Sunday Feb 22 we did some clutch testing at Mr Sled's. The results were an improvement, but still not a cure for my issues so we press on.
Ulmer prescribed kit= Red spring 6-2 with Ulmer K helix and 50Y with 1T 2W heel plus 1W tip is what I started with. RPM's were definitely low. Low 8k's building to about 8500-8600.
Pink spring 6-1 shimmed with Ulmer K helix This seemed to accelerate faster as speeds crossed 80 mph. RPM's seemed to come up through the mid better.
We ended up unloading the weights to get RPM up. First the tip then the heel one washer at a time and we did come across 90 mph. Final weight config is 50Y with 1T in the heel. RPM is still a bit inconsistent, but climbed to the 8800-8900 range.
We left it there and I rode this past Saturday the 28th and Sunday March 1 with this config. It definitely pulls hard right through the 70's and across 80 mph much better now hitting 86-88 mph regularly in decent trail conditions. What I found lacking though was the "hit" out of the hole. It does not wheelie or arm pull like it did with the initial config.
Sunday March 1 I stopped by MrSled's once again and borrowed his Ulmer H helix at Allen's suggestion. Conditions were questionable so I could not really get good top speed out of it. It popped 90-91 at one point, but consistently crossed to 86-88 mph as before. RPM's are up and seemingly more consistent especially in the mid range. It now runs 8800-8900 even 9000. Primary still slipping on top end.
So with what we have changed it "feels" faster, but what it is lacking is the hit out of the hole. I put the 2 washers back in the heel. This helped with tapping the limiter on a launch with spinning. Still did not wheelie and stretch arms like it used to.
Back to Ulmer red spring at 6-2 wrap. Wheelie is back as is arm stretching. Thing I noticed though is that my downfield speed is less. The pink at 6-1 I was having trouble stopping. The speed was sneaky and continued to build. I was hitting 77 mph with the pink and 75 with the red. The acceleration of the red was a bit more boring and seemed to flatten out and the pink I was having stopping issues as it seemed to just keep pulling. I did not have time to drop back the wind on the red spring to se what it did.
What was puzzling me during my testing was how the sled was seemingly faster yet was not stretching my arms nor was I having as much difficulty with the sled veering to the side.
About all I can guess is that the arm stretch of the Red 6-2 may just be hooking up better and the fast feel of the pink 6-1 is spinning a bit more but maybe actually faster? But how can less arm pull be faster? More linear I guess?
Ulmer prescribed kit= Red spring 6-2 with Ulmer K helix and 50Y with 1T 2W heel plus 1W tip is what I started with. RPM's were definitely low. Low 8k's building to about 8500-8600.
Pink spring 6-1 shimmed with Ulmer K helix This seemed to accelerate faster as speeds crossed 80 mph. RPM's seemed to come up through the mid better.
We ended up unloading the weights to get RPM up. First the tip then the heel one washer at a time and we did come across 90 mph. Final weight config is 50Y with 1T in the heel. RPM is still a bit inconsistent, but climbed to the 8800-8900 range.
We left it there and I rode this past Saturday the 28th and Sunday March 1 with this config. It definitely pulls hard right through the 70's and across 80 mph much better now hitting 86-88 mph regularly in decent trail conditions. What I found lacking though was the "hit" out of the hole. It does not wheelie or arm pull like it did with the initial config.
Sunday March 1 I stopped by MrSled's once again and borrowed his Ulmer H helix at Allen's suggestion. Conditions were questionable so I could not really get good top speed out of it. It popped 90-91 at one point, but consistently crossed to 86-88 mph as before. RPM's are up and seemingly more consistent especially in the mid range. It now runs 8800-8900 even 9000. Primary still slipping on top end.
So with what we have changed it "feels" faster, but what it is lacking is the hit out of the hole. I put the 2 washers back in the heel. This helped with tapping the limiter on a launch with spinning. Still did not wheelie and stretch arms like it used to.
Back to Ulmer red spring at 6-2 wrap. Wheelie is back as is arm stretching. Thing I noticed though is that my downfield speed is less. The pink at 6-1 I was having trouble stopping. The speed was sneaky and continued to build. I was hitting 77 mph with the pink and 75 with the red. The acceleration of the red was a bit more boring and seemed to flatten out and the pink I was having stopping issues as it seemed to just keep pulling. I did not have time to drop back the wind on the red spring to se what it did.
What was puzzling me during my testing was how the sled was seemingly faster yet was not stretching my arms nor was I having as much difficulty with the sled veering to the side.
About all I can guess is that the arm stretch of the Red 6-2 may just be hooking up better and the fast feel of the pink 6-1 is spinning a bit more but maybe actually faster? But how can less arm pull be faster? More linear I guess?
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