Newbie to the zephyr life

[blake12345]

Yep that’s it...

[Freddy]

And this is what's inside the engine. The rear guide part # 12053B just pivots freely back and forth in that bottom bracket. It is 100% the tensioner than applies any force against the guide and in turn chain. The chain when tight is the ONLY thing that stops the tensioner from screwing in easily and pushing the guide forward.



So, if you have wound the tensioner right back, and for some reason it won't screw forward with just finger pressure till it takes up the chain slack (by pushing the rear guide forward) then there is something wrong with the tensioner thread or body. As I said previously pull it off and inspect.

[blake12345]

That’s what I thothought!
I’m going to pull it out and see how I go. Do you have to remove the carbs or can you get around it without removing them?

[Richard]

No you don't but it makes inspection real easy if you do...

[Freddy]

That’s what I thothought!
I’m going to pull it out and see how I go. Do you have to remove the carbs or can you get around it without removing them?

I just looked in the Haynes manual which covers both the 550 and 750, and it says for a 550 yes you need to remove the carburetors. It looks like that's purely to gain access so if you can work around them no need (I don't know as I own a 750).

Anyhow, if you have to remove the carburetors don't just see it as a pain, but rather an opportunity to give them a good clean. Will they need it? On the assumption it hasn't been done for year and the bikes probably sat idle for long periods during that time, yes.

[blake12345]

Alright so carbs are coming off and i’ll Take the valve cover off to make sure the chain is tensioned perfectly.... don’t really want too but I thought I better do it properly!!

I’ve got some individual filters laying around should I put these on while it’s all apart? I’ve read on the webs that i’ll Probably need to rejet the carbs is this right? I kind of just want to ride so if it’s something that’ll take more time and parts to do i’ll Just leave it for now

[Freddy]

Alright so carbs are coming off and i’ll Take the valve cover off to make sure the chain is tensioned perfectly.... don’t really want too but I thought I better do it properly!!

I’ve got some individual filters laying around should I put these on while it’s all apart? I’ve read on the webs that i’ll Probably need to rejet the carbs is this right? I kind of just want to ride so if it’s something that’ll take more time and parts to do i’ll Just leave it for now

You can't take the valve cover off, and tension the cam chain correctly. Go back a couple of post and check out the parts schematic I posted. Take note of the cam chain guide #12053 sitting above the chain on the top run between the two camshafts. It actually fits into the valve cover, and the chain slightly deflects around it.

If you remove the valve cover, tension the chain without the valve cover in place, and then refit the cover the tension will then be excessive. The cam chain tensioner can only be set with the valve cover in place.

My advice on pod filters, if you love constant pain, a poor running bike, and have endless hours of free time that you are looking to fill somehow, fit the pod filters. If you want a correct running bike, leave it just how the very highly experienced and qualified engineers at Kawasaki designed it to be. The airbox is not just there to hold the air filter on a CV type carburetor. It is an integral part of the way a CV carburetor works, so much so that it should be seen as a part of the carburetor. No amount of a changing of fuel jets can correct the problems introduced if it is removed. An airbox is designed to boost performance, there is a reason MotoGP bikes and F1 cars use em.

If at some point down the track you do want to do something to improve performance ....... if you live at sea level in a temperate or cool environment than I think you could confidently fit one size bigger main jets. But I wouldn't even recommend that till you got the bike running 100% perfect and spent some time on it to establish a firm 'benchmark' in your mind of stock performance. Unless you do than you'll never be able to objectively assess if any change has actually made an improvement or otherwise. And NEVER make any change that can't simply be reversed.

[blake12345]

I thought I remembered reading in the service manual (I don't have it on me right now so cant say for sure) there is a deflection amount on the chain when it is tensioned that can be measured when the valve cover is off... I could be wrong, which I probably am...

As for the air filters I will leave them off. I just found them in some boxes in the garage and thought if it was a simple add on id do it.. I understand the engineering of air box but coming from a modified car background there are many products out there that have been engineered and proven to give gains in performance, reliability etc. But that's why I come on here to ask the questions so I don't make mistakes that you guys have already looked at.

[Freddy]

I thought I remembered reading in the service manual (I don't have it on me right now so cant say for sure) there is a deflection amount on the chain when it is tensioned that can be measured when the valve cover is off... I could be wrong, which I probably am...

As for the air filters I will leave them off. I just found them in some boxes in the garage and thought if it was a simple add on id do it.. I understand the engineering of air box but coming from a modified car background there are many products out there that have been engineered and proven to give gains in performance, reliability etc. But that's why I come on here to ask the questions so I don't make mistakes that you guys have already looked at.

You could probably make up a jig of some sort to replicate the deflection of the guide in the valve cover, but I think it would still be highly problematic. Just the wear in the guide and the thickness of the valve cover gasket would significantly affect the accuracy of the jig. If the manual tensioner main bolt is running perfectly freely its way more accurate to set the tension with your fingers on that bolt. You then just back it out a 1/4 turn to give it the tinniest amount of slack account for any out of roundness that may exist at some different point between the crankshaft and cam gears.

Not aware of any cars that run a modern CV carby. It is a unique design that relies on a specific small pressure differential between the intake and internals of the carby to appropriately alter the height of fuel in the emulsion tube in response to engine operating conditions. That's how it can function without an accelerator pump which is an essential part of just about every other carby design. The design of the airbox maintains that critical pressure differential. The closest to my knowledge of a CV used on cars was the old SU used on many English vehicles. Weren't they just a pain to tune, just one of em, let along a whole bank of em.

[blake12345]

I'll pull the tensioner out and make sure its turning smoothly.

I wasn't necessarily talking about CV carbs on cars was just referring to aftermarket parts in general.

When I had a car with multiple SU carbs I found an old mechanic who turned the car by ear.. it was amazing to watch him tune the carbs with just a screwdriver and the car ran amazing after he was done with it.