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6spdls1z28
12-24-2021, 04:10 PM
I’m picking one of these up Sunday to do the powervalve top end on my tri z. Does anyone know if the 5 speed trans ratio is the same as the z? Merry Christmas everyone!
El Camexican
12-24-2021, 05:30 PM
Awesome project, just started back on mine this week.

Looking at the parts fiche they seems to share some gears, but a few part numbers start with 24Y instead of 38W. Beyond that I have no idea, but I do recall guys just swapping the clutch covers off the Z onto the YZ engines and installing them, so I wouldn’t be concerned, especially if 1st and 5th are the same.

I hope you’ll post your progress.
6spdls1z28
12-24-2021, 06:07 PM
Awesome project, just started back on mine this week.

Looking at the parts fiche they seems to share some gears, but a few part numbers start with 24Y instead of 38W. Beyond that I have no idea, but I do recall guys just swapping the clutch covers off the Z onto the YZ engines and installing them, so I wouldn’t be concerned, especially if 1st and 5th are the same.


I hope you’ll post your progress.

I know the crank is bad on the yz so I can’t swap the whole thing. So was hoping maybe 4th and 5th would be taller, oh well. Plus I wanted to keep my headlight. Maybe I’ll fix the yz bottom for later and swap top ends. I will definitely post pics of my progress!
El Camexican
12-24-2021, 06:39 PM
For sure want to keep the Tri-Z crank/electric if it’s a rider.

86 6 speed would be nice if you could find one.
6spdls1z28
12-24-2021, 07:39 PM
For sure want to keep the Tri-Z crank/electric if it’s a rider.

86 6 speed would be nice if you could find one.
It’s a nice rider right now it’s an 86 but previous owner put a 5 speed in it. Sucks I can’t find a 6 speed anywhere that’s why I was wondering if the yz gears were different
6spdls1z28
12-26-2021, 04:02 PM
Got my donor powervalve today the site won’t let me upload pictures though
El Camexican
12-26-2021, 04:53 PM
Got my donor powervalve today the site won’t let me upload pictures though

Send them to someone else’s phone and ask them to send them back to you. Save the returned photos and they should be small enough to download.
6spdls1z28
12-26-2021, 06:22 PM
Send them to someone else’s phone and ask them to send them back to you. Save the returned photos and they should be small enough to download.
I’ll try it
6spdls1z28
12-26-2021, 07:57 PM
Send them to someone else’s phone and ask them to send them back to you. Save the returned photos and they should be small enough to download.

It still didn’t work
6spdls1z28
12-26-2021, 08:34 PM
Alright had to send it to yet another phone and it worked so here’s my donor
6spdls1z28
01-05-2022, 12:27 PM
After cleaning the jug and splitting the yz cases I have a nice spare tranny and everything else I need. The cylinder has only been bored one size up so I can go few more! Haven't decided if I'm going to add the second boost port to this one. I didn't like doing the one on the z jug. https://uploads.tapatalk-cdn.com/20220105/09805ba767c126d8c6f883dd02f906cd.jpghttps://uploads.tapatalk-cdn.com/20220105/d240fb5b6ce7dc4840d1681ec28fa5e3.jpghttps://uploads.tapatalk-cdn.com/20220105/010ad5e383afaf8ade664f2ffb5feb6b.jpg

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