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first time doing bike valve clearances - trying to avoid taking the bike to a workshop which will cost me an arm and a leg, and I will never really know if they've done them.

ok I've downloaded the service manual which does walk you through the procedure, but I wanted to get some advice from the experts here first. I'm a car mechanic by trade, so I am familiar with doing valve clearances on cars, but obviously car engines don't typically use shims or have 5 valves per cylinder !

Looking at the service manual, it appears (to a novice like me) like an overly complicated procedure, namely the entire degree wheel on the crank thing. Now on DOHC 4 cyl cars I would turn the engine close to TDC and adjust the crank until valves on #1 were on rock and then move to the opposite cylinder (according to firing order) until the cam follower is sitting on the lowest point of the cam lobe (the base circle). Then I would make the valve measurement/adjustment. Next cylinder the same etc etc.

Now the FZR manual makes mention of finding TDC and then turning crank another 5 degrees then measuring certain valve clearances. Turn the crank another x degrees and measure the next set... Is it necessary to use a degree wheel and follow this procedure ? I only have a degree wheel that I've used for dialing in camshafts on car engines - obviously far too big for the bike. Do the same principles apply to the bike engine as the car in regards to valve clearances ? By that I mean can I just measure the valve clearances based on when the camshaft is running on the base circle of the lobe for each valve ?

or if I've completely lost you all with my confusing description above, could the well seasoned experts please offer me a bit of a run down on how they do valve clearances ?? Do you do it as per the book or do you have a simpler method. And how do you tend to go for a tight 'cold' clearance or a lose fit ? We're almost into summer here in Australia, ambient temp at the moment is typically around 25 deg C/ 77 deg fahrenheit

thanks in advance!

You don't need a degree wheel for any of the procedure

1. First you turn the crankshaft until TDC on l/h no 1 cylinder, there are punch marks on each camshaft next to the cam sprockets and lines on the cam caps when these line up you are at TDC no1, in this position check inlet and exhaust clearances this cylinder.

2. The cam lobes will be pointing away from each other in this position.

3. Turn the crankshaft until the next cylinders cam lobes are pointing away from each other and check clearances (exhaust and intake).

4. repeat for the other two cylinders.

As these engines are shim under bucket the camshafts have to be removed to adjust any of the clearances (by replacing the shim with a different size)

chris

mmm sounds like a job for the experts.and you will also need the spare shims. alot cheaper to pay them than to stuff ya motor $$$$$$$$$$

thanks chris - your explanation is fairly much the same as what I have experienced with DOHC car engine valve clearances.
The FZR service manual obviously overcomplicates things as I suspected.

thanks for the tip on the marks to look out for.


hey willi, nice to see a fellow Aussie here
had I not been a mechanic I would totally agree with you. But I've re-built car engines, had experience checking and adjusting clearances using feeler guages, micrometres, plasti gauge etc. So my philosiphy is a bike engine isn't that different to a car engine, I should be able to do this stuff myself, just need a few pointers from the guys in the know. And I might add it's the only way I'll know it has been done properly.

sorry dude i wasnt judging your ability to do the job i was judging myself there. but i totaly understand where ya comin from wen ya say atleast you no its done if you do it yourself. work shops rip off people every day. and i have been stung once myself. bloody theifs . if i cant stay and wach them do it ,atleast from a distance il go elswere.most of the the easy stuff il do myself minor servicing etc. the old fizzer is the first bike i have come across were ya have to remove the cams, to do the valve clearance. wat a royal pain in the a$$.

no offense taken mate

yeah worked with a few dodgy mechanics in my time - thus my skepticism. Some mechanics understanding of 'adjust valve clearances' is wiping over the valve cover with a rag and replacing the gasket/seal...

problem with valve clearances (particularly on bikes) is you don't know if they have been done or not, until you've burnt out valves.

post some pics of your bike in pics section

yes I will have to do that. Have to find a nice spot to take a photo.

It's basically a stock standard run of the mill red and white 89, with a few minor knocks and bruises. But I love the thing - they are a damn good looking bike I reckon with the go to match.