Valve check on a 4th gen -- what do I need?

About to hit 19K on my 4th gen and she's not running as smoothly as she used to so I figure it's time to give those valves a peak and sync the carbs.

For the valve check, I want to get new valve cover gaskets as well as silicone sealant. I don't want to have to rely on reusing the 16-year-old originals.

What other things are likely to need to be replaced while I'm in there? I was also thinking the fuel filter. Already did my air filter about 3K back.

It might only need a good carb cleaning, the valves are known to be really solid and not move around much at all.
The fuel filter is super easy since it's in line with the fuel pump and not in the tank, a good $11 at Autozone will be more than enough, not really sure if there's much else to do besides the regular oil and chain cleaning...

Although the 4th gen is known to hold it's valve celarances well over the 16K valve maintenance interval, 19K might be starting to get up there, It wouldn't hurt to do an inspection IMO.

Beck
95 VFR.

[image: View Post]mrmatt, on 01 February 2011 - 05:09 PM, said:

It might only need a good carb cleaning, the valves are known to be really solid and not move around much at all.
The fuel filter is super easy since it's in line with the fuel pump and not in the tank, a good $11 at Autozone will be more than enough, not really sure if there's much else to do besides the regular oil and chain cleaning...

Inspecting and adjusting the steering head bearings would be good to do if that had not been done yet since new. Same with balancing the carbs for smoother running.

Beck
95 VFR

Aren't spark plugs due every 8k mi? You'll be right in the area. When I checked my valves (all within spec @ 32k mi) I also removed the radiator and gave it a good flush.

Beyond that, it's good time to do some cleaning.

I bought my 4th gen with 31,000 and immediately took it to a Honda guru that I know. The valves were fine. He cleaned and tweaked
the carbs. I replaced the fuel and air filters. The bike woke up after the fuel and air issues were taken care of. At 40k +, it's still
running fine.

All you would need to check the valves would be a feeler gauge & patience.... as for the valve cover gaskets I would not worry about them being old as the valve cover is grooved like tuperware. As others said I think if you synched your carbs along with new plugs she will be back to running fine :fing02: I checked my valves @ 50k and all was in spec. She now has 75k and is still running like a top :cheerleader: Good Luck!

Gary

If you do check the valves, do post up here :fing02:

Not bothered so far (60,000kms).
Did have the headbearings replaced (that was an improvement!) and the carbs synced.
The mechanic told me that the carbs were still ok'ish and only needed minor adjusting to make them perfect in line again.


YMMV

Spark plugs! How could I forget that one.

What plugs should I use?

[image: View Post]Dutchy, on 02 February 2011 - 08:11 AM, said:

If you do check the valves, do post up here :fing02:

Not bothered so far (60,000kms).


I did mine recently and posted this on a UK forum





One of the big service items on VFRs is the valve clearances. They are due every 16000 miles but they are often ignored because they're a pain to get to, and they tend to close up so they don't rattle. As I have the bike in pieces it makes sense to check them. The rear bank of cylinders are easily accessible, the cam cover is held on with just four bolts.

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The front cylinders are a bit more awkward, so I removed the radiator to improve access

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Check each valve and make a note of the gap - inlets should be 0.16mm and exhausts 0.25mm, +/- 0.03. All the exhaust valves were ok, but five of the inlets were too tight, ranging from 0.10 to 0.12.

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The next step is to remove the cams so that you can check the size of the shims. The VFR's gear driven cams make this easy, just undo the camshaft cap bolts and they lift out.

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Use a magnet to remove the bucket, and the shim is underneath.

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Although the shims are stamped with their size, it's a good idea to measure them with a micrometer as some of mine were a bit worn and thinner than they used to be - the result of 52000 miles of use.

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Once you know the actual gap and the shim size you can work out what shims you need to get the gaps back within spec. I managed to shuffle some shims around to get three of the five gaps correct,

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I had to order two new shims at �2 each from David Silver (I ordered a few other bits and pieces to make up a reasonable order)

With the new shims in place I could replace the cleaned up cam covers, job done for another 16k

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I used the attached Excel file to work out what shims I needed. Apologies to our US readers but it's in metric rather than Imperial.

[image: Attached File]  shim.xls (21K)
Number of downloads: 16

Thanks for the write-up Druid!!! :fing02:

Yes thank you!

Stupid question: Can you stack shims to build the thickness you need or do you have to use a single shim at the correct thickness?

[image: View Post]VFR72525, on 06 February 2011 - 12:43 PM, said:

Yes thank you!

Stupid question: Can you stack shims to build the thickness you need or do you have to use a single shim at the correct thickness?


No shim stacking