Questions on valve adjustment VF1000R

So I check my valve clearances and find they are around .28mm when the recommended clearance is .14 mm give or take .02 mm. No noticeable noise but will take them back to spec…
What I have noticed is that when I come to torque the nut down, the socket I have will not fit correctly on the nut head because of the angle of the rocker arm when the valves are closed. I am setting the other cam lobe on the same shaft to fully open when the top of the lobe has depressed the rocker arm fully.
Is it possible to tighten the nuts with a spanner pretty tight then rotate the cams until they are in a position to be torqued to spec? Leave the feeler gauges in?
all comments and tips appreciated.

One recommended trick is to tighten with spanner (feeler in place, then remove feeler) then turn crank until tappet is about half depressed on the cam. There should be room at that point to tighten to torque spec. then rotate and check clearance again. Thats what I do but there are some real experten on here!

That’s as good a way as any Drew

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Yep pretty much did it that way. Had to fiddle with the gaps more than I thought to get them right.
Torque spec is 21 -25 nm - wow that seems very high for such a small nut. Actually one nut did strip.When I undid the nuts they didn’t seem that tight.

Hi,
one good way to adjust your valves:

Find the right setting on the cam to adjust valves (top dead center). Loose the nut and screw so they are free. In stead of using feeler gauge under the two srews, for each valves, you put the gauge between the rocker arm and the cam. The clearence should be .10 mm. Then just finger tight carefully both the screw so they touch the valve with the .10 mm gauge between the cam and rocker arm. Then finger tight the nut. Take away the gauge. Turn the engine until the lobe are pressing the valve down. (Halfway or full dosen’t matter, the screw wont’t change position). Then you can tight the nut with a socket. You wil find that the clearance is now .15 mm on both valves when you turn the engine to top dead center again. And the good thing here is that they have exactly the same clearence. Beacuse there is often a bit slack in the rocker arm, so when you set the first valve, and then the second valve, very often there will be different clearance on the two valves. Good luck!

Very interesting method. I agree that with the Honda method I have found it very difficult to get both clearances on one rocker arm the same. Your method would ensure that both gaps are the same.
Have you ever found the cam to rocker arm gap differs from .10 mm due to manufacturing differences? If there are variances from cam to cam and bike to bike then the Honda method would ensure gaps are within spec?
Has anyone one else used this method?

I tend to use the 2 feelers gauge method as per manual, but I’ve never used a torque wrench, just go for a good tighten with the spanner…

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Hi again, no never found any difference from cam to cam. After the adjustments, you should check the valve clearance. (For this, use two gauges) I bet it’s correct :slight_smile: I found this method explained by a race mechanic in US with a lot of experience on Honda V4 machines. It’s a hassle to operate two gauges at the same time. There was a special tool from Honda to take out the slack in the rocker arm, but it was withdrawn again, a lot of adjustments turned out to be too tight. I guarantee you, this is a perfect way to both get the right adjustments on clearance and both valves equaled. Give it a shot and you will never do it differently in the future :slight_smile:

At work we have stainless steel metal sheets of various thickness. I cut two stripes of 0.12 mm and use them between screw and valve on one rocker arm.

I thought about doing it this way but wasn’t sure about the ratio and as I hadn’t seen it mentioned before so stayed with the two feeler gauge method.
Next time, which hopefully will be not for a while.

I’ve just tried kjetil’s method of the feeler between the cam and rocker and seems a good idea. Thoughts on clearance, mines a 84 vf1000f, manual says .12 clearance is this a bit tight , should I go .15 on valves? Or is this for the R’s only,Thanks in advance

0.15 mm should be fine should you have a fraction of valve seat recession. The variance can be +/- 0.02.
I have found that new bikes and rebuilt valvetrains can have initial reduction in clearances when bedding in but after a check at a few thousand kms the clearances are usually spot on for ages after that.

Yeah thanks, I’ve done just under 2k since total rebuild so I was just going to give him a bit of a check over