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setting valve clearances
Posted: Tue Mar 12, 2013 12:22 am
by coops
Do i need any special tools and how do i turn the motor? My manual sez something about a dowel pin that goes in the end of the crank for timing. But my pictures are bad (downloaded) i cant make them out.
Cheers, Steve.
Re: setting valve clearances
Posted: Tue Mar 12, 2013 2:17 am
by DonTZ125
There is a special wrench-ish tool, but not many 1k owners have one. Since the plugs are out it shouldn't be that hard to turn over. If it doesn't want to cooperate, you can lift the back, put it in gear, and spin the rear wheel.
Re: setting valve clearances
Posted: Tue Mar 12, 2013 6:30 am
by Conrad
If you take the cap off that covers the end of the crank, you will see it has timing marks on it ( you will probably need a torch to see it though).
You start by turning the motor so that cylinder 1 is at tdc, then set the valves. rotate 180 degrees till you see the next set of marks line up, showing cylinder 2 is at tdc, set the valves and so on.
Turning the wheel while the bike is in gear is the easiest way to turn the motor over.
Re: setting valve clearances
Posted: Tue Mar 12, 2013 3:52 pm
by coops
Thanks guys. No doubt il have more questions when i actually get round to doing it. Cheers
Re: setting valve clearances
Posted: Thu Mar 14, 2013 12:20 am
by coops
So ive checked clearances. I have the clutch out (needs springs and frictions) so i was turning by hand with clutch basket. Worked good.
All the exhaust valves are bang on halfway in tolerance but some intake clearances are on the small side, and two intake clearances are smaller than my smallest .05mm feeler gauge leaf. 56k probably never been set before. So i have valve reccession. Cams look great (if that means anything)
So really, my best bet is too do a compression test?? No point in setting valves if ive got burnt intake valves. I didnt do comp test because my tester wont do those small plugs!
Is intake valve ressesion normal? I should do a compression test before i go any further eh?
Re: setting valve clearances
Posted: Thu Mar 14, 2013 1:13 am
by DonTZ125
It's apparently rather common, if you're having hard start issues, for one or more intake valves to be too tight to measure. All you can do is swap in smaller shims and try to get a measurement. If you're lucky, it's in spec, otherwise you get to do the math and swap in another shim.
There's no point in doing a compression or leak-down test until the valves are checked and adjusted. - you KNOW they're leaking, so such a test wouldn't tell you anything.
Re: setting valve clearances
Posted: Thu Mar 14, 2013 2:54 am
by coops
DonTZ125 wrote:It's apparently rather common, if you're having hard start issues, for one or more intake valves to be too tight to measure. All you can do is swap in smaller shims and try to get a measurement. If you're lucky, it's in spec, otherwise you get to do the math and swap in another shim.
There's no point in doing a compression or leak-down test until the valves are checked and adjusted. - you KNOW they're leaking, so such a test wouldn't tell you anything.
True...But a compression test will tell me if i have a problem. (as long as there is some clearance there on a cold engine) Do i KNOW they are leaking?
How much clearance is needed? If they are leaking, they are knackered arent they? (burnt) But you are right, if theres no clearance, comp test is useless.
So il set the valves, do comp test, then pull it all appart again because i have two burnt valves
Im not that clued up on this 4-stroke buissness, im more of a 2-stroke man. But it is interesting. I do enjoy working on my bikes as much as riding them. Thanks for your help Don.
My new question
If there is no clearance when hot, this buggers the valve/seat?
Re: setting valve clearances
Posted: Thu Mar 14, 2013 4:10 am
by DonTZ125
An out-of-clearance valve isn't necessarily a burnt / ruined valve. The valve does pound itself into the cylinder head, and can distort the valve head. Running the engine with too-tight valves will indeed result in burnt valves, but there have been many happy outcome stories here and on the Archives, where a fellow had to take two and three tries to get a clean measurement as his valves were so out of spec, but was able to reuse the existing valves and seats without so much as a lap-in.
YMMV, every engine is different, using your powers for evil voids the warranty but is a lot more fun.
Re: setting valve clearances
Posted: Fri Mar 15, 2013 10:28 pm
by coops
So ive got the camshafts out and inspected the lobes of the two intake valves in question and one of the two is like the rest, unpolished (untouched) except for lobe area.
The other is just starting to polish all the way round. So im guessing i have about zero or slightly less clearance when hot on that valve. I will soon find out when i put the new pads in. ALL GOOD.
Bloody yamaha here charge like wounded bulls for there parts! They want $20NZD for each shim! thats about 16USD. I can get repops for about $5NZD each.
Same for yamaha clutch frictions and springs. For less money i can get Quality frictions and springs a rear wheel bearing kit a fork and dust seal kit and a clutch cover gasket. All quality stuff, delivered to my door, from USA.
Its the same with my kawasaki, I can buy OEM kawa parts from good old USA for about 70% of what i pay here for OEM parts. Thats including delivery, which can sometimes be hefty. Believe me, i know, ive spent nearly 30K collecting parts for my H1 in the last 3 years
Dont tell the misses
Re: setting valve clearances
Posted: Fri Mar 22, 2013 1:54 am
by coops
Well i got it right first time.(there was some clearance on the two tight valves) Thankfully cos what a cun tact getting the camshafts in at the right timing. I guessed too have the cams slightly advanced initially, so as they come down the chain slackens and they slightly retard into the right position. Glad i dont have to do it all again. Plenty of oppertunity to drop something down the camchain hole! I bet thats been done before. Then you would really have something to swear about.