Valve Timing

[evans]

Just replaced the head gasket on my z1000A1, but now bike wont start. Timing mark on the exhaust cam sprocket in manual shows a single mark which should correspond to a pin in the cam shaft. But mine has a mark either side of the sprocket which correspond to teeth on the sprocket. So these cams maybe replacements. Could it be that I have the exhaust can 180 degrees out ? Have good spark and fuel.

Cheers

Chris

[Pigford]

Chris.... if you've already been spinning the motor.....

Whip the plugs out and check for compression on all pots.....

If way out the valves will be bent (worst case) or no compression coz timings so far adrift

[evans]

Surely I would have heard a noise if valves were bent. No noise at all just wouldn't start ? I di make sure that nothing was going to touch etc by turning the engine slowly by hand before I put the rocker back on.

Chris

[Rich]

Have you put the advance retard cam lobe on the right way?

[evans]

Bike has been running great since I put the dyna coils and ignition on.
Not starting since I did the gasket etc. Definitley valve timing but surely I would have heard a crunch if something serious had happend ?

Chris

[Pigford]

If you turned over carefully by hand....... should have felt contact.
If kicked or electric start..... may not have noticed if only just touched.... but enuff to bend valves.... I know... been there, dun that, got the T-shirt & bill

That is worst case senario, so probably not that bad

Is there compression on all 4 cylinders

[chrisu]

do a search for the problems bigmac had when he did the same thing. not pretty.

[evans]

Definitely no contact when I turned it over by hand ?

[evans]

Pigford, what should the compression be, will go and test it now.

[chrisu]

could just be out then if you're lucky

have you checked against this diagram ?



I'd still want to do a compression test..........

[Pigford]

If you have a tester... cold.... a good +100 ....

If no tester, plugs out, thumb over each plughole whilst cranking... should POP your thumb off each comp stroke (alternate turns)

Good luck

[evans]

Compression very low, 1 - 30psi, 2 - 30psi, 3 - 0psi, 4 - 25psi.
In the diagram above where it shows the timing mark level with the top of the head on the exhaust cam sprocket, mine has a continuous line right across, so you don't know which way round it should be. The marks also match to a tooth rather than a pin in the cam chain. I know that I should have checked and marked the positions before removal, but assumed they were standard as in the diagram.

chris

[Pigford]

From memory, as you look at the end cam lobes, they are either both facing in or both out (on a horizontal plain)

That is low... but I'd expect 0 psi if valves bent, so may just be cams out.... or valves only just touched... still f**ked though if they did.

Need to establish true valve timing before weeping/praying/drinking...

[evans]

Pigford, cheers for the info, will take the cams out and review, suppose I can't tell if I have actually done anything to the valves unless I remove them. Suppose I can reset as you suggest, put back togther and see if it starts.

I can't believe you bent valves as you seem to know all about this sort of stuff.

thanks

Chris

PS Anyone replaced cams with ones with timing marks that sound like mine ?

[evans]

So does anyone know how to set up the valve timing in the absence of timing mark 4 as shown in the drawing above on the exhaust cam sprocket ?????
I understand that when 1&4 cylinders are at TDC (T mark) then this is the rocker position, from which point rotating engine forward cylinder 1 exhaust should start openening but rotating back cylinder 1 inlet should just start opening. How do I know when this point is and from where to count the 28 pins in the cam chain??

Any help much appreciated.

Thanks

Chris