J trans help ?

i am obviously new to the Kaw world. i am building a set of 1980 MKll cases & crank [welded] and useing a J head, big block turbo kit.
Thing is I have heard from realiable sources that the trans is good to use but it has a 2nd [or 3rd] gear ratio difference between the J mdl. And I can put the money into getting the J trans. back cut and a few hardened shift shafts and forks and financialy as well as reliability be about the same money. Forget the GPZ trans. thats just way too much money to have converted although stronger. Thing that is confusing me is it seems the J is differnet from the GPZ, KZ, and MKll. Can anyone tell me with certainity what year/s and mdls. I can find a J trans.? Been on e-bay and they list them as J/GPZ but when I send seller a QUESTION as far as 'is this a J mdl trans.' ? 3 replies have been NO? Why are the listing them as J/GPZ then?
I can go back to where I get some of my information but to be honest these guys are getting tired of me I think.lol Lots of questions when doing a project of this caliber. Turbo, head, cases, all that stuff I have learned from them. So I would like to find this out on my own. And if anyone knows of anybody selling one. Forward my info to the seller I would appreciate it emencly!.....edspring1@yahoo.com
Thanks all!

check APE.com they are listed in the links sectionB)i hecked apes site.they list the 1000j/gpz1100 as same trans.they show a listing for a conversion bearingset to install the newer trans in the older cases without needing special shafts. my engine buide didnt think i would ave any trans problems using the z1 trans in my project but we are using a heavy duty 2nd gear and undercutting the rest of them.what is your turbo project consisting of?

Post edited by: wireman, at: 2007/01/21 18:49

if hes the same guy on dragbike.com, its going to be a 1200cc turbo
Scott

cool,im waiting for ape jay to jump in and explain the differance in the 2 transmissions.

link to DB.com thread about tranny swaps
some info from that post so its in the KZR database for future searchs:

The following should be done with a complete undercut job and be performed by an experienced technician for best results.

To fit the J/GPZ trans in the Z1/KZ case the mods are as follows: Input shaft: Using a J input shaft you must bore the threaded end so the 3/8” ball and the Z1 pusher fits inside. Using a GPZ shaft the threaded end must be shortened and re threaded as well as boring.

The 5th gear input needs to be turned down to clear the shift drum and the drum must also be turned because you cannot take all the material from just one of them.

The 4th – 5th fork must be clearanced on both sides to clear 3rd and 4th gear on the input shaft.

A conversion bearing, spacer and seal are also necessary.

There is also some re shimming to be done on both shafts to obtain proper neutral clearances and engagements. If this is not done correctly, it will get itself into 2nd and 5th at the same time and cause considerable damage. I’ve seen it plenty of times. Chewed up teeth and broken dogs—Very ugly!

There are two different 3rd gear sets and output shafts. The J has 21/30 T and the GPZ has 19/ 27T. They are both the same ratio, but the GPZ set uses a larger tooth pitch with less teeth. The J output shaft uses a bolt to secure the sprocket and the GPZ uses a nut and also has about 3mm. more spline. The GPZ parts are the more desirable ones. If you cannot find these parts, the gpz output shaft (13128-1048) and 3rd input (13129-1566) are still available from Kawasaki. The 3rd output is no longer available, but I make a replacement that is stronger than the stock one.

There are a few more small details, but this is the majority of what has to be done.

Scott

Post edited by: 77KZ650, at: 2007/01/21 23:55

show off! check out the adaptor bearing kit APE sells,maybe jay can explain it to us;)

I just found the info and quoted it, I dont take credit for actually knowing it:laugh: :silly:
Yeah, Jay should be able to give us the rest of the details...I hope he chimes in on my dry nitrous thread for my ZX12R on the dragbike.com forums too...hint hint:P A couple guys are saying Muzzy has a better kit that APE :ohmy: ????

dont worrie jay will have them taken out with a smart bomb shortly!:evil: nobody can build the best tool or best part for every situation i learned that the hard way over the years:case makes killer skidloaders but their backhoes suck,john deere makes killer backhoes but their skidloaders suck! look at shnitz(?)racings site every other part they sell has APE stamped on it:whistle:

I know APE has great quality stuff, but the systems are different. APE's dry kit puts the nitrous into the airbox, while Muzzy's dry kit has individual nozzles that spray directly over the throttle bodies. the "Muzzy guys" are saying it takes less gas to make the same horsepower with the 4 nozzles. Im waiting for a response from the "APE guys" to that one. And from reading from another site, when the airbox is pressurized with the giggle juice (like APE's kit) the "power" comes on in a more gradual and controllable rate instead of an instant "snap" of power (think wheelie on the push of a button when you want to go fast, not up).......
there, completely off topic :whistle: srry

back to KZ trannys....