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Looking at DRC's dyno video, the big thing I noticed was that he was using a different shift pattern, down on the lever to shift up a gear.

I read up on the advantages and disadvantages of this, the biggest for a street bike being that, if the rider also has a track bike that uses it, or plans on getting a track bike that uses it, the muscle memory is retained. And the biggest advantage for a track bike is that it does not upset the chassis as much when coming out of a corner and upshifting as a standard 5-up pattern can (easier to push down smoothly than it is to pull up smoothly).

I know it is possible to convert as our shifter uses a linkage outside the gearbox, so all that would be required would be to reverse the direction of the linkage attachment point on the shift lever so that a press downward moves the gear selector the opposite direction.

My question is, is this possible with the stock unit, or would new rear-sets be required to do this?
 

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So, after pulling the stock piece and playing with it for a bit, I've decided that you could pull the shift lever modify it so that i could be mounted reverse from how it is now so that the shift linkage connects over the top of it, rather than hang underneath it. I don't know if I worded it very well... but basically you would need about a 1/3inch-1/2inch shim, a longer bolt, and to move the little grip part to the other side of the lever.

Still not sure if I'm explaining it very well, but hopefully you get what I'm trying to say.
 

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i think youve explained it well enough for somone to figure out. i like the idea of shifting down instead of up.
The thing is i believe its setup this way to make it safer. if you suddenly need some extra power to get out of a situation its easier to push down on the lever. if you need less power its easy to just pull the clutch.
so with the stock setup you have both extra power or less power at the flick of a joint, but u have to think about moving up a gear a little extra.
 

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A bump from out of the past!

I am looking to convert my CBR250R to a GP shift pattern. Has anybody done this? I converted my Aprilia Futura. The external shift linkage is similar to the Honda, but no extra parts were required. I merely had to invert the lever on the gearbox so that the linkage moved in an "X" pattern as opposed to a parallelogram. It looks like there would be an interference if I did the same on the CBR250R. Does someone offer aftermarket parts so I don't have to bugger up the OEM linkage?

I have been riding for rears with the GP shift pattern. It is very positive and natural. My Nortons came from the factory with a 1 up and 3 down pattern.
 

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A bump from out of the past!

I am looking to convert my CBR250R to a GP shift pattern. Has anybody done this? I converted my Aprilia Futura. The external shift linkage is similar to the Honda, but no extra parts were required. I merely had to invert the lever on the gearbox so that the linkage moved in an "X" pattern as opposed to a parallelogram. It looks like there would be an interference if I did the same on the CBR250R. Does someone offer aftermarket parts so I don't have to bugger up the OEM linkage?

I have been riding for rears with the GP shift pattern. It is very positive and natural. My Nortons came from the factory with a 1 up and 3 down pattern.
This is one such reverse shift set up that I happen to see recently: BABYFACE : ReverseKit [002-H017]

I can't say that I know anything about it though.
 

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I started riding Nortons back when Old Shep was a pup. They came from the factory with a 1 UP and 3 DOWN GP shift pattern. The hard thing getting used to was when the USA mandated that all motorcycles would shift on the left hand side. I convert all my motorcycles to the GP pattern to eliminate confusion.
 

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I don't think I could get the hang of it, at least not without having to consciously think about it. Too many years of being use to 'one down, five up' (or four up in the case of the XR's).
 

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I don't think I could get the hang of it, at least not without having to consciously think about it. Too many years of being use to 'one down, five up' (or four up in the case of the XR's).
+1. Always 1 down 5 up for me, would confuse me for quite awhile. Be riding along, go to change up a gear, click it up, instead drop down a gear and wheel lockup. :p
 

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I am racing a cbr150 next weekend with race shift,
at least ive got all Saturday tuning day to practice/ swap it back/crash trying.
 

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If you go for 5th gear, does it go back to 1st gear again?
No, the Nortons had a positive stop. But the Hodakas (Pabatco) did not. You could go from fourth to first in a hurry! They did have some of the greatest model names ever:

Dirt Squirt
Combat Wombat
Road Toad
Super Rat
 

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Looking at DRC's dyno video, the big thing I noticed was that he was using a different shift pattern, down on the lever to shift up a gear.

I read up on the advantages and disadvantages of this, the biggest for a street bike being that, if the rider also has a track bike that uses it, or plans on getting a track bike that uses it, the muscle memory is retained. And the biggest advantage for a track bike is that it does not upset the chassis as much when coming out of a corner and upshifting as a standard 5-up pattern can (easier to push down smoothly than it is to pull up smoothly).

I know it is possible to convert as our shifter uses a linkage outside the gearbox, so all that would be required would be to reverse the direction of the linkage attachment point on the shift lever so that a press downward moves the gear selector the opposite direction.

My question is, is this possible with the stock unit, or would new rear-sets be required to do this?
the main reason is that when your bank over in a left long turn you can change gear at a fully over angle if your lent over fully u cant get your boot under to change gear
 

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the main reason is that when your bank over in a left long turn you can change gear at a fully over angle if your lent over fully u cant get your boot under to change gear
Wrong... changing gears while leaned over in mid corner is one of the two worst things you can do... the other would be using the front brake while leaned over in a corner. Proper cornering technique involves doing all your downshifting before turn in, so that you are entering a given corner in the correct gear that allows you to accelerate out of the corner long enough for the bike to return to nearly vertical before upshifting.

The advantage of a GP reverse shift linkage is that the rider has a minimal amount of foot movement when executing upshifts, which means quicker upshifts... which translates to quicker lap times.
 

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Racing and street riding ends up a little different with technique here. ^
I'm not sure what you mean?... I don't think it really matters whether you're on the street or on a track, changing gears while leaned over into a corner is just asking for trouble.
 

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...snip....

The advantage of a GP reverse shift linkage is that the rider has a minimal amount of foot movement when executing upshifts, which means quicker upshifts... which translates to quicker lap times.
Not only that, but think about this. With a conventional shift pattern, have you ever blown a downshift? Have you ever missed a quick upshift? I bet the answers are NO and YES, in that order. Stomping down on the shift lever is very quick and positive. I can do it without my foot on the peg, just raising my foot off the ground after a stop. Upshifting with a conventional pattern, first you have to position your foot, then place your boot under the lever, then lift up. Plus, when you do downshift, normally the bike is vertical as you are braking.
 

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I'm not sure what you mean?... I don't think it really matters whether you're on the street or on a track, changing gears while leaned over into a corner is just asking for trouble.
Without a thorough explanation, there are times on a race track when you will need to shift when leaned over, roll off the throttle when leaned over, and use the brakes when leaned over in a corner.

You always have 100% traction, either vertical or leaned over, but when more traction is needed for cornering less traction is available for either acceleration or braking. If you break 100% you crash.

Both Keith Code and Simon Crafar teach this, but have different ways of projecting the idea IMO.

Using GP shift and a quick shifter the shifts are almost seamless.
 
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