you're such a smart guy roger

 

he is....

 

thats why

 

im old i know stuff

 

I'm not old... But I know stuff... Usually from finding out the hard way... Like don't play with fuses with your key on, you might blow your ecm... Well one of the things I found out, is that even with doing the work yourself, you can usually find a motor cheaper than you can fix a busted tranny...
I bent a shift fork and was determined to fix it. My buddy offered me a motor of, well we'll call it elevated temperature, which would have numbers to match my frame... But i'm stubborn so I declined... ******* thing cost me 430 bucks in parts... 3 gears, 1 shift fork, oil, hondabond and 2 seals...

Long story short, gears run 50-120 bucks a piece... Now if your doing just 6th that around 120 bucks... Someone mentioned just replacing 5th with 6th, but the problem is that the two gears are on opposite sides and the dogs face opposite directions, so that won't work...

So roughly to do 5th and 6th its 240-300 bucks for gears alone... The works not to difficult, it just takes the service manual, so mechanical knowhow, and time... I've got it down to about 6 hours to pull the motor and open the lower end, and reinstall... More depending on the job...

Some were getting excited about running from the cops... But its not going to happen... Realistically, your only going to get 20 mph out of it without hitting huge dead spots... So either way your not gettin away, but you could run 70 down the freeway without your arms rattling off...
Now the question is, is 200-300 bucks plus 6-10 hours of wrench time worth it?

Just go buy a transportation bike

 

I'll chime my two cents in real quick.

I've wanted to build up a decidated stunt tranny for a couple years now. Nothing to do with top end speed vs rpms, but to drive the torque curve lower.

The problem I couldn't grasp fully was how to change the gearing on the imput shaft. Changing fifth or sixth is all fine and dandy on the output side, but what do you do to the ratios of the imput shaft that drives those gears?

I can't see any way to replace a single gear with a different diameter. It would require changing the respective gearing on the imput shaft also. But I could be mistaken.

***edit***
If I remember correctly, fifth gear also contains neutral on the kawi's so keep that in mind also.


On a side note, didn't yamaha run a seven speed tranny at Daytona in the early 90's? I remember hearing about it, but the details are fuzzy. Nobody could catch the yamaha on the banking, and during teardown it was discovered there was a seventh gear. Rumor had it that it must have been a +200K transmission!

 

i hear that...

 

I think Neutral on every bike is done different, everything i know is on the GSXR... but one thing doesn't change no matter the set up... for a longer gear, the gear on the driveshaft (attatched to the clutch) has to go smaller, and the corresponding gear on the countershaft (attatched to the sprocket) has to go larger...

The reason you can't go any shorter on 1st, is because the gear on the countershaft is already really small, driving a large gear and it can't go much smaller for the same reason you can only go so small on your front sprocket... and on GSXRs to change that gear, means replacing the entire shaft

 

just a thought not really serious about this but it might be fun to make one any way , how about a dolly kind of thing that turns yous bike into a sort of three wheeler ...your back tire would turn a roller that turns the two rear wheels so you could have any gear ratio you wanted and the bike would just strap into it so when you got to the spot you just unstrap the bike and ride it off the back two wheels ...

i know it's sounds gooffy as hell but it would be kinda cool ,you could even get real fancy and make it like a real trike rear end with storage compartment for tools gas and drinks...lol

 

picture some thing like this but the bike just rides out of the middle of it




http://www.ratraceproductions.com/three-wheeler.jpg

 

that would be pretty sick

 

I guess that was the point I was trying to make, except I was using imput vs output shafts, instead of countershaft vs driveshaft. If you change the gearing on one shaft, you also have to change the gearing on the corresponding shaft. Can't do one without the other.

Neutral gears I've only seen on third or fifth gear, but can't remember which bikes at the moment and too lazy to look it up.


Very interested in the concept and will be checking this thread often.

 

for my GSXR is not really on any gear, all the gears that move are put into the middle position so they never contact any other gears...

But all it would take would be to find someone to make the different sized gears, or figure out which other bikes gearing you could use... mosty its just a lot of homework...

 

+1 maybe a vid going throught the gears and what 6th gear is like on the highway.Id be willing to purchase for big rides

 

it's a good idea, i would want a long 6th, and i need a 7th gear for my street 06 636

 

I hadn't thought about that.

What about swapping the entire tranny with one from the same make and model liter bike? Driveshaft, countershaft, drum and forks.

In theory the lower cases will be dimensionally close, so it might be possible.

Once again, I'm just guessing. I have never compared the size differences.