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69Cobra · 10-04-2014, 12:30 PM

Just trying to think this through... If I'm thinking right the fingers go through two different acts during the 3/4 shift. The first being the disengagement of 3rd gear. What I don't understand is what does it matter on the disengagement of 3rd gear if we are running the extra long shift arms and/or extra tall shifter in this phase? If the finger needs or takes say 10 ft/lbs of force/torque to disengage from the 3rd gear dog ring then it take 10 ft/lbs no matter if we are using extra long or extra short shift arms or shifters, right? In this phase of it the extra long or short just effects how much effort we have to use in order for the shift finger to see the 10 ft/lbs of force to disengage 3rd gear.

Now phase two engaging 4th gear...
If there are not stops being used or not set correctly the shifter can put extra strain on these fingers (and everything else) by bottoming out the slider to the dog ring. In this scenario the whole system from the shifter to the dog ring will see whatever force is applied from the end user. If you pull the extra long or short shifter with 100 ft/lbs of force the shifter arm, finger, fork, slider and dog ring all see 100 ft/lbs of force. To me, if one has stops and the stops are set to where the internals of the transmission do not see any bottoming out situations then all of the 100 ft/lbs of force applied to the shifter by the end user stops at the shifter stops.

In this whole scenario here the only thing that is not taken into account is any force that the slider sees when it meets the dog ring before they mesh together. So before the slider and dog ring actually go into full engagement they do collide and to me its at this point that the stress of the whole shifting mechanism sees the most force and there is nothing you can really do about it. Now the extra long shifter and arms obviously lets you apply more force in this part of the process but you are actually moving the shift fork slower because the extra long stuff has you that much farther away from the pivot point than if you had the shorter arms and shifter. So now you have a comparison between speed and force.

Thoughts???

10-04-2014, 12:30 PM	#69
69Cobra Senior Member Join Date: Aug 2007 Location: California, Ky Posts: 669 Likes: 61 Liked 2 Times in 2 Posts	Re: Anyone have a shift finger for Jerico? Just trying to think this through... If I'm thinking right the fingers go through two different acts during the 3/4 shift. The first being the disengagement of 3rd gear. What I don't understand is what does it matter on the disengagement of 3rd gear if we are running the extra long shift arms and/or extra tall shifter in this phase? If the finger needs or takes say 10 ft/lbs of force/torque to disengage from the 3rd gear dog ring then it take 10 ft/lbs no matter if we are using extra long or extra short shift arms or shifters, right? In this phase of it the extra long or short just effects how much effort we have to use in order for the shift finger to see the 10 ft/lbs of force to disengage 3rd gear. Now phase two engaging 4th gear... If there are not stops being used or not set correctly the shifter can put extra strain on these fingers (and everything else) by bottoming out the slider to the dog ring. In this scenario the whole system from the shifter to the dog ring will see whatever force is applied from the end user. If you pull the extra long or short shifter with 100 ft/lbs of force the shifter arm, finger, fork, slider and dog ring all see 100 ft/lbs of force. To me, if one has stops and the stops are set to where the internals of the transmission do not see any bottoming out situations then all of the 100 ft/lbs of force applied to the shifter by the end user stops at the shifter stops. In this whole scenario here the only thing that is not taken into account is any force that the slider sees when it meets the dog ring before they mesh together. So before the slider and dog ring actually go into full engagement they do collide and to me its at this point that the stress of the whole shifting mechanism sees the most force and there is nothing you can really do about it. Now the extra long shifter and arms obviously lets you apply more force in this part of the process but you are actually moving the shift fork slower because the extra long stuff has you that much farther away from the pivot point than if you had the shorter arms and shifter. So now you have a comparison between speed and force. Thoughts??? __________________ Kris Rachford 69 Cobra 428CJ 4 Speed C/S 3032 Last edited by 69Cobra; 10-04-2014 at 12:33 PM.