ZX9R 2000 Valve clearances

Slow and wobbly · Post by **Slow and wobbly** » Mon Jan 29, 2007 9:37 pm

Since I have owned my 9 ( 5 years ) I have done all my own servicing regularly at 5000 km intervals but I have not yet attempted valve clearances. The bike currently has 52 500 kms on the clock and last had the clearances checked by a shop at 25 000 kms with only 2 shims having to be swapped out. The owners manual states that they should be checked every 24 000 Kms and as such it is now due to be looked at. I was going to stretch this out until I could find the time to get it down to BK, since I live about an hour from there and the bike needs to be cool when the clearances are checked this presents me with the hassle of getting it down there and picking it up on seperate days. So I have made the decision that its about time I learnt how to do this.
At the moment the bike has a distinct lack of power. I have a mate with the same model and in top gear roll ons he just walks away form me, I cant lift the front wheel in first gear off the throttle and I am definitely working the gearbox alot more trying to find drive out of corners. All this just wont do!
In an effort to rectify this situation this week I am going to
1. Adjust and correct valve clearances ( what I believe to be the source of the problem )
2. New set of plugs ( last changed at 35000 )
3. Clean and balance the carbs
4. replace clapped out chain and sprockets ( last changed at approx 28 000 )

So........ If anybody has any experience with having checked and adjusted valve clearances could you please read through the below link to a site I found and tell me if the information given is good or bad, I thought it read ok and contains scans of the workshop manual so it couldn't be too bad a reference. Irrespective of wether this solves my problem or not they are due to be checked and it would then allow me to rule it out and start searching in other areas for my lack of power.
http://www.ovrlnd.com/9RValveCheck/ZX9ValveCheck.html
Thanks
Adrian

Oh and for those reading along with an interest here is another link I found for a broader understanding of the importance of valve clearances.
http://www.wgcarbs.com/269767.html

Rossi · Post by **Rossi** » Mon Jan 29, 2007 10:13 pm

I thought I posted this one before ??

http://www.calamarichris.com/zx9r/valveadj1.htm

Slow and wobbly · Post by **Slow and wobbly** » Mon Jan 29, 2007 10:42 pm

I did do a search of the site but this didn't turn up then. Thanks anyway for putting it up again.

Post by **Wattie** » Tue Jan 30, 2007 6:20 am

i used the link rossi posted on my Z,
went well, if used in conjunction with a workshop manual.

mine were all good

must be my riding thats slow... not the bike

Strika · Post by **Strika** » Tue Jan 30, 2007 9:01 am

Valves arn't that hard, just time consuming to get everything off and back on again, so people tend to shy away from it. In reality, it's just pulling stuff apart and bolting it back together. Don't forget you will need a torque wrench to do the cam caps. Measure twice and shim once is also a top recommendation S n W. I have done a few of these over the years including mine, so if you would like, and I'm home, you can lob over and do it here. I'll supervise and make sure you don't feck anything up. Mind you, by the sounds of your post, you are plenty capable to do this little job on your own.

photomike666 · Post by **photomike666** » Tue Jan 30, 2007 4:06 pm

Is this just a little too clean? He's claiming 38,000miles (60,000km+) and it looks nicer than a Haynes Manual. Is he a little retentive about his cleaning, or am I just a mechanical slob?

Post by **Wattie** » Tue Jan 30, 2007 4:20 pm

he's pretty damn finatical hey mike!!

he cleans inside his spark plug hole things with a cotton bud

and he wears gloves...

theres nothing more manly that having your hands all oily and smelling like engine bits

Slow and wobbly · Post by **Slow and wobbly** » Tue Jan 30, 2007 9:29 pm

Tonight I have stripped and cleaned the carbs and measured the clearances. As far as this guys instructions go they are pretty good and a very helpful reference, however it is useful to use both links. As stated above it is best used in conjunction with a manual of which there are scanned copies of the relevant pages in the first link I posted.
I actualy stripped everything back to the rocker cover last night and so tonight I was able to get a start on the carbs. Now as far as my bike goes it was once my only form of transport for the about 3 1/2 years and it was used every day, but since I acquired a company vehicle 18 months ago it has now gone into semi retirement. In the last 18 months I have only clocked up 4500 k's through weekend use. the reason for me explaining all this? Well if you look at the pics below you will see a build up of goop on the blue thing* caused by the fuel in the carbs sitting stagnant and evaporating and leaving behind this varnish. The bowls also contained this brown molasses type stuff, however there wasnt any water in the bowls and overall the carbs were quite clean. In one of the pics below you can see the diaphram of one of the carbs refusing to sit back down where it is supposed to. I contribute this to the CRC Clean-A-Carb stuff I used and I think it caused it to swell a small amount. Live and learn - it eventualy was coaxed back into place - but from now on I think I will stick with shellite for this job, never had any probs with that.

As for the valve clearances well I spent alot of time checking and re-checking ( I think I checked each one over 6 times ) I am a little overcautious given this is the first time I have done this and it is clearly not something I want to make a mistake with $$$$$$.
So an hour and half of fiddling and checking the clearances I have settled on these figures;

x 0.14 x 0.24 x 0.26 x 0.27 x 0.20 x0.24 x 0.21 x 0.21

i 0.15 i 0.15 i 0.19 i 0.16 i 0.18 i 0.20 0.19 i 0.19

Now the tolerances stated in the manual are;
Inlet 0.15 - 0.24
Exhaust 0.22 - 0.31

I am yet to remove the cams to measure the shims as quite frankly I am rooted right now and I haven't got the concentration tonight to go any further. But from looking at these figures you can see clearly the first exhaust clearance is a reasonable way out and all of the others are at the lower end of the tolerance scale. The number one thing in my mind at the moment is this, if I am to start changing shims what clearance is ideal? High end of the tolerance scale, middle or low and since I am at this stage can I optimize power by aiming to achieve an exact clearance on all of the shims? or would I be wasting my time because they will all vary wildly again after the first 100 ks?
Thanks for all comments so far
Adrian

* --- I realy dont know what its called, I just know where it comes from and how it goes back together ---

bonester · Post by **bonester** » Tue Jan 30, 2007 9:37 pm

Your worn chain and sprockets could easily cost you 10 horsepower, believe it or not!

Slow and wobbly · Post by **Slow and wobbly** » Tue Jan 30, 2007 10:04 pm

Yep I am aware of lost horsepower through the drivetrain. Its on the hit list! Also while I am in the top of the engine at the moment I looked down at the plugs and see a fair amount of corrosion on them , they are next after the valves have been sorted. One thing at a time and no big hurry. Basicaly looking to restore all the power I had, then start building on more.

Oh and this seems to be a great way of getting the bike inside the house too! She once said there was no way in hell I could bring the bike into the lounge room, but at the moment all the bodywork and bits and pieces have been brought inside away from her chewing machine she calls a dog. I was wondering if I could over the next few weeks dismantle the bike, bring it inside and re-assemble it before she realizes whats happening

Strika · Post by **Strika** » Wed Jan 31, 2007 7:04 am

S n W said...."if I am to start changing shims what clearance is ideal? High end of the tolerance scale, middle or low and since I am at this stage can I optimize power by aiming to achieve an exact clearance on all of the shims? or would I be wasting my time because they will all vary wildly again after the first 100 ks?"

I would always set the clearances up at the loose end of the scale. You will know this stuff for sure by the looks of you mechanical confidence, however for those that might want to know.......Vavles will stretch as they wear, thus closing up the valve clearance (we are talking about the minute gap between the cam lobe surface and the top of the valve actuation..in this case a bucket with a shim under it.). Also, they will receed into the head slightly over time. They cop a fair old bashing at 10,000rpm remember.

So my suggestion is to set them up right at the loosest end of the scale. Also from experience, 9's and 6's make a little more power with looser clearances.

leadbelly · Post by **leadbelly** » Tue Feb 06, 2007 2:52 pm

We haven't heard from Slow and Wobbly for a while, so I expect this post may be a little late to help. Have you finished the job?

I did the valve clearances on my ZX9 F1 this time last year at 24,000kms - a bit of a daunting job at the time - although I'd done the same job on a KLX650R it's a much easier job on the single.

I had to change/swap most of the shimes - exhaust down 2 sizes and inlets down 1. I saved money by sourcing the shims from chris@precisionshims.com.au. Not only are his 7.5mm dia shims half the price of the Kawasaki parts, but he can supply the half size increments for more precise adjustment - but you have to be good and consistent measuring with feeler guages to really take advantage of this.

Strika is right - it's best to set the gap at the upper end of the tolerance. Clearance tends to shrink over time, but it's not through valve stretch, but through gradual valve seat and face erosion/ wear. Also, setting clearances toward the lower limit will tend to increase top-end power as the valves will be open slightly wider and longer, so should flow more mixture. But lets face it a healthy ZX9 has more than enough power for most of us and a wider setting will stay within tolerances for longer.

BTW I did the same job on my CB1300 for the first time last month at 48,000kms - the middle 2 cylinders had perfect clearances, but 2 exhaust valves and 1 inlet on the outer cylinders were 1 thou below the lower tolerance, but I decided to wait until the next check (maybe 70,000km) before I disturb the cams and make any changes. I figure that, compared to the ZX9, the CB is revved a lot less, has very mild cam timing and low compression. The CB is a little more difficult to do than the 9 - it has a central cam chain run and uses a hydralic cam chain tensioner which makes locking the cam chain on refitting the cams more of a problem - you need a third hand.

Strika · Post by **Strika** » Tue Feb 06, 2007 4:40 pm

leadbelly wrote:We haven't heard from Slow and Wobbly for a while, so I expect this post may be a little late to help. Have you finished the job?

I did the valve clearances on my ZX9 F1 this time last year at 24,000kms - a bit of a daunting job at the time - although I'd done the same job on a KLX650R it's a much easier job on the single.

I had to change/swap most of the shimes - exhaust down 2 sizes and inlets down 1. I saved money by sourcing the shims from chris@precisionshims.com.au. Not only are his 7.5mm dia shims half the price of the Kawasaki parts, but he can supply the half size increments for more precise adjustment - but you have to be good and consistent measuring with feeler guages to really take advantage of this.

Strika is right - it's best to set the gap at the upper end of the tolerance. Clearance tends to shrink over time, but it's not through valve stretch, but through gradual valve seat and face erosion/ wear. Also, setting clearances toward the lower limit will tend to increase top-end power as the valves will be open slightly wider and longer, so should flow more mixture. But lets face it a healthy ZX9 has more than enough power for most of us and a wider setting will stay within tolerances for longer.

BTW I did the same job on my CB1300 for the first time last month at 48,000kms - the middle 2 cylinders had perfect clearances, but 2 exhaust valves and 1 inlet on the outer cylinders were 1 thou below the lower tolerance, but I decided to wait until the next check (maybe 70,000km) before I disturb the cams and make any changes. I figure that, compared to the ZX9, the CB is revved a lot less, has very mild cam timing and low compression. The CB is a little more difficult to do than the 9 - it has a central cam chain run and uses a hydralic cam chain tensioner which makes locking the cam chain on refitting the cams more of a problem - you need a third hand.

You are correct, it is recessing into the head. However, it is also valve stretch. I of all people know. I have and do again now, race an F model ZX6. It is one of the things we check everytime we strip the top end for a freshen up. And more often than not, there are quite a few which need changing!

They are well known for it!

Slow and wobbly · Post by **Slow and wobbly** » Tue Feb 06, 2007 8:34 pm

yeah well as usual another thing I have started out in the garage and had to put aside half completed for the moment. As above I have checked all the clearances and found some shims need replacing, what I haven't found though is bloody time. the last week has been hectic and before I remove the cams and measure the shims I first need to acquire a torque wrench to replace them and I need a couple of hours uninterupted. So possibly this week....fark its tuesday night already!
Thanks for the input so far guys, much appreciated.
Hows this for a thought though? what if the inlet clearances were set at the low end of the tolerance scale and the exhaust at the high end? Would this alter the cam timing in such a way to give greater inlet, and maximum duration before the exhaust opens? Or would the difference be so miniscule so as to not notice the difference? [/b]

Strika · Post by **Strika** » Tue Feb 06, 2007 9:16 pm

Slow and wobbly wrote:yeah well as usual another thing I have started out in the garage and had to put aside half completed for the moment. As above I have checked all the clearances and found some shims need replacing, what I haven't found though is bloody time. the last week has been hectic and before I remove the cams and measure the shims I first need to acquire a torque wrench to replace them and I need a couple of hours uninterupted. So possibly this week....fark its tuesday night already!
Thanks for the input so far guys, much appreciated.
Hows this for a thought though? what if the inlet clearances were set at the low end of the tolerance scale and the exhaust at the high end? Would this alter the cam timing in such a way to give greater inlet, and maximum duration before the exhaust opens? Or would the difference be so miniscule so as to not notice the difference? [/b]

Clearance is clearance, so unless it closed to the point where it was actuating the valve, then probably not. But it could cause the valve to not seal properly and burn out...even an inlet valve!