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View Full Version : Single track vs dual track idler wheels


James Park
18-05-2002, 03:45 PM
Dual track (I first saw one on a High Country bow some years ago, Hoyt now has them).
Advantages: Easier to make the strings because each half of the string is shorter, and hence fits on a normal string jig a bit more easily. You can twist one of the parts to alter the draw length (and hence not disrupt your peep position if you twist the inside half).
Disadvantages: More mass, and hence takes more energy to accelerate when you shoot the arrow, therefore slower (simple physics). Also a problem because the additional mass is on the outside of the wheel, where it hurts most.

Single track (most other bows, and High Country has gone back to them).
Advantages: Lighter, and hence faster.
Disadvantages: You need a monster of a string jig because of their length (but then I buy mine ready made, so no problem).

They are equal for: String stretch. It is the combined stretch of the string or the two parts of the string that matters, not the stretch of one half of the string in the dual track type. For either dual or single track the total length of the string is about the same (in fact on the High Country the two halfs were in total longer than the equivalent single string). Hence, the total stretch will be about identical. Hence, neither has an advantage in relation to string stretch.

Hence: in summary, I do not see any real advantage in the dual track idler wheels (no great disadvantage either, except a tiny bit slower). I do expect, however, that the fact that it is different will mean it will be used for a marketing advantage (and most archers will have forgotten about the High Country dual track wheel by now anyway).

James Park
18-05-2002, 11:12 PM
I should add one further advantage of dual track idler wheels: probably less peep rotation.
Hence: probably a tie.

Marcus
18-05-2002, 11:53 PM
What about better string angles?
The single track idlers have odd string angles as the top wheel is in the centre and the bottom cam is offset. The dual track does away with that diagonal string issue.

Also a dual track doesn't have any free idler wheel movement at shot time, the singles do. If you mark the idler wheel you will see that it free spins on shots (even a small amount)

Also Hoyt's engineers have found the string offset on the single track causes inconsistant wear on the inside of the wheel over time causing groups to get larger. This is only a small amount, but still a factor.

James Park
19-05-2002, 07:10 AM
I agree that with the duakl track wheel the string is a little bit straighter down the bow, but I don't think it matters. You need to align you sight bar with the string in either case, and both will be equally accurate.
Similarly I don't think it matters at all that the idler wheel moves it position from shot to shot (and I agree that they do). They are made on a lathe and are nicely round, so even if they move the bow will shoot identically, so of no consequence.
I have not noticed wear on the inside of the wheel, and I have shot them for a long time (maybe it is the better quality of the PSE wheels!!).
So, I still think they are about equal in performance.

Marcus
19-05-2002, 12:13 PM
HAHA yeah I'm sure it's a quality thing. :)

From what I can gather there is wear starting to show after about 1000 shots. That wouldn't be enough for shooters to notice, but something that I'm sure they are trying to eliminate. Afterall the only way to build a bow that is forgiving enough to shoot 1440 is to remove all doubt in wear and varience.
Not that I will shoot a 1440 anytime soon. Neither will most people buying a new bow.

I'm very interested to see how the Dual Tracks go in FITA competition.