Shifter adjustment
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Re: Shifter adjustment
No problem, Captain. I'd bet you are busier than a long tail cat in a room full of rocking chairs right about now. I'm happy that it works and willing to leave it at that. Its just in my "control freak and I want to know everything about everything" nature. I'll give it a go on a DS and see if I can get the hang of it. I just want to make sure I have the technique down.
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Re: Shifter adjustment
Matt,
I use the clutch almost all the time. Whether one needs to or not is a matter of style or opinion. You can down shift without using the clutch but the speed misalignment of contiguous gears is increased shifting down. It isn't worth risking damage in my opinion, and if the engagement balls are being fought by the next gear down, the increased pressure needed on the shift ball springs simply accelerates the fatigue of the spring if you don't use the clutch shifting down or if you don't get the engine speed right.
Ed, I didn't invent physics, and didn't invent helically wound springs, but a little research will show that there is nothing magical about Hodaka shift springs. All helically wound springs are subject to the same forces under compression. The idea that the "space aged" springs don't need to be counter wound or bottom ground came from the engineer guy that sold the idea to Paul. I simply don't agree with the guy, and I don't have any springs to sell, so there is no sales pitch here. Compression force on a helically wound spring directed on the axis of the spring center is translated down the helix on the axis of the wire from which it is wound. Helical springs under compression grow in girth because the wire is not compressible down its own axis. This translated force causing the spring to grow fatter under compression is a vectored force not parallel to the direction of compression on the spring. When shift springs fatigue they are most often "unwound" on the side nearest to the shift ball. If all force on a Hodaka shift spring is axial to the spring and shift shaft, why does the wire flare when fatigued?
There is also a momentary translated rotational force experienced while the shift ball assembly is moving from one gear to the next. Once engaged, the balls and springs are fairly stationary over the shift shaft because they are rotating at the same speed as the countershaft. But while traversing from gear to gear, there is a rotational differential due to two gears not rotating at the same speed as the countershaft. This would be why Hodaka engineers designed the springs as they did, counter-wound, bottom ground, and buffered with washers, and why the NASA guy is wrong about spring design. If you shift without the clutch, there is an increased abuse of the springs if you don't back off the power a bit, but as long as one understands that the springs don't last forever no matter how you shift, it is a matter of choice how you drive your bike. It isn't that the space aged springs don't work, it is that they attempt to use improved metallurgy to obviate an otherwise needed combination of design features. If they were made correctly out of the improved wire, they would be great. As it is they are acceptable more or less.
I use the clutch almost all the time. Whether one needs to or not is a matter of style or opinion. You can down shift without using the clutch but the speed misalignment of contiguous gears is increased shifting down. It isn't worth risking damage in my opinion, and if the engagement balls are being fought by the next gear down, the increased pressure needed on the shift ball springs simply accelerates the fatigue of the spring if you don't use the clutch shifting down or if you don't get the engine speed right.
Ed, I didn't invent physics, and didn't invent helically wound springs, but a little research will show that there is nothing magical about Hodaka shift springs. All helically wound springs are subject to the same forces under compression. The idea that the "space aged" springs don't need to be counter wound or bottom ground came from the engineer guy that sold the idea to Paul. I simply don't agree with the guy, and I don't have any springs to sell, so there is no sales pitch here. Compression force on a helically wound spring directed on the axis of the spring center is translated down the helix on the axis of the wire from which it is wound. Helical springs under compression grow in girth because the wire is not compressible down its own axis. This translated force causing the spring to grow fatter under compression is a vectored force not parallel to the direction of compression on the spring. When shift springs fatigue they are most often "unwound" on the side nearest to the shift ball. If all force on a Hodaka shift spring is axial to the spring and shift shaft, why does the wire flare when fatigued?
There is also a momentary translated rotational force experienced while the shift ball assembly is moving from one gear to the next. Once engaged, the balls and springs are fairly stationary over the shift shaft because they are rotating at the same speed as the countershaft. But while traversing from gear to gear, there is a rotational differential due to two gears not rotating at the same speed as the countershaft. This would be why Hodaka engineers designed the springs as they did, counter-wound, bottom ground, and buffered with washers, and why the NASA guy is wrong about spring design. If you shift without the clutch, there is an increased abuse of the springs if you don't back off the power a bit, but as long as one understands that the springs don't last forever no matter how you shift, it is a matter of choice how you drive your bike. It isn't that the space aged springs don't work, it is that they attempt to use improved metallurgy to obviate an otherwise needed combination of design features. If they were made correctly out of the improved wire, they would be great. As it is they are acceptable more or less.
Hydraulic Jack
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Re: Shifter adjustment
Hydraulic, it would be nifty if you would go to the bench and measure the linear displacement of the control shaft assembly required to complete a shift. Then measure the capacity of the OEM spring to absorb that movement, store the energy and complete the shift when the currently engaged gear "releases" its "lock" on the balls/ball receiver allowing the ball receiver to move to the next gear. We'll wait for your results.
Ed
Ed
Keep the rubber side down!
Re: Shifter adjustment
My approach is to replace the worn parts (ball receiver, springs, washers and wireclip) with stock and eval how it works. In a few months when I split the case to do the bottom end I'll give the Space Age Springs a try. At any rate, springs and other shift parts are wear items and need periodic replacement.
Keepin' the Shiny Side up
on a '72 Wombat 94
--Bill
on a '72 Wombat 94
--Bill
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