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Z650 Special Revisited

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LeeJackson
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Re: Z650 Special Revisited

#16 PostAuthor: LeeJackson » Sun Feb 02, 2025 10:29 pm

Today not a lot happened but I did make a bracket for the clocks. First pass looks aweful way too high… second is back in line how it should be.
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LeeJackson
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Re: Z650 Special Revisited

#17 PostAuthor: LeeJackson » Sat Feb 08, 2025 10:28 pm

Had a helper today so got the 750 lump in it. Next spacing out chains…
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dixiethedog
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Re: Z650 Special Revisited

#18 PostAuthor: dixiethedog » Sun Feb 09, 2025 11:45 am

Nice progress. Will you have to use an offset front sprocket to get the chain aligned?
From memory I am sure that the Gpz750 came from the factory with an offset sprocket which could be a good help. But I think they came in a heavy 630 chain size? I think as well that when I had a ZZR11D model that the front sprocket on that was offset as well.
Keep the pictures coming! :D
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Re: Z650 Special Revisited

#19 PostAuthor: Hard Road » Sun Feb 09, 2025 6:17 pm

looking good Lee :wink:

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Re: Z650 Special Revisited

#20 PostAuthor: LeeJackson » Sun Feb 09, 2025 7:09 pm

dixiethedog wrote:Nice progress. Will you have to use an offset front sprocket to get the chain aligned?
From memory I am sure that the Gpz750 came from the factory with an offset sprocket which could be a good help. But I think they came in a heavy 630 chain size? I think as well that when I had a ZZR11D model that the front sprocket on that was offset as well.
Keep the pictures coming! :D


So I got onto the alignment today and realized that not only did I not have an offset front sprocket but I also didn’t even have any front sprockets. So I don’t have much of a starting point. I’ve done a load of GPz stuff and broken a few motors but guess I binned the sprockets because who would ever want a used front sprocket. Haha. So I’m going to hazard a guess with some advice from you guys hopefully.. :) I know I’ll need to machine the carrier a bit but anyone know what the max offset o can go to without fouling the frame is by chance? I will stick with a 530. Thanks!

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Re: Z650 Special Revisited

#21 PostAuthor: LeeJackson » Sun Feb 09, 2025 7:17 pm

Since I was stuck on the sprocket alignment I thought I’d have a dog in the loft for an Exhaust. Found a sawn off laser 4-1, put it on and looked aweful.. then I found my old V&H megaphone.. now that’s better! Bit rusty but I’m sure it will polish up a good bit.

This one I’m going to give to my mate who loves polishing, he’s just given up drinking too so good time to get him as he’s always needing to keep busy :lol:
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Hard Road
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Re: Z650 Special Revisited

#22 PostAuthor: Hard Road » Sun Feb 09, 2025 7:24 pm

LeeJackson wrote:
dixiethedog wrote:Nice progress. Will you have to use an offset front sprocket to get the chain aligned?
From memory I am sure that the Gpz750 came from the factory with an offset sprocket which could be a good help. But I think they came in a heavy 630 chain size? I think as well that when I had a ZZR11D model that the front sprocket on that was offset as well.
Keep the pictures coming! :D


So I got onto the alignment today and realized that not only did I not have an offset front sprocket but I also didn’t even have any front sprockets. So I don’t have much of a starting point. I’ve done a load of GPz stuff and broken a few motors but guess I binned the sprockets because who would ever want a used front sprocket. Haha. So I’m going to hazard a guess with some advice from you guys hopefully.. :) I know I’ll need to machine the carrier a bit but anyone know what the max offset o can go to without fouling the frame is by chance? I will stick with a 530. Thanks!


you will gain a few more mm's if you go to a 525 or even a 520, plenty strong enough if you but a decent chain.

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Re: Z650 Special Revisited

#23 PostAuthor: dixiethedog » Sun Feb 09, 2025 7:34 pm

Did zed1015 not touch on sprockets with his 2 wonderful builds in the project section? Always worth a look. :D
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Re: Z650 Special Revisited

#24 PostAuthor: dixiethedog » Sun Feb 09, 2025 7:43 pm

It is worth having a look on the kz riders forum. In the search engine thing type "offset sprocket" then look in chassis section and you will find page after page of threads talking about sprockets. :D
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LeeJackson
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Re: Z650 Special Revisited

#25 PostAuthor: LeeJackson » Sun Feb 09, 2025 7:57 pm

Yeah I guess smaller is even an option, not exactly going to be getting hundreds of hp thru it :) I’ll have a search tonight, see what I can find.

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Re: Z650 Special Revisited

#26 PostAuthor: Hard Road » Sun Feb 09, 2025 8:09 pm

LeeJackson wrote:Yeah I guess smaller is even an option, not exactly going to be getting hundreds of hp thru it :) I’ll have a search tonight, see what I can find.


I used a 525 chain kit on a Zed i built with a bandit 1200 engine in, give it some stick with no issues. also you will find 525 and 520 on race bikes.

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Re: Z650 Special Revisited

#27 PostAuthor: LeeJackson » Sat Mar 08, 2025 7:38 pm

My mate did a grand job for me on the pipes. Looking totally presentable which was all I need on this build. Got my front sprocket on too with the 5/8” offset which should just clear the frame. Now a bit of measuring and a few mil in at the back and we’re good.
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Re: Z650 Special Revisited

#28 PostAuthor: LeeJackson » Sat Mar 08, 2025 7:45 pm

Need to think about carbs soon. I’ve a choice of CVs from a GPz750 or a set of 650 24s… opinions welcome on what to use :)

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Re: Z650 Special Revisited

#29 PostAuthor: warren3200gt » Sat Mar 08, 2025 8:02 pm

Vm24ss. Easy to tune ane more than enough air capacity for even a modded motor.

Z650
Vm24 dia = area 452mm sq x 4 = 1808mm sq div by 652cc = 2.77mm sq per cc.
Z900
Vm26 dia = area 531mm sq x 4 = 2124mm sq div by 902cc = 2.35mm sq per cc.
Z1000
Vm26 dia = area 531mm sq x 4 = 2124mm sq div by 1015 = 2.09mm sq per cc.

Up jet to suit any mods.
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LeeJackson
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Re: Z650 Special Revisited

#30 PostAuthor: LeeJackson » Sat Mar 08, 2025 8:24 pm

warren3200gt wrote:Vm24ss. Easy to tune ane more than enough air capacity for even a modded motor.

Z650
Vm24 dia = area 452mm sq x 4 = 1808mm sq div by 652cc = 2.77mm sq per cc.
Z900
Vm26 dia = area 531mm sq x 4 = 2124mm sq div by 902cc = 2.35mm sq per cc.
Z1000
Vm26 dia = area 531mm sq x 4 = 2124mm sq div by 1015 = 2.09mm sq per cc.

Up jet to suit any mods.


Great advise thanks! I was wanting to use the 24s was just a bit worried they might not be enough for the bigger motor. But clearly are! They will be getting a work over next!


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