kz750e Resto-Mod

GPzMOD750 wrote: What sprockets are you using?

I'm curious as well about your gearing. The 550 has a lower first gear compared to the 750 so moving to a taller final drive makes sense with the bigger engine.

I'd also like to hear your view on engine vibration. As I understand it Kawasaki added rubber engine mounts as the years advanced; first rubber on the front only and then both front and rear. My own 750 with hard mounts is remarkably smooth, which is one of the things I like about the bike. I wouldn't mind overboring to 810 though, but not if it adds vibration.

I'm using a 17-t front and 39-t rear with a 530 chain.
Because of my Zephyr swingarm, I needed to use the biggest 530 front sprocket I could fit (which is 17-tooth) so I could keep the chain from sawing through the swingarm pivot.
I had gone up one tooth on my front sprocket to reduce high speed rpm's on my zr550, but at the expense of low speed performance around town. So the only benefit of switching to the 6-speed is that I got to keep the stock gearing and add an overdrive, thus letting me get much lower rpm's on the highway without sacrificing any low speed speed performance.
You are correct to question everything I post, as this mod may not make sense for anyone. And partially the reason I did this, is because I wanted to see how it was done and if I could do it. As I stated in my very first post on this build, this is my own self taught shop class. So I had to challenge myself to see if I could learn something.

My zr550 also has the rubber isolator engine mounts on front and back, but it still vibrates like crazy. Part of the reason I wanted to lower the high speed rpm's because it would make my hands and feet numb at high speeds.
So far my 750 has nothing like that, and as you mention Nessism, it is remarkably smooth.
But on the newer Zephyr 550 and 750's, and zr-7's they no longer used a lower engine mount in the front, so maybe that has something to do with why they went to rubber mounts? Or not??

Hows she run with the pods DR, I have a mate who races a GPZ 750 {810}, he has the stage 3 dynojet kit with pods and he says it runs great, he's trying to talk me into doing the same with mine, I'm a big airbox fan, especially with the CV's, but Terry says not only is his bike running great, its far easier to get to the carbs if he needs too. I'm interested to hear your opinion... Love the bike...

I'm running with 16/38 530 sprockets which is supposed to give 2.34 final ratio. I had to go back through my first project thread and check.

I wonder if I should go up on the front or the back.... I know there are some sprocket calculators around. I guess I should have a look.

I really appreciate you posting all this great info. Even if it doesn't turn my bike into the wonder-cycle I'm still putting in the gear box if only for the "cool factor", a 35 yr old 3/4l with a 6 spd. The close ratio 2-4 gears ought to be fun in the canyons too.

750 R1 - I am forced to use the pods as there is no room for the factory airbox now that I have the zr550 battery tray and electronics crammed in there.
In my limited road testing, It seems to run perfectly so far with the pods. I am using the Factory Pro Stage 3 jet kit for the Zephyr zr750 that requires no drilling of the slides (which there is no going back from) But it took a lot of trial and error to get there.
I had previously run pods on my zr550 that also uses the keihin cvk carbs. I had also used a Factory Pro Stage 3 kit specially made for the zr550 and it worked fantastically until I tried to cruise at highway speeds.

Rather than retype it all, here is a excerpt I copy and pasted from the zephyr-zone.com forum which explains my issues and solutions.

"My reasons for switching to pod filters was for many reasons:
1. I was to inexperienced to know better.
2. My airbox boots were hard as a rock. When removing or installing my carbs when I first tried to get it running was a nightmare. I even knocked the bike off the side stand onto myself trying to wrestle the carbs on the boots once.
3. I found the K&N filters on Amazon for a third of the price of new airbox boots.

The first thing I did was purchase a Factory-Pro stage 3 jet kit (negating the savings of the air filters) and installed it according to the directions they listed for pod filters and a stock exhaust. Around town was fantastic. Any speed above 60mph it was unridable.
The issue that people time and again state, is that CV carburetors must not have any positive air pressure going into the intake side. When the carb has air forcefully blown into them rather than the carbs drawing in air at their own “pace”, the vacuum diaphragm controlled slides shoot up and dump to much gas into the engine causing it to bog down. Pod air filters flow to well and allow to much cross wind air into the carbs and at high speeds the air is actually forced into the cabs like you were pointing a leaf blower at them.
My first solution was to wrap my filters with vacuum filters. As described in this thread:
www.zephyr-zone.com/cgi-bin/yabb2/YaBB.pl?num=1349470533/6#6

Last spring, the vacuum filters did not survive me removing them for cleaning, so I had to come up with a new solution. This time I made baffles to go inside the pod filters themselves to “shelter” the carbs intakes (where the vacuum intake for the slides are) from the onslaught of air coming in. I got the idea from some people using velocity stacks inside of pod filters to redirect the air coming in.
I made the baffles from the cans of the beer I was drinking at the time when I got the idea.
They were incredibly easy to make using only a pair of scissors, rivet gun and a single-hole paper punch. I made the length of the baffle so it starts at the mouth of the filter and seals tightly against the rubber back end of the filter, so the air has to go through the holes and can’t rush in the end of the baffle. I made sure to punch enough holes in the baffle so as not to starve the carbs of air and my unscientific tests I did showed no restriction in flow rate between a baffled and un-baffled filter.
The baffled filters work flawlessly with the Factory-Pro jet kit and It pulls hard from idle to redline and cruises smooth as glass no matter how fast I’m going."








I needed to drink the beer as fast I could so I could use the empty cans to make the baffles, so by the fourth can my craftsmanship was really starting to suffer. (that is the one pictured.) I was doing really unscientific tests with using a vacuum cleaner to suck air through the filter with and without the baffle. When the vacuum stopped struggling and was using the same amount of "effort" to suck air through the baffle as the it did without it, I stopped punching holes in the baffle. I wanted just enough resistance to stop the "cross wind effect" but to not starve the engine of air.
It works, but velocity stacks area more elegant solution to the cross wind issue. But they are way more expensive than a 4-pack of Murphy's Stout.



GPzMOD750 - Gearingcommander.com is what you need to use to figure out what sprockets to use with the 6-speed and see if you will get the numbers you want. That way you can calculate it with the exact rear tire size you are using...etc. It is less typing to load up the gearing for a kz/zr/gpz550 and then change the primary gear ratio to 2.55 and then your tire size and then go from there. You will need to get a new front sprocket at the very minimum, or you will need to convert it to the "keeper" style that the 550 transmission uses. The 17- tooth is the largest 530 sprocket that will fit without having to do away with the chain guard on the output shaft cover.

Daftrusty wrote:
My zr550 also has the rubber isolator engine mounts on front and back, but it still vibrates like crazy. Part of the reason I wanted to lower the high speed rpm's because it would make my hands and feet numb at high speeds.
So far my 750 has nothing like that, and as you mention Nessism, it is remarkably smooth.
But on the newer Zephyr 550 and 750's, and zr-7's they no longer used a lower engine mount in the front, so maybe that has something to do with why they went to rubber mounts? Or not??

Oddly, the old solidly mounted engine KZ550's don't buzz like the rubber mounted engine ZR550's

Thanks DR, I'm familiar with all the different mods made to pods to try make them work, apparently you can buy K&N pods with velocity stacks inbuilt..? Using stacks is definitely a good idea, anything that smoothes out turbulent, incoming air into a laminar flow is highly beneficial. Wasn't there a member here a while back that made stacks that could be used with pods, I remember reading something a few years back about it, way before I became a member here, a member named "Dutch" maybe...? I've seen some pretty interesting compromises for lack of room for air boxes, I've seen a couple where the carb mounted section of the box is retained, the whole rear section removed and a single large {or what ever size will fit} pod used, I plan on doing something similar to this on an old 750 Honda, using a completely gutted airbox with a pod mounted at the rear of the box for filtering, just to gain more volume in the airbox. There's always something to keep the head spinning....

I had read probably the same thread years back of a guy on here who milled his own velocity stacks to go in his pods.
That is exactly what gave me the idea to try something along the same lines.

Daftrusty wrote: I had read probably the same thread years back of a guy on here who milled his own velocity stacks to go in his pods.
That is exactly what gave me the idea to try something along the same lines.

Cool, as long as it works... Have you decided on a color scheme for your 750 yet..?

You got it right. Dutch had Wompy (another member here) at Still Kicking Moto make the stacks. Wompy made a few sets and i have a set i am going to run on my KZ1000. No clue how they actually work yet.

If my super ghetto beer can baffles work, then the velocity stacks have to work.

I am mostly dead set on the old dark navy blue color with the kz1000 mkII gold and white pinstripes. But apparently nobody knows the exact paint formula to match the vintage color.
But now that it is in grey primer, I am almost thinking that it would look good in silver. Silver is my favorite car color, because it looks clean even when it is dirty, and I like how it contrasts with the black on the bike. I am worried that the dark blue paint and black everything else will be just to dark. But I also don't think the factory pinstripes will look good on the silver.
My bike was silver from the factory before the previous owner spray bombed it black, so it might be neat to make it silver again.

When it was new


More of a champagne silver, but you get the idea


As it is now


I don't know if the pinstripes are wonky or if they are the wrong color, but this doesn't look good.

Blue...... We'll get something that works