Ahhh OK. There is your problem you need a dual angle.
gabbett1
Member
Really? Why is that? I do know that the old setup (when it was an 800) was a straight helix. I guess I just don't know much about the helix and how to determine when you need a dual angle.
Also, just for clarity, when I said I wasn't reaching peak RPM it wasn't that there was bog or anything. The engine sounded great and it hit the RPM and held it. I just thought my weights were off. I haven't adjusted the primary since I discovered I had the wrong belt.
Straight angles are great for big high torque twin cylinders with a super wide flat power curve to clutch.
A piped high rpm triple has a narrow hard to clutch power band. So to keep it on the pipe at 9000 rpm you have to slow the upshift down (not so aggressive up top). The dual angle does just that. 51-49 will give you same characteristics down low but help hold the 9000 rpm up on top end.
A piped high rpm triple has a narrow hard to clutch power band. So to keep it on the pipe at 9000 rpm you have to slow the upshift down (not so aggressive up top). The dual angle does just that. 51-49 will give you same characteristics down low but help hold the 9000 rpm up on top end.
gabbett1
Member
Welcome to another year of sledding. So we have some early snow this year and I've been out doing some testing. I didn't change anything from last winter and wanted to get a baseline. I have a nice field I test in. We have about 4-6 inches of snow. I noticed that the sled will pull strong all the way up to about 80 and then stops accelerating. I decided to switch the yellow secondary spring to the blue one that you suggested last time. Went to test again, and same result. Climbs to 80 and stops going any faster. We have some nice snow/ice covered roads so I decided to take a couple passes on it. Roars up to 90 and is still climbing hard. So, for some reason my setup doesn't like any kind of snow at all. Seems to me that it still has to be something minor in the clutching but I'm not sure what it could be. Possibly if the helix is to aggressive? What are your thoughts?
If the helix is to aggressive...it will search for rpm on acceleration or pull the engine down to low and not accelerate properly.
To aggressive helix will have a lazy backshift as well when off/ on throttle.
Maybe you are running out of gear ratio? To low
To aggressive helix will have a lazy backshift as well when off/ on throttle.
Maybe you are running out of gear ratio? To low
gabbett1
Member
I don't think it's gear ratio. It's stock gears and stock you can get to 105mph. 78 mph is a far cry from 105. Plus remember that I'm hitting 90 and still accelerating hard on hard pack roads.
gabbett1
Member
Changed my 51 degree helix to a 52/48 (that's the only multi angle one I have). Picked up a few mph (in the field) and it seemed like it wanted to go a little more, but I ran out of room. Also noticed that the snow is pretty heavy/wet right now so that is probably holding me back as well. I would think this should have more than enough power to overcome, but maybe not.
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