'76 KZ900 (ZRX1200R) Build
- SWest
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 08:33
I'd back cut them.
Steve
Steve
Z1b1000 1975 Z1b
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- NakedFun
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 08:38swest wrote: I'd back cut them.
Steve
So you would spend $750 with APE even if your trans was still in serviceable condition?
Just asking the question as it is always easy to spend some else's money..... Lol
Cory
2008 Kawasaki Concours 14
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
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- SWest
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 08:40
At least 2nd gear. That's the one that goes first. $750? That's a lot of money. Your choice.
Steve
Steve
Z1b1000 1975 Z1b
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- NakedFun
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 08:47
APE charges $367 to do a complete trans undercut on the acceleration side of the dogs. They charge an additional $367 to do the deceleration side of the dogs as well. So yes.....pricey...
Cory
Cory
2008 Kawasaki Concours 14
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
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- SWest
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 08:51
I did my own. It would've been nice to be able to get them to do it. I use to do them on dirt bikes in the day.
Steve
Steve
Z1b1000 1975 Z1b
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- les holt
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 10:11
I'd definitely do the up cut and not think twice about the down, it isn't even a little necessary. Ape/schnitz/fast by gast are all good, fast by gast maybe a little better of the 3 but noting to make bets over. Over shift bushing and billet 2nd not necessary either, sreet bike doesn't get enough traction or put that much stress on 2nd gear. I know little tire bar slick bikes that's been running for years without it.
Les
Les
www.facebook.com/PdmCustomFabrication
76 kz 900 turbo
77 LTD 1000 turbo
2 78 Z1R's
72 H2
kzrider.com/forum/13-bike-related/491552...one-followed-me-home
accelerate.presspublisher.us/issue/issue-6-2012/article/ltd
www.cycleworld.com/2013/09/04/2013-cycle...-concours-bike-show/
76 kz 900 turbo
77 LTD 1000 turbo
2 78 Z1R's
72 H2
kzrider.com/forum/13-bike-related/491552...one-followed-me-home
accelerate.presspublisher.us/issue/issue-6-2012/article/ltd
www.cycleworld.com/2013/09/04/2013-cycle...-concours-bike-show/
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- NakedFun
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 13:47
Thanks Les. I spoke with Joe and got a price on the up and down cutting, so looks like he will be doing that work as well for me.....
Cory
Cory
2008 Kawasaki Concours 14
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
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- SWest
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 13:50
I had to split my cases for 2nd gear popping out last year. You won't regret it.
Steve
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
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- pete greek1
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 14:35
I almost blew my motor when it was stock, when it popped out of 2nd. gear & buried the tach gauge , I had the motor rebuilt with a 1075, had the trans back cut, & also got a Dyna 2000 ignition , that has a rev limiter, like other people have said, you won't regret it, you already have the trans out, GET-R-DONE, 
Pete

Pete
1980 LTD 1000..,1976 LTD 900, have the 1000&900 now. the rest are previous= 1978 KZ 650 B.., 1980 Yamaha XT 500..,1978 Yamaha DT 400.., 1977 Yamaha yz 80..,Honda trail ct 70.., Honda QA 50...5-1/2 hp brigs & straton CAT chopper mini bike...3-1/2 hp mini bike (WHEN GAS WAS ABOUT 45 CENTS A GALLON)!!!!
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- NakedFun
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 18:14
So now begins the tedious process of blue printing to see what is viable and not.
The gear backlash measurement sucks as it is too easy to get movement out of the corresponding gear. So I found a little trick that is showing repeatability. Taking a medium sized zip tie, I worked it into the adjacent gear sets to help lock it from moving. Then it is very easy to only get the backlash. So far finding the measurements are falling into the middle to 3/4's of the range.
We'll see how it goes.......long process ahead.....lol
Cory

The gear backlash measurement sucks as it is too easy to get movement out of the corresponding gear. So I found a little trick that is showing repeatability. Taking a medium sized zip tie, I worked it into the adjacent gear sets to help lock it from moving. Then it is very easy to only get the backlash. So far finding the measurements are falling into the middle to 3/4's of the range.
We'll see how it goes.......long process ahead.....lol
Cory
2008 Kawasaki Concours 14
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
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Re: '76 KZ900 (ZRX1200R) Build
30 Mar 2016 18:25
These trannys are pretty damn tough.
Steve
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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- NakedFun
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Re: '76 KZ900 (ZRX1200R) Build
13 Apr 2016 15:58
So waiting on my head to get back from Cavanugh's, body from the painter, seat from the upholstry shop, I ordered up these....
Have them on the ZRX and love them. Got custom made decals for them as well that match the bike.
That is it for now.
Cory

Have them on the ZRX and love them. Got custom made decals for them as well that match the bike.
That is it for now.
Cory
2008 Kawasaki Concours 14
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
1999 Kawasaki ZRX1100
1976 Kawasaki KZ900
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