EXUP Worldwide was born from the ashes of the original EXUP Brotherhood – the definitive forum for all those who have interest in Yamaha FZ, FZR, and YZF motorcycles.
Hi, this is my first time posting. Just wondering if anyone has info on back
cutting gears. I have talked to one local bike shop and they recommended
back cutting gears/dogs as a way to improve gear engagement. I have torn down motor and swapped in good used trans. just waiting on gasket set to arrive. If I'm in this deep I figured I might as well have this done. I would appreciate any info. Thanks
YES!!! If you are in that deep, have someone that knows what they are doing, and you can afford it, then do it. If any of the about are false, then don't. I was in that deep, had some resources, but low on $ so I didn't.
I did install a YZF750 6-speed and had a BRAND NEW 2nd gear set installed in my FZR1000.
There are some who call me........Tim?
In Memory Of John "Silver" Douglas (Dec. 08, 2008) R.I.P. My Friend.
I was also wanting to know what exactly is done when back cutting. Do they machine the ends of the dogs? and if so does this change how far the shift forks would have to travel in order to engage? I'm not sure if I'm correct but wouldn't maching the ends of the dogs remove the tempered quality of the metal?
I cut gears, then re heat treat. But the best , and I mean the BEST guy on the planet top talk to is Bill Robinson.
Do a google for him and gearbox's you'll get a hit.
Jim
Hey Kid...
Is my tail light still working?
"...you can't tune a motor that's hurt. They run much faster on fuel then they do on aluminum." - Elmer Trett
I have read an article of someone who advised NOT to cut back the dogs/holes of a FZR gearbox.
The angular contact of the dogs/holes creates an axial force on the sliding gears who will press against the shift forks, and they are the one to fail on a short notice. Back cutting is nice for dragracers and/or other bike with a limited lifespan, but not for the street if you don't want to strip your engine within a year to replace totally worn shift forks.
Don't know if this is true, but I do have noticed the fact that there is no end-stop for the sliding gears in a FZR tranny, they are kept in position only by the forks so this story could be true.
Thanks for the info everyone, I think I'm going to hold off on doing this for now. I've only had the bike for 6 months and it was on the road for about 400 miles. I'm using good pieces so I think/hope they will hold out for a while, if not I'll just split the cases again. Piece of cake!!!
James and 
