Wakegod
Pro
Does anybody have a clutching setup they are happy with for a supercharged Apex Mtn at 10lbs of boost or a turbo Apex at a similar boost level?
I'm stuck at about 57mph of track speed on a steep powder climb.
Running 10lbs of boost I know a similar turbo rx-1/apex will do high 60's or even 70ish. While I realize 70mph is probably unrealistic, I'd be pretty happy with mid 60's.
I get the occasional pull at 62-65mph, but seem to lack consistency as the clutches heat up. I even burned up a belt this past weekend tuning, in all fairness I think the belt was near the end of its life.
Current setup
8BU's, fully loaded with the heaviest Yamaha rivets. BPB primary spring.
Secondary: Shockwave at about 1.5 turns out, AC red spring at 30.
I plan on trying the silver secondary spring this week, as this setup worked great for my buddies turbo rx-1.
Another setup I have had ok success with
Stock weights with two homemade lead rivets in each weight, for a total of approx 88 grams. BPB primary.
Secondary: Same as above, sometimes slightly shallower helix and usually a little more spring twist.
What really bugs me is that it feels like my sled has gobs of power, but I don't seem to get the power to the snow. When it comes to a monster climb in powder I absolutely destroy all the 2 strokes we ride with, but in setup powder snow a drag race is closer than it seems like it should be.
Any suggestions are welcome
I'm stuck at about 57mph of track speed on a steep powder climb.
Running 10lbs of boost I know a similar turbo rx-1/apex will do high 60's or even 70ish. While I realize 70mph is probably unrealistic, I'd be pretty happy with mid 60's.
I get the occasional pull at 62-65mph, but seem to lack consistency as the clutches heat up. I even burned up a belt this past weekend tuning, in all fairness I think the belt was near the end of its life.
Current setup
8BU's, fully loaded with the heaviest Yamaha rivets. BPB primary spring.
Secondary: Shockwave at about 1.5 turns out, AC red spring at 30.
I plan on trying the silver secondary spring this week, as this setup worked great for my buddies turbo rx-1.
Another setup I have had ok success with
Stock weights with two homemade lead rivets in each weight, for a total of approx 88 grams. BPB primary.
Secondary: Same as above, sometimes slightly shallower helix and usually a little more spring twist.
What really bugs me is that it feels like my sled has gobs of power, but I don't seem to get the power to the snow. When it comes to a monster climb in powder I absolutely destroy all the 2 strokes we ride with, but in setup powder snow a drag race is closer than it seems like it should be.
Any suggestions are welcome
mulot30th
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- 2023 thundercat
apex mountain crracing 174
apex blower 136 for asphalt racing
osp drag race sled (apex engine based)
on 10 psi, with a 162x16x2.5 extreme track, I get around 60 to 65 mph track speed on my rx1 mtn (apex engine)
I am fighting with my clutching too and have 75 grams on 8fa weights and just started trying the shockwave last weekend at 1 1/2 turns out. In the 4' of fresh I was only pulling 9000 rpm. Seems I am running too much weight according to MPI. I am clutching for 10k feet.
Wakegod
Pro
mtnxr said:
Why are you running 8fa's? Is this on an Rx-1?
Do you have the 14.5mm rollers in the primary? These, more than any other change I made clutching wise seemed to lessen the engine braking, which was a huge plus for me.
I bet 8bu's fully loaded or Apex weights (8FP) with a heavier mid rivet would work great at your elevation.
What secondary spring are you running in the shockwave?
My setup I settled on from last weekend
Primary:
8FP with 9 gram lead rivet (homemade) in heel and mid, with a 4.5gram steel rivet in the tip.
14.5mm rollers.
Blue pink blue primary spring, although I may go to BSB, or even WSW to pick up a few rpm on engagement and up on the hill in powder.
Secondary:
AC Red spring at 30. Shockwave 1.5 turns out.
I pull 58mph with skis on snow in powder and as I start to wheelie out of snow I pickup to 62-65mph on a steep climb. 10,400rpm, so I could stand to pickup a few rpm, hence the thought of a WSW primary.
The setup was from High Altitude Boost and is loaded 8fa weights with ypy spring, 45-47 helix and white spring, stock rollers. I have no idea what speed I carry climbing but I get pretty big swings in RPM so I know it's not right. I think I am headed for 8fs load heal and center bpb spring and go from there. What made you decide to run the 8bu weights?
Wakegod
Pro
mtnxr said:
I tried the 8bu's on the advice of my riding buddy Spray. He had a turbo rx-1 with an 8bu setup that he really liked. I did like the 8bu's in the sense that the power was extremely snappy, but I didn't like the super high engagement (4300rpm which I could of tuned a bit) for boondocking, and it seemed like it was always just revving super high to go anywhere compared to my 8fs setup. Also, I've never blown a belt except with the 8bu setups I tried.
That makes sense....I have a buddy with a turbo and that is the setup he runs with a 8bu w/bpb spring and a 51 helix with a crazy tight springs. I think the lighter weights and higher engagement work with the little bit of lag with the turbo. I am going to try this new setup and will let you know what I think.
