift but 8800-8900 rpms. I really cant believe the difference just between 2 degrees.

I guess what I am trying to accomplish is getting the wot r's down to that 8300-8400 mark. I could live with 8400-8600. I am sure the springs in the clutches are the original ones. I have 2 of these sleds both do the same thing. Both are set-up the same way. One has 2900 miles the other 3900 miles. O one still has the 8ch belt on it which is in good shape.

Would going back to the 45 degree helix and new springs be the cure all??? Thanks for your help.

Quick question about drilling out the silencer. Would that affect wot rpms at all?? Would I need to re-jet?? I think some one might have done the silencer mod on one of them. It is just a shade louder then the other one. Not much louder but enough you can noticed it. I should get a flashlight and look.
 

Do the 45 and a BRAND NEW spring. I know this might sound trivial, grab the Dremel w/ a polishing bonnet and some red Tripoli. Those ramps can easily be polished to mirror finish. You can get the finish pretty good with a polishing wheel attachment for the bench grinder. But it's the speed of the Dremel (35,000) that'll make it a "slippery slope".
No different jetting is required for boring the silencer.
 
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Ok I will order some new springs primary and secondary. I find it a little funny you said red Tripoli. I have never heard of the stuff and I live in a small town called Tripoli. I am assuming any aluminum polish would work?? I have some mothers that I use on the motorcycle.. Thanks.
 
I have been wondering about doing the rivets. Ok I will probably have to take it some where to do the rivets. Looks like I need to make a trip to Menard as well.
 
Just drill the rivet dead in the middle not sure what size then pop the head off with a chisel.
 
I am not sure about smashing them in with a hammer. I am guessing a shop has a nice little press to do it.
Man I just ordered 2 primary springs 90501-555j9-00 and 2 secondary springs 90508-556a2-00. They don't give those away.
 
smashing with a hammer on a vice is easy i used a 8lb mall choked my grip up by the head took very little skill. just a steady hand.
 
ok ok guys stop beating me up about it.:whine: You shammed me into it I just ordered some rivets 90261-06033-00. Not sure what to expect but I will give it a shot. I am more of a visual person. So what should the rivet look like when I am done. Maybe I am making more of this then what it is.

Ok so my game plan for now is install new secondary spring. Put the 45 degree helix back in set at 60 degrees. Then see where the rpm are at.

Then take out the weights and add 4.5g rivet in both holes along with a new primary spring. Then hopefully that will bring my rpm into check.

I also hope that the parts get here before the snow melts away.:letitsnow:letitsnow
 
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I believe you stated you have 4.5 in the inner already, so you only need to change one take a close look at that one and that's roughy what your installed one should look like. Just make sure you drill close to center so you can use a bit same or slightly smaller then the shank, use new rivet to find proper bit.
 
What would a 51/43 helix due to the rpms?? I know I would have quicker up shift and more back shift. Not sure how it would affect the wot rpms.
I am thinking I need to get the over rev taken care of with the stock set up before I mess with other things.
 
it will have an effect on rpm, but im not sure how much,every sled is a little different.could be 200 rpm on my sled, and 400 rpm on yours.the only way to know is to try it.but it will shift much more aggressive on the start.you will like this helix for sure.
 
Well I got my new springs today. I put the 45 degree helix back in and the new secondary spring set a 60. Well something is not right. I am just not sure what. I left the 47 in the other sled set at 70 it has little more back shift then the other one.:o|:o|
 
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