Valve Shim change question...

[pinholenz]

Finally plucked up courage to adjust the shims on the XZ550 using the valve tool method.

The Haynes manual reckons that the engine should not be rotated without a shim sitting in the bucket. This of course is a right royal PITA. It turns an excruciating long job into a nightmarishly long weekend job. The best way to this would be

1. Measure existing gaps,
2. Take out all existing shims, noting the size installed in each valve.
3. Ccalculate shim size needed for new gap on each valve.
4. See what shim sizes you don't have for the job and source them.
4. Drop the correct shim size into each bucket.
6. Check new gap.
Good to go

Those of you have already done this job, my question is:

Will the cams REALLY do damage to the valve buckets if the engine is rotated by hand using the 14mm crankshaft bolt under the side cover?

[fret not]

NZ, I think you are making this more difficult than it needs to be.  The only way you can remove ALL the shims at one time is to rotate the crank so each bucket is under the base circle of it's lobe, remove those shims, then move to the others until they are all out.  Kind of a mess as I see it, and a significant opportunity to get things mixed up.  There is reason behind the method presented in the shop manuals, so I tend to follow that advice.

Hearty congratulations for getting the shim tool developed, you have done the Vision world a great favor.

[The Prophet of Doom]

What you need is a stash of spare shims so you can do it in one go.

[pinholenz]

Agreed. After getting the first shim out on the 550, I went and raided all the shims out of my 400 donor bike. That way I had a stock of shims to swap in and out. By the end of the day, I just need to source 2 x 250 shims and I'll be done. On Monday I will potter off to my local Yammy or Kawasaki workshop and see if I can do some swaps. All my valve clearances were about 0.05mm too tight.

The Mk3 shim tool (with the brass peened rivet) got a good workout. At one stage when I was thinking about food and not the job at hand, I got careless and managed to bend the shim removal tool. I didn't line it up properly and it got splayed open so that it was a sloppy fit on the cam shaft. I bent it back to the required 22mm across the faces in the vise, and it carried on working fine.

[Ken Williams]

If the cam lobe turns over a valve with no shim, the sharp edge of the bucket may come into contact with the outer edges of the cam lobe.  This may create a rough surface on the lobe where there is contact and perhaps break off some of the hard coat. 

[pinholenz]

Thanks Kim. I erred on the side of caution and never turned the  cam over without a shim in place.

Shims now sorted. It was a happy day.

I wandered into one of the local bike workshops today on the hunt for the two 250 valve shims. They must have had nearly 60 or 70 29mm shims all around the 270 mark. As I was leaving, I looked up at the bench and there was a XZ550 tank as large as life. There was another XZ in town! I have only ever seen one other XZ550 in the flesh in NZ. Sure enough it was in the workshop to try to have the carbs sorted. Turned out that it needed an accelerator pump diaphragm, which they couldn't source. Later on that afternoon I dropped in two sets of carbs that they could cannibalize for the clients pump.

As for my shims, I took a couple of oversize shims and had them ground to spec by a local engineering shop with all the gear. US$10 for them both. The ground face now sits at the bottom of the bucket with the untouched face against the cam lobe - just in case the hardening was affected.

[The Prophet of Doom]

I hope you left instructions on how to become a RoV Visionary.

[Rikugun]

This is a good post that illustrates the bad in shim/bucket valve trains.   :) Valve adjustments can be intimidating as it is. Add the need for special tools and a selection of shims and it becomes too difficult or impractical for some DIY'ers.

I'd agree with Ken in that I'd be more concerned with damaging the cam lobe in the scenario you described. That was a good idea to raid the other engine of it's shims. I'm fortunate to have a selection of shims but have had to go to a local shop and pay for an exchange. If I had to do that on a few valves, it would have been a very lengthy procedure. It may make sense at that point to measure the lash of all then remove the cams which of course adds another level of complexity. It's no wonder seemingly so few Visions have their valve lash checked regularly.

Very cool to randomly find an XZ at the shop. Also cool that you offered up spare parts. Did you use that leverage to barter for shims?

[vl5150]

I have the shim tool from pinholenz and it's indeed nice and I second the applause on getting it done.  After I finish my front brake project next week, I'll be doing the valve inspection as well.

Maybe I'll luck out and it will be OK. :o

As to my other bikes I've done this on, my Nighthawk 700 didn't need them as well as my Buell.  My ZRX had rocker arms that moved out of the way so 16 valves, but no tool required.  My CBR1000F has a cool 10MM nut and a allen key to set the lash and no shims (but 16 valves so still a pain).  The hardest was my Zephyr 750 with shim UNDER bucket.  I had to zip tie the cam to the timing chain to keep the timing intact and then unbolt the cams on both intake and exhaust.  What a pain that is!

So I'm looking forward to only 8 valves, lol.

[Rikugun]

For clarification the Nighthawk uses hydraulic adjusters under the follower and I guess the Sportster uses hydraulic lifters as HD was fond of using that method in later years. I often wish more all bikes used a similar method.

I worked at a Kawasaki dealer in the early 80's and the 550/650/750 engines were widely used and very popular. Removing cams and setting valve timing became "old hat" but never fun.  :(  Relatively speaking, the Vision isn't so bad.