Topic: 750 shift lever pressure for gear change.

[dragracer]

I have a technical question for you fellas. Can anyone tell me the approximate pressure, in pounds, required to upshift the gear change lever through each consecutive gear change. ? I'm referring to making that change when pulling in the clutch momentarily to unload the transmission and not full throttle powershifts.

To explain the reasoning behind my question, I'm brainstorming building my own electric shifter utilizing a high strength electric door popper solenoid. They come in different pounds of pull and various travel length's. Obviously, picking a solenoid with the greatest pull specifications is the way to go. The main issue is; how much shift lever effort , in pounds, is  truly required to make a monetarily interrupted upshift?? I've got my hands on a 40 pull electric solenoid and will push ahead once I get some idea of it takes to do an upshift. Lots more involved to build a reliable system but the electric solenoid is the heart of the kit.

Give me some feedback gentleman. I'm just looking for economical alternatives to a conventional air shifter system.

[mystic_1]

I'm not sure I've ever seen anyone measure this but I'm not a racer.

You could get a ballpark by putting your foot on the floor, placing weight on your instep right where it would make contact with the lever, and seeing if you can lift it just by rotating your ankle.  40 lbs seems like way more force than it takes to shift with your toe.

The other thing of course is the length of your shifter lever will affect how much effort it takes to shift.  The air shifters and electric shifters I've seen tend to attach to the shift shaft with a much shorter arm then the manual shift lever, that'll increase the amount of force needed.

mystic_1

[firebane]

Grab a luggage scale and pull the clutch and lift up with the scale. It will record how much you pulled to shift gears.

[cougar]

You might also use a set of fish weight scales, something like this. http://www.basspro.com/Bass-Pro-Shops-Fish-Scale/product/13327/   Just as an example or thought.   ...cougar...

[POPS 911]

Your left toe of your boot will be all the pressure you will need to shift the HAWK under full throttle, will send you a e-mail got milli second kill switch mounted need to wire up and test ..... bought 8 more switches need to make a pattern for a SOHC 750 bike....... KISS

POPS BK647 NHRA

[mystic_1]

Part of the problem with the scale suggestions is that the force needed to shift is different with the motor running or not, and with the bike moving or not, whether the transmission is loaded fore or aft, etc, and a static test won't show that. 

Really it doesn't take much force if we're not talking about powershifting.  When I want a brisk gear change, I'll "pre-load" the shift lever with my toe, and keep applying light pressure upwards, not quite enough to shift, but enough so that when I do blip the clutch (thereby unloading the transmission) I'm already applying enough pressure to cause the shift to occur, because the required force went down.

The force required has gotta be something less than 10 lbs and even thats a pretty high estimate I think.  How much weight can you lift with your big toe?

mystic_1

[dragracer]

Thanks for the input everyone. Since fish scales are cheap, it might be worth at least gathering that bit of information. True it won't mimic a running bike.

The most practical thing I can do is move forward with a test with the actual solenoid. I think I'll use a dumb bottom end first if I can cobble one together. I don't want to take a chance of bending the shift forks in my race bike as a test mule. I think the concept will work with some fabrication of proper mounting brackets etc..  I'm going to see what Pops comes up with on his kill device and maybe incorporate that into the mix especially if it can be manipulated to adjust kill time. Pingel sells a fully electric shifter kit but its $960 bucks. I paid less than $65 with shipping for the solenoid. If it doesn't work, I can always use it to pop open the door of the street rod I plan to build someday. Lol.

[bear]

I have an English Kliktronic unit on the sidecar. It works extremely well.

[POPS 911]

When I find a clutch SOHC 750 bike to make a pattern to hold this SIMPLE switch I think I will sell mine " ON THE GAS ALL THE WAY, NO CLUTCH TOUCH " for $15.00....... Simple add on with Button head bolts, and a polished aluminum plate mount, cut you hot 12v wire to both coils and wire in this simple switch, toe up NO 12V to coils , down shifting pull in the clutch and ride back to the pits = I did this many times with a WALKER shift drum elec. shift but on that style you had a switch that turn it on or off, kill time was adjusted by thickness of washer under the neutral plug on side of case on KZ's. If it works out then I will raise the price to $960 well $900 the AMERICAN way for a better mouse trap.

POPS BK647 NHRA