2008 M8 Helix question

[TheBreeze]

I am going to be doing most of my riding at 0-3000 ft. I still have the straight 36 helix installed, but cat recommends the 44/40 helix for low elevation. What type of performance differences will I see running the straight 36 at low elevation as opposed to the 44/40? Is there a better helix angle out there that will work well for both low and high altitude operation? Thanks in advance.

Matt

 

[Barrett]

44/40 w/ cat orange will work good at low elevation. strait 36 will not be as quick , but will probly feel just fine.
what are your expectations for a helix change?

 

[TheBreeze]

thanks for the response. I guess i am more interested in how a straight 36 will work at low elevation and how it would respond differently from the 44/40.

 

[Barrett]

strait 36 will be fine, it will maintain revs, and feel snappy, it just wont accellerate as quicky as a 44/40 - if the sled has the power to pull the steeper angle.

 

[Topogigo]

A 44-40 will upshift quicker and not backshift as well as a 36. The important thing here is to design your shift to opperate at the correct RPM. The sled may pull the 44-40 because you are opperating at low altitude and the sled makes more power. The 36 may over rev because of the same reason, this can be rectified by adding weight to the primary of the 36. Designing your clutching depends on the riding you plan to do. I hope this helps.

 

[killerrf]

i ran a 36 degree helix with cat orange secondary spring and shift assist in the secondary and 77 gram weights and yellow/green primary spring. rpms held rock solid at 7700. this is at 2200 ft.

i settled down to 80 gram weights and cat orange white primary spring then a 42/36 progressive helix with d&d gold secondary spring with shift assist for at home. ill use the secondary setup for at home and for the odd trip out to BC. just readjust primary for rpms. this is a '08 m8. 80 grams was the max for me though.