Topic: left hand or right foot shifting, road racing

[gschuld]

I'd like to get some opinions regarding shifting mechanisms for cb750 road racers.

I have found several options.

1- I believe all 970 kit cr750s had right foot shifting.  1st picture.   Obviously it worked, but what I don't really get is why?

2- Left foot shifting with the "standard arrangement"  single shift linkage from oem shifter position to rearset location. 5th picture

3- Left foot shifting with a two linkage system.  First linkage rod goes up from the OEM shifter loation, then a bellcrank allows the second linkage to run down and back toward the rearset location.  I'm presuming the reason for this is to have the second linkage offset inboard so keep the pedal location farther inboard.  2nd picture.

4- Left foot shifting with the shifter facing back from the oem location allowing the rider to effectively shift the bike in reverse motion.  Like on the 1975 Yoshimura built endurance racer.  It allows for the simplest system, with no extra linkages, but the reverse action would feel a little odd.  3rd and 4th picture.

George

[bwaller]

Don't forget this was different from the British invasion.  Everything shifted on the right and obviously most of the riders were accustomed to right hand shift.

The left lever facing rearward is called GP shifting, opposite to what most are used to on the left side. So some maintain the stock shift pattern (1 down, 4 or 5 up)with linkage or turn the pedal backwards for GP style (up for 1st). It can be confusing to the rider to ride different bikes GP vs stock pattern. At least for me.  My race bike is stock, our endurance bike is GP...I guess I'll change mine to GP. Then I can make all my mistakes on my street bike!!

[gschuld]

Right foot and GP shifting sounds like a recipe for disaster for me personally.  I have way too much time with standard direction left foot shifting sohc Hondas to change now.  I kind of like the double linkage left hand shifting system, leaving the two linkages straight and allowing the rear pegs to be tucked in more without fouling the linkage.   It's relatively complicated, like the CR 970 kit stuff is(but without crossing through the frame left to right) but done well with a ball bearing guided offset bellcrank and using linkages with good ends, it could work well and allow for easier adjustability in moving the peg location around a little bit if needed.

George

[turboguzzi]

i raced with road setup for the last seven years for the same reason, not that much in it, maybe when i'll be searching for those last few tenths to do lap records.... not there yet.  since have moved on since 1970, that mech in the pic looks complicated...  keep it simple...

[dusterdude]

Right foot shifting was standard on the sportster and some,maybe most brit bikes until roughly 1975.those bikes were that way because they ran flattrack here in the u.s.they were changed in 75 due to the influx of jap bikes which are left foot shift,so the u.s. govt dictated the change

[Retro Rocket]

Right foot and GP shifting sounds like a recipe for disaster for me personally.  I have way too much time with standard direction left foot shifting sohc Hondas to change now.  I kind of like the double linkage left hand shifting system, leaving the two linkages straight and allowing the rear pegs to be tucked in more without fouling the linkage.   It's relatively complicated, like the CR 970 kit stuff is(but without crossing through the frame left to right) but done well with a ball bearing guided offset bellcrank and using linkages with good ends, it could work well and allow for easier adjustability in moving the peg location around a little bit if needed.

George

GP shifting is extremely common George, what it does is stop your foot being jammed under the gear lever for up shifts coming out of corners while still lent over, by keeping your foot above the gear lever... Takes a little getting used to but lots of people use it...

[CBGhia]

Right foot and GP shifting sounds like a recipe for disaster for me personally.  I have way too much time with standard direction left foot shifting sohc Hondas to change now.  I kind of like the double linkage left hand shifting system, leaving the two linkages straight and allowing the rear pegs to be tucked in more without fouling the linkage.   It's relatively complicated, like the CR 970 kit stuff is(but without crossing through the frame left to right) but done well with a ball bearing guided offset bellcrank and using linkages with good ends, it could work well and allow for easier adjustability in moving the peg location around a little bit if needed.

George

GP shifting is extremely common George, what it does is stop your foot being jammed under the gear lever for up shifts coming out of corners while still lent over, by keeping your foot above the gear lever... Takes a little getting used to but lots of people use it...

I switched my Ducati to GP shifting and rode that way on the street for a few years.  You get used to it very quickly and can usually go back and forth pretty easily.  I thought about switching my Honda to GP shifting, as well.  Maybe one of these days.