[Colchicine]

2007 Exec 24,000 miles / 38,624 kilometers

Imagine my surprise when I go to check my valve tappet clearances today for the first time and find that all 8 valves are either out of spec or at the very limits.

Tappet clearance:
Standard: IN..: 0.10 - 0.20 mm mine> 0.10 mm
EX.: 0.20 - 0.30 mm mine> 0.19 mm

In my time updating the BKB (hasn't been updated in ~3 years) the vast majority of people didn't need to adjust their valves. Those that did either had to do a few, or all of the intake, or all of the exhaust. Not all 8. So this has me concerned.

I have TheDarkCutlass (who has more experience with this) coming over tomorrow to double check behind me on this. So this will be updated if he finds something different.

I checked and rechecked I had all of the proper alignments. I even turned the crankshaft and checked all of the valves 2-3 times with various methods. What I did find was a large discrepancy between the two sets of new feeler gauges I had.
-First was an Autocraft from Advance Auto Parts. The smallest gauges was 0.102 mm and would not fit any ANY of the valves, even the exhaust side that I later measured to be a lot larger!
-Second, I went and bought a set, the brand was "OEM" from Pep Boys. The smallest was 0.04 mm and this is what I based my measurements on.

I have no idea why the 0.1 gauge on the Autocraft will not fit anywhere, but the 0.1 gauge from OEM will. I also have no idea why when I measured with the OEM gauge that I could fit a 0.10 and a 0.09 gauge together to get the 0.19 clearance on the exhausts, but when I tried using a 1.5 and a 0.04 together they did not fit.

Regardless, both feeler gauges show that all of the valves are too tight. This is baffling to me since the time when I was most active on here, I never encountered anyone with this problem.

My current plan is to get my measurements double checked, then I'll buy shims that will take the clearance up to the max spec.

 

[Buffalo]

Mine didn't need adjusting until I had 70,000 miles on them. However they were all at or close to the minimum just like yours.

 

[Colchicine]

Well, see, that's why I am second and third guessing myself on this. Why would yours last until 70K and mine all need work at 24K?

 

[DougInKY]

Is this your first valve check? If so, I guess I will follow the valve check intervals on this bike for sure. It has been my experience that I could skip the first valve check at 16,500 miles and wait until the second on most modern motorcycles.

Namaste'
Doug in Kentucky

 

[LeDude]

I did my first valve check at 54k miles and they were still within spec.

step back, double check your measurements and the way you are doing it, could just be
a miss read.

make sure everything is lined up correctly before taking the measurements:

good luck....

 

[Buffalo]

Well, see, that's why I am second and third guessing myself on this. Why would yours last until 70K and mine all need work at 24K?

Why do the bearings in one CVT fail at 30,000 and another go until the belt finally breaks and are still fine. Most of the folks with the late model 400s also report not having problems with the valves going out of spec but if I remember right Chris had to adjust his at 25,000 miles because they were out of spec.

 

[miken6mz]

On the 650 the valve clearance decreases with age/wear, is that correct?

 

[Buffalo]

Seems to be what most people report.

 

[Quantum Mechanic]

It is in fact quite normal. One in ten bikes needs the valves adjusting at the first valve check service, that's on average here in the Uk and will be roughly the same in the States. If the bike is being used in very hot climates or at altitude that also seems to affect the valve settings probably due to higher motor temps. How the bike is ridden, mostly high speed or mostly town work, also affects this aspect of servicing. But you guys probably know all that. It applies to most makes of bike and applies to the 400 and the 650. That's why valve service checks should not be missed by anyone. I carried out a 650 transmission strip for a new belt last year for a colleague, my first real encounter with the 650 oily bits. The bike also required a complete service. It had covered an actual 45k miles and all the valves needed reshimming as all were tight just beyond the lower limit. Got them just in time! Just shows how variable they can be.

 

[Dave_J]

I am at 48,000 miles and have never checked mine and do not plan to. Just me.

 

[dpilot]

I believe the valve stems get longer as they are "beat" upon, as they open and close valves under conditions of heat and speed. This would naturally make the clearances smaller
JimV

 

[Steve D UK]

I though it was because the valves hammer into the seats causing the valve clearance gap to reduce.

 

[Buffalo]

I would tend to agree with you Steve D. When I had the head off mine it was obvious the seats had receded.

 

[dpilot]

I think both things are true, but I have seen valve heads fall off and it was obvious that the stem had stretched, as the head end of it was tapered where the head used to be hooked on.
I also have seen seats with the part where the head touched receded.
I'm voting for either one or both.
JimV

 

[Colchicine]

Whew. Apparently I exuded pure newbiness the first time around checking the clearances. I've done a lot of things for the first time working on this bike, but this one took the cake.

It seems now that the Intake are all within spec,
0.17, 0.17, 0.17, 0.16.

Exhaust is okay, but one of them is still close to the limit
0.23, 0.23, 0.20-0.21, 0.23.

I put a range on that one because the 0.21 pretty tight.

I don't have a good explanation for how I bungled up mis-reading it before, but most likely due to two feeler gauges unknowingly stuck together.

Thanks to TheDarkCutlass for driving out to check it out.

 

[Buffalo]

Well now your not a newbie anymore so next time it will go better.

 

[Quantum Mechanic]

At least you realised something wasn't going right and were prepared to take advice. With that attitude you won't ever go wrong. Credit to the dark cutlass for helping out too.

 

[DougInKY]

At least you realised something wasn't going right and were prepared to take advice. With that attitude you won't ever go wrong. Credit to the dark cutlass for helping out too.

Yes, if you are trying something for the first time and you are getting wildly different findings than you were expecting, it is always a good idea to get someone who has done what you are attempting to look things over. Chances are that you are doing something wrong causing your findings. That second set of experienced eyes will help you avoid a possible expensive mistake. Good on you Cholchine for getting that help. You will never forget this and will never misgauge a set a valves again after this. Now, someday you might help someone else with this exact problem.

All ends well...
Doug in Kentucky

 

[Colchicine]

Thanks guys. Before this task I did not own a set of feeler gauges.

The reason for posting here before I had a definitive answer was because I wanted to be able to order the shims first thing Monday so they would be here before the weekend.

 

[LeDude]

Good job, its easy to get a bit turned around on the first valve check job on any bike, I know I triple checked myself the first time I ever did one, and still do to make sure that I have a consistent read.

A good set of metric gauges is a must. With a bit of patience and a methodical approach it can be a rather simple job.

You now a veteran valve checker, welcome to the club.

Glad to hear all is well.