Big Bore Z1

I am an absolute new guy when it comes to this bike and this site but I love forums for their wealth of information. I am looking to surprise someone in my family by getting their KZ running after about 27 years!!!

Here's what I know

- They were in the process of extending the swingarm (needs welding)

- It was bored out (1200)?

- I'm not 100% sure yet what year or model it was but as the title says i think that's what it was originally.

- I have only a few days to actually do the work.. but I do have a couple of weeks to plan out what i'm going to do.

- I am trying to get pics up(it's 10 hours away right now)

I am hoping there are some people who are willing to see this through as I know that there is a ton of knowledge that would be very valuable to me in trying to get this gift back into the family.

I will be checking this thread constantly to try to keep it going.

other than welding the swingarm.. what else do you think i will need to do to get this running?? full carb rebuilds??

Thanks for any and all comments

Kyle

Welcome to KZR, The carbs will need a good cleaning at the least. you should check the valve clearances too and do a compression test to see where the cylinders are.

Mark

quick question.. is it even possible to bore a 900 to 1200?? or am I dealing with a 1000?? and when it comes to extended swingarms.. are there common trends? like aluminum swingarms? just wondering what i'll be welding on. Thanks for the quick replies

900 or 1000 can be bored to 1197 with aftermarket sleeves,got a picture of swingarm?

Kyle_w11 wrote:

quick question.. is it even possible to bore a 900 to 1200?? or am I dealing with a 1000?? and when it comes to extended swingarms.. are there common trends? like aluminum swingarms? just wondering what i'll be welding on. Thanks for the quick replies

It is a 1000. The trend lately is to put a gs110e swingarm on. It's a pretty easy swap but you might not have enough time to find one on ebay, have it shipped then figure out all the parts you need for the swap.

The deal is that the swingarm was previously extended but they didn't finish it.. so there is some more welding to be done.. and I think it may be aluminum? keep in mind this would have been done 15-20 years ago

no pics yet.. i'm 600 miles away but i will try to get someone to take pics for me or i'll get them soon

Alright.. so i got a little more info and i'm hoping someone can help me.

- The bike, when put away, was in pristine condition

- It is definitely a '76 KZ 900 with a 1200 Big Bore Kit.. which was installed and i'm pretty sure it was barely broken in.

- The extended aluminum Swingarm is from a GS 1100.

So My questions are..

Can anyone, without pics.. make an educated guess as to what Carbs were installed with the Big Bore?

I will be going up to see the bike for the first time next weekend so I will definitely get pics put up to make things a little easier.

Thank you very much for any help or comments!

Kyle_w11 wrote:

Alright.. so i got a little more info and i'm hoping someone can help me. The bike, when put away, was in pristine condition. It is definitely a '76 KZ 900 with a 1200 Big Bore Kit.. which was installed and i'm pretty sure it was barely broken in. The extended aluminum Swingarm is from a GS 1100. So My questions are.. Can anyone, without pics.. make an educated guess as to what Carbs were installed with the Big Bore? I will be going up to see the bike for the first time next weekend so I will definitely get pics put up to make things a little easier. Thank you very much for any help or comments!

Can anyone, without pics.. make an educated guess as to what Carbs were installed with the Big Bore?

Possibly Mikuni 29 smoothbores, or maybe Mikuni 33 smoothbores.

Good Luck!

seeing how it was built 23 years ago it could also have 31 or 33 cr's on it as well or even 34 or 36 mikunui flat slides on it as well.

Thanks everyone for the replies. I realize this is an old thread but nothing has changed since then. Except for the fact that the bike is now in my garage for one month and I want to get this in working order in that time. The bike is a 1976 Z1 with a big bore kit put in.. There are, however, a few missing parts here and there but with your help and my incoming manual I will get it figured out.

Here are some pics of the beast.





Aftermarket coils.. is something other than the stock battery needed?



Swingarm..



Carbs.. any help? the intake O.D. is 42.5 mm





Missing a bunch of bolts for the chain guard. What else is supposed to bolt in there? I have the cover and gasket. None of the bolts though.



Aftermarket Header.. assuming it's a kerker



Also, I'm uneasy about putting pod filters on it as it did 27 years ago. However, all of the stock air intake parts are a goner so i might have to keep it this way. What I need to know most it.. what carbs are those? also, these jugs have the 903 stamped on them but like i said they were bored.. what are the possible big bores to that? how can I tell if the head has been replaced? Any and all help will be appreciated.

Thanks!

Kyle