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Discussion Starter #1
One of the things I'm interested in trying out with CBR300 is a GP shift conversion, its a relatively easy mod to do and one that I think many people are curious about...

We all know traditional shift patterns, one down for first, 5 up for second to sixth. There's really no problem with traditional shifting, however if you're a track rider or looking for something a little more intuitive GP shift could be for you. By intuitive I mean its a much more natural reaction at high speed to push down instead of click up. Ever drive a BMW with an Auto-Manual? They are the only gearbox in the industry that down is upshift, its just more intutive to go down, with the momentum. Although that may be subjective (isn't it all ;))



The issue Traditional shifting runs into is cornering. On track, or even your favourite bendy bit of tarmac, while leaning a right hander, its far easier to click down for upshift as you roll the throttle on than manoeuvring your feet about while hanging off the inside!



even worse are the left handers, trying to hook your toes under the lever while leaning left means you run the risk of toe scrape. Again, far easier to click down.



I suppose the hardest part of switching to GP shift is going to be the learning curve. I've read many a stories about missed shifts actually more like accidental downshifts because said pilot forgot he switched his pegs. Also it seems like downshifting is going to need a new dash of finesse, Its much easier to mash down a couple than flick up a few.

Most bikes the swap is easy enough you can just flipping the sleeve on the end of the shift spindle. Some bikes will need new rearsets however. I'm not sure if its better or even worth, but it seems like a simple mod that I'd like to at least try out :D
 

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This is one of those things that is all a matter of preference. I say you should go for it, and see if you like it. You basically laid out the pros and cons. Easier to shift up, but harder to shift down. I'm sure you will learn pretty quickly if it is for you or not. Are you sure the mod is easy to do? I just imagine it would suck if you took all this time to switch to GP shift and then you didn't like it and had to spend a whole bunch of time switching back again.
 

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motomike is your cbr GP shift?
No, definitely not... I'm too accustom to the conventional one down - five up shift pattern to want to try and re-train myself for just one of my bikes (my XR's are all conventional pattern as well).

The main advantage, and reason for the use of the GP shift pattern is that upshifts are a split second quicker for track & race bikes that are equipped with it. I can't see any real reason for using it on a street bike.

By the way, a GP shift pattern is actually not intended to make shifting possible when the bike is leaned over at a radical angle in the apex of a corner. When a race bike is leaned way over in a corner like that, the rider is already in the correct gear that he needs to be in for that corner... after clipping the apex of the corner, and by the time the rider is ready to make his next upshift, the bike is well on its way towards becoming upright as it exits the corner. The same applies to making downshifts when entering a corner... downshifts will be done well before the bike is completely leaned over at the apex of the corner. For those few moments that a road racing bike is fully leaned over in a corner, it's all about throttle control... if you found yourself needing to change gears while leaned way over in mid corner because you were in the wrong gear for the turn, you could potentially lose your track position to another rider, or even worse, upset the bike's chassis and find yourself flying off into the grass or gravel trap on the outside of the corner.
 
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well regardless of extreme leans or not

you should always downshift before you turn anyways.

i've toyed with the idea of switching to GP to try it out
 

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well regardless of extreme leans or not

you should always downshift before you turn anyways.

i've toyed with the idea of switching to GP to try it out
Exactly... even for normal everyday street riding, mid corner gear shifts are a bad practice.
 

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Discussion Starter #10
I think GP is more intuitive. When your moving its more natural to stomp down more more, and when slowing up, pulling up on the lever. Much like BMW analogy in the OP. The motion just flows with the motion...
 

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I think GP is more intuitive. When your moving its more natural to stomp down more more, and when slowing up, pulling up on the lever. Much like BMW analogy in the OP. The motion just flows with the motion...
It would not be at all intuitive for anyone who has spend the better part of a lifetime riding bikes with a 1 down, 5 up (or in the case of large displacement off road thumpers, 4 up) shifter... it would be a bit like teaching old dogs new tricks.

On the other hand, for someone who is just starting out as a new rider, the GP shift pattern should be relatively easy to pick up as habit, as you'd have no muscle/mind memory to overcome from being accustom to a conventional pattern. However, someone who becomes use to the GP shift pattern (where it becomes second nature) likely would have the same "old dog, new trick's" issue when jumping onto a bike with a conventional pattern.

As for the analogy with the BMW car transmission, it's really not even similar to a motorcycle foot shifter. With that BMW shifter, you are pulling back for the up shift, and pushing forward for the down shift. But that BMW shifter is unique in its own right... it's not like nearly every other car has a standard, or 'conventional' shifter that is the opposite, as in you would push forward for up shifts, and then pull back for down shifts.

With a GP shift pattern, your foot is still going through the very same motions as it does with a conventional shift pattern... that aspect of shifting a motorcycle gear box doesn't change.

It's kind of funny how many new motorcycle riders will equate shifting a bike to that of shifting a manual transmission car, when there really is very little in common between the two, aside from the need for hand & foot coordination. Operating a clutch pedal with the left foot, and a shift lever with the right hand on a manual gearbox car, does not transfer in any meaningful way to operating a motorcycle clutch lever with the left hand and a shift pedal with the left toe.
 

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id say knowing how to drive a manual car does help a bit with learning how to ride. and vice versa

you get the basic understanding of what the clutch is for and how it reacts with the RPM and traveling speed.

ud be surprised how many people i try to teach who dont get it. especially girls..

the concept is similar.. you are just using different body parts to control different aspects
 

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Discussion Starter #15
It would not be at all intuitive for anyone who has spend the better part of a lifetime riding bikes with a 1 down, 5 up (or in the case of large displacement off road thumpers, 4 up) shifter... it would be a bit like teaching old dogs new tricks.

On the other hand, for someone who is just starting out as a new rider, the GP shift pattern should be relatively easy to pick up as habit, as you'd have no muscle/mind memory to overcome from being accustom to a conventional pattern. However, someone who becomes use to the GP shift pattern (where it becomes second nature) likely would have the same "old dog, new trick's" issue when jumping onto a bike with a conventional pattern.

As for the analogy with the BMW car transmission, it's really not even similar to a motorcycle foot shifter. With that BMW shifter, you are pulling back for the up shift, and pushing forward for the down shift. But that BMW shifter is unique in its own right... it's not like nearly every other car has a standard, or 'conventional' shifter that is the opposite, as in you would push forward for up shifts, and then pull back for down shifts.

With a GP shift pattern, your foot is still going through the very same motions as it does with a conventional shift pattern... that aspect of shifting a motorcycle gear box doesn't change.

It's kind of funny how many new motorcycle riders will equate shifting a bike to that of shifting a manual transmission car, when there really is very little in common between the two, aside from the need for hand & foot coordination. Operating a clutch pedal with the left foot, and a shift lever with the right hand on a manual gearbox car, does not transfer in any meaningful way to operating a motorcycle clutch lever with the left hand and a shift pedal with the left toe.
Lets use our free association skills a little bit eh, Every manumatic, tiptronic whatever you want to call it gearbox in cars is push forward for up, pull down for down. In that sense yes the BMW is analogous to GP shifting.





No one was saying the BMW and motorcycle shifting WERE THE SAME. I'm saying the intuitive motion of motion is the same. Flowing with the momentum if you will. Pull down for upshift flows with the motion of acceleration, Downshifting has the same motion to motion flow, push forward for downs, kick up for downs (especially as you're typically coming out of tuck at the same time)

And again no I'm not equating a manual car to a motorbike, but the motion of motion! I've ridden dirt since I was a teen, but I like new tricks ;)
 

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A quick revisit:
So has anyone done this yet? Being a new rider without any movements that have become habitual, I think this sounds like a great thing. I have actually stomped on the clutch once or twice when trying to upshift (im new, whatever), but thankfully my reflexes are trained and I was able to pull the clutch in quickly to avoid an uncontrolled boost.
anyway, curious to know if anyone has done this yet and how long it too to modify.
 

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A quick revisit:
So has anyone done this yet? Being a new rider without any movements that have become habitual, I think this sounds like a great thing. I have actually stomped on the shift pedal once or twice when trying to upshift (im new, whatever), but thankfully my reflexes are trained and I was able to pull the clutch in quickly to avoid an uncontrolled boost.
anyway, curious to know if anyone has done this yet and how long it too to modify.
I think you meant to say shift pedal.;)

Have you read through some of the previous posts here? There are a number of good reasons as to why virtually all motorcycles are built with the conventional 1 down, 5 up shift pattern, and which have been discussed in some of these previous posts in this thread.

The GP shift pattern really only has an advantage on a race track, where gaining a couple thousands of a second in a single lap can make a huge difference over the course of a race distance. A GP shift pattern on the street will do nothing for you in terms of making you a better, more proficient rider.
 

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I think you meant to say shift pedal.;)

Have you read through some of the previous posts here?
yep, meant to say that yes. Shifter.
and yes, read thru all of it actually. Like someone said, it could come down to a matter of preference I guess. Seems like it would be practical still; street or track. Sounds like something id like to feel out though.
 
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