Valve clearances - K3.

[Sid Squid]

It's easier on a 1000 as the final drive to the cams is by gear, so you don't need to disturb the cam chain and tensioner, and re-timing is dead easy.

With all SV models, crack the turning plug when the engine is hot, if it won't move or starts to distort, get a suitable socket, 30ish mm, and give the plug a few sharp taps around it's edge, and also few similar taps around the hex, but not in it - it's very thin at the back. When you refit it, use some anti seize on the bit outside the 'O' ring that touches the case, which is where it corrodes and sticks. If your tool isn't a very good fit in the socket, (fnaar), use a rag or similar and put if over the hole and gently tap the tool into place - often helps if the socket has been distorted by a previous removal attempt. If it still won't come out cold chisel it round very carefully, and buy a new one - about a tenner as I recall.

Thanks for all the replies everyone. I checked 3 times to make sure I had it all in the right place...

The buckets weren't touching the cams, just that the gap was smaller than my smallest feeler. (0.05mm) I just thought it was a bit odd that all four on one cylinder were out... Nothing was obviously wrong when it was running. Always started first time etc. Just fancied checking them myself this time and that's what I found. I have ordered the appropriate shims. When they arrive, hopefully before Xmas I'll put them in and measure again.

Thanks again for your replies.

Originally Posted by k1ngy SV

does 5k miles really make that much of a big difference? & my bikes fine on fuel and no silly noises coming from engine area... just the exhaust

The problem is that they make noise when they're loose, but not when they're tight. Tight clearances can burn valves. Valves get a significant portion of their cooling from the time that they are pressing on the seat. Tight valves sit less on the seat, ergo less cooling.

[Sid Squid]

Originally Posted by bellisan

Tight clearances can burn valves. Valves get a significant portion of their cooling from the time that they are pressing on the seat. Tight valves sit less on the seat, ergo less cooling.

The man speaks sense - listen to this.

Also, some reasons:

Originally Posted by Me, a long time ago

Every time the inlet valve opens it receives a nice cooling rush of incoming gas, and when it's closed it dissipates heat through the valve seat, even though that's a small area for conducting away heat - every little helps - in short the valve itself has an easy life, and thus wear in the opening mechanism commonly outweighs the wear to the valve - thus the clearance often opens up a bit. Exhaust valves however don't have such an easy time, they get and stay very very hot, their primary way to dissapate heat is the thin ring of the valve seat, and a little up the stem, everytime the long suffering exhaust valve opens it gets fried with gas at/near combustion temperature - typically 300-700C - thus in the case of the exhaust, the valve tends to wear more than the opening mechanism, hence the clearance reducing.

Also we have a nasty Catch 22 - if the clearance becomes significantly reduced, (or worse still if there's no clearance and the valve never fully closes), the valve spends less of the already small amount of time that it should do closed, thus it never dissipates the heat it should do and can literally melt, this is called burning a valve, no surprise there, and you really don't want to get into that.

A round of applause for your exhaust valves please - the hardest working bit of your bike, full stop.

Update:

Shims arrived yesterday, so after swapping around and re fitting etc they are all now within spec.

Anyone wanting to check / adjust. It's not half as difficult as you might think. Although I did find the Suzuki manual described the process better than the Haynes equivalent.

Thanks to everyone for your input.

[Mark_h]

Originally Posted by Sid Squid

It's easier on a 1000 as the final drive to the cams is by gear, so you don't need to disturb the cam chain and tensioner, and re-timing is dead easy.

With all SV models, crack the turning plug when the engine is hot, if it won't move or starts to distort, get a suitable socket, 30ish mm, and give the plug a few sharp taps around it's edge, and also few similar taps around the hex, but not in it - it's very thin at the back. When you refit it, use some anti seize on the bit outside the 'O' ring that touches the case, which is where it corrodes and sticks. If your tool isn't a very good fit in the socket, (fnaar), use a rag or similar and put if over the hole and gently tap the tool into place - often helps if the socket has been distorted by a previous removal attempt. If it still won't come out cold chisel it round very carefully, and buy a new one - about a tenner as I recall.

I fear we're into yet another of my seized to buggary fixings. The engine turning cover widget is stuck. In the "good ol' days" when working on cars you just used to spin the engine over on the starter to get to the timing points. Is this do-able on the bike or am I better

a) stick it in gear and spin the back wheel to get aligned
b) take the front sprocket cover off and turn it there
c) persevere with the engine turning cover widget as per above
d) work on the assumption all is fine, change the oil, pump up the tyres and just ride it until is rattles or smokes more than usual?

[jambo]

Mark, I'd go with Option 1.

If you actually need to change any shims, you may need to make sure you can see any timing marks at the crank, but just to check them you can just make sure the lobes are facing 180 degrees from the buckets on the cam you're checking at the time.

Jambo

[yorkie_chris]

Originally Posted by Mark_h

I fear we're into yet another of my seized to buggary fixings. The engine turning cover widget is stuck. In the "good ol' days" when working on cars you just used to spin the engine over on the starter to get to the timing points. Is this do-able on the bike or am I better

a) stick it in gear and spin the back wheel to get aligned
b) take the front sprocket cover off and turn it there
c) persevere with the engine turning cover widget as per above
d) work on the assumption all is fine, change the oil, pump up the tyres and just ride it until is rattles or smokes more than usual?

Un stick it.