I just read that the "Kerry" method of checking the valves is incorrect and will give false readings. ( Can lobe facing directly away from shim ). They say the correct way is to line up the timing marks according to the manual. My question is if you did check the Kerry way are you erring on the side of safety ( a tad more clearance ), or on the danger side ( less than minimum acceptable clearance ). I would hope that it's the former.
I bet you're asking because you did it the way it is in the video and then got the top end all back together, placed the fuel tank back on, made sure it was all buttoned up and THEN you found out that was incorrect!
I'm not sure if it will make your clearances greater or smaller, but I would get back in there and do it the timing mark way for piece of mind :cheers:
Kerry method is wrong mainly because it involves pulling the shim and putting in a 215 and measuring ... that causes the shim to oil float. Gives you smaller readings than it actually is.
Measure first before pulling anything. Write it down for each valve.
Pull the shim, do the math and put the right shim in. That is it.
Cool.
Buddha.
That's exactly what I did centuryghost, and I don't relish the thought of doing it over.
Buddha, Gsjack was specifically referring to the initial set up for measuring the clearances not replacing shims. I'm just wondering if after doing the Kerry measurement is it going to be in error on the loose or tight side of the spectrum.
I am pretty sure the Kerry method results in larger clearances. Both because of the oil cushion mentioned by the Buddha as well as the lower apparent clearance measured when the cam lobe is away from the shim.
Is the bike running better or worse?
It's running the same, I just don't like not knowing if the clearances are within tolerance.
This is what GSjack said;
" Don't check GS500 valves with the cam lobes set away from the valves, set with engine on timing mark and camshaft notches towards and then away from each other as shown in the manuals to get accurate measurements".
Sorry to say, but get back in there and use the timing mark method. It's actually really easy; set one timing mark, measure three valves. Set it again, measure one valve. Done.
Guess I'll have to if I want "Peace of Mind", that part does sound pretty straight foreword, I'll give it a shot----Thanks!
Quote from: centuryghost on November 24, 2009, 06:22:51 PM
...the timing mark method. It's actually really easy; set one timing mark, measure three valves. Set it again, measure one valve. Done.
In fact it's easier and quicker too, I must say.
If you proceed as per Kerry's, you'll be on the safer side. Tried it myself last time I did my check (one month ago), going Kerry's way the clearances I measured were (a bit) tighter. Going as Haynes manual suggests (timing marks aligned) they were all OK, actually my left EX valve was 0.09 mm, which I decided to leave it as is.
Kerry's method is likely to leave em over 2-3 shim sizes loose. If you're wanting them loose, do it without the oil float method and round it down to the smaller shim.
The cam pointing away etc etc, I have done it all different ways and not had a significant difference.
Cool.
Buddha.
Just to repeat what simon and the buddha say, going Kerry's route will give you a tighter measurement when checking the clearance. The base of the cam is as close to the shim as can be given the way he orients the cam lobe (at a 90 degree angle away from the plane of the shim) when doing the check. You will get the smaller measurement this way as opposed to the method of aligning the timing marks a la the Hayne's manual method, which leaves the cam lobes oriented differently and further apart from the shims. So basically yeah, using Kerry's way will give you tighter measurements, requiring thinner shims to get within the .03 - 0.08mm spec and leaving you with the larger of the possible clearances possible between the two methods.
So, no one every really explained why doing the valve check using the Hayne's method was better than Kerry's. Why when doing it the Hayne's way, each cam lobe seems to be oriented in a different direction, therefore creating varying distances between cam lobes and shims?? Why wouldn't you want each cam lobe to be facing the same way in relation to the shim (as in Kerry's method), therefore ensuring that the gap between the cam lobe and shim for each valve is equal (ideally, before taking into consideration shim thickness)??