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Discussion Starter #1 (Edited)
I measured my valve clearance at 600 miles and it was close enough to spec to leave it. Intake were dead on at .007, .007 inches. Exhaust was at the tight limit of the spec at .010, .009. I checked them again at 3,800 miles and found that all four valves needed adjustment. The intakes had tightened up to .005 and .006 inches and the exhausts were .007 and .008. Time for some shims. Measuring the valve clearance is easy. Anyone can do it at home. Three bolts and the side fairings pop right off. One bolt and the radiator can hang down enough to sneak the valve cover out the front. Remove the spark plug so you can bump the engine into the correct timing positions for each cam with the lobes straight up, away from the roller. Measure with feeler gauges. Easy. Changing the shims is much more risky and will be better left to a bike shop unless you have a full selection of professional tools and are very good with them. The amount of time it will take you might be better used to pay the bike mechanic who does this sort of thing all day long and has all of the parts handy with out driving back and forth. You can always measure again when you get home to check his work. If you do try it yourself, it might be worth it to pull the tank and move the wiring and splash shields so you can reach right down from the top. I snuck mine in with the tank in place but ended up using a bore scope to see what I was doing for the exhaust shims and probably wasted more time trying to be careful. At least I didn't drop them down the engine which would be pretty easy to do. I changed each shim to the next thinner one and ended up with the intakes at .009, and .008 inches and the exhausts at .009 and .011 after bumping the engine around ten times to make sure everything was seated. The left exhaust didn't change as much as I had calculated it would. Don't know why. Maybe there was a piece of dirt under it and it will run in. I wanted to take them all to the loose end of the tolerance so I wouldn't have to do it again for quite a while but now I will have to recheck them again in a few thousand miles.
 

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Cool thanks for the info..
Ive a hunch~
I might stretch my 1000 Km first service out to 1250 or so next week... and wring its neck from 1000-1250km.. might just be better to settle them? (since yours did seem to change a bit more after 1000km)

Or would this not make a difference?
 

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I'm in exactly the same boat Sendler. I did my valve check at 1500km and they all were in spec, but the exhausts were close. I decided to leave them and check them after I put it away for the season (approaching very fast sadly).

My plan is adjust them on the loose side to allow as much time between adjustments as possible.

I've got a little over 3K on the bike now and expect to be riding for at least a few more weeks (supposed to be low 70's this weekend!). Probably mid November.
 

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Good question Aufitt.
A shop I talked to said that the chance of needing the valves adjusted depended on how aggressively the bike was ridden for the first 600 miles. That would lead me to wonder - since it will be many miles before the valves get checked again, wouldn't you want them to move as much as possible before your first service?
 

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Discussion Starter #5
checking is easy

Cool thanks for the info..
Ive a hunch~
I might stretch my 1000 Km first service out to 1250 or so next week... and wring its neck from 1000-1250km.. might just be better to settle them? (since yours did seem to change a bit more after 1000km)

Or would this not make a difference?
Checking the valve clearance is easy. I wouldn't put it off. If it is close enough you can then leave the actual adjustment until later. If the valves get too tight it will cause premature wear so it is good to know where they are and then decide.
 

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like pete I just didnt want to do it twice before the 24,000km one 2 yrs away.

And the 1000km first service has to be done anyway... that bit more settling in might make it worth it. the way mines clocking up the K's it will be well over anyway by Tuesday week.
 

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Discussion Starter #7
Warranty

like pete I just didnt want to do it twice before the 24,000km one 2 yrs away.

And the 1000km first service has to be done anyway... that bit more settling in might make it worth it. the way mines clocking up the K's it will be well over anyway by Tuesday week.
Don't go to far past the mileage with out at least having it measured. If you skip the first service and something happens, Honda can void your warranty.
 

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Much respect for doing the job that scared me away.

How did you manage to position the shims when installing them ?
With some long curved forcept type instrument ?

I couldn't see myself doing the job with the tank lifted (not removed), let alone with the tank in place !
 

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When I did mine (and the exhaust's did need new sizes) the most important tool for me was a magnet probe to get the shims out...easy enough. I then used some crappy old computer repair tweezers to place the new shims 'close enough' to the collet area..then used my finger to position it home. But a cpl of times slipped out...thats when the magnet probe was of real value. :eek:. In the end got them in OK.
I did it as others have done laying the radiator down and coming in from the front of the engine, but reckon Sendler's tip to remove the tank and work from the top is safer (for no shim loss that is).

As I have ranted before, it's BS that so many dealers don't reckon they need to check em in the first service. It's way too long for the next check..24000 km!!! no way. I will check mine again in say 5000 km. As the guys say, the check is very easy to do.
 

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Discussion Starter #10
Magnet

Much respect for doing the job that scared me away.

How did you manage to position the shims when installing them ?
With some long curved forcept type instrument ?

I couldn't see myself doing the job with the tank lifted (not removed), let alone with the tank in place !
I could have taken more photos but at that point, I just wanted to get out of it alive. The mess of assorted tools laying all in a pile would have told the story well when I was done but it was late and I still had to ride 40 miles home.
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I used a magnet on a stick to grip them on the edge to get them into position and then poked them home with a pick that you see in the screen shot I posted from the bore scope. The last thing I wanted was to drop one. I don't know if there are any oil return bores big enough to swallow a shim but I didn't want to find out as I would have been walking. I did stuff the spark plug hole shut with a paper towel. The hardest thing is that you can't see the tops of the exhaust valves so I was lucky I have a scope. Otherwise you will be relying on your imagination and sense of feel.
 

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...
I used a magnet on a stick to grip them on the edge to get them into position and then poked them home with a pick that you see in the screen shot I posted from the bore scope. The last thing I wanted was to drop one. I don't know if there are any oil return bores big enough to swallow a shim but I didn't want to find out as I would have been walking. I did stuff the spark plug hole shut with a paper towel. The hardest thing is that you can't see the tops of the exhaust valves so I was lucky I have a scope. Otherwise you will be relying on your imagination and sense of feel.
Thanks for the word.

I relied on a handheld mirror on an extendable stick so that I could see where to stick the feeler gauges to measure the exhaust clearances. I could not imagine, with the tools that I had, how in the world was I going to be able to get a replacement shim in there.
I've since gotten some fancy curved artery forceps from a surgical supply distributer (this is what my mechanic showed me that he uses in conjunction with the magnetic pickup).
Some kind of scope or mirror that doesn't have to be held onto, such as what you have, sounds like the last piece of equipment that I'd need.
 

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Discussion Starter #12
Tweezers and mirror

some fancy curved artery forceps
.
Some kind of scope or mirror that doesn't have to be held onto, such as what you have, sounds like the last piece of equipment that I'd need.
The magnet was hard to deal with on installation. Something like the spring closing electronics picking tweezers I have would work great If I can somehow mold the right shape on the end to hold the curve of the shim. Now I am wondering if there may actually be a special tool for this purpose.
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The scopes are too expensive to buy just for that but you may find a mirror with a goose neck flexible shaft mounted to a magnet that could stick to the tank or the frame and be bent into position.
 

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Don't go to far past the mileage with out at least having it measured. If you skip the first service and something happens, Honda can void your warranty.
No I'm not skipping it thats for sure.. maybe I didnt write it properly.
Just an extra 10-20% mileage to settle it in and make the valve adjustment worthwhile... since you did say it had changed since the first service.
 

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Got my bike back today fom getting the valve clearances done at 1188km ,
dropped off Monday night so cold this morning. (tues)

heres what they said-

'Inlet 5-6/ allowed 5-7'
'Exhaust 10-11/ allowed 10-12'

This bike was heated/cooled carefully and taken to 5000rpm first 100km
6000rpm first 200km
7500 rpm till 500km
then progressively taken to redline & 157 kph till 1000km,
then the past 200 km absolutely worked as hard as a cbr needs to (ie flatout all the time) to be a half decent open road ride and tops out at 163kph.

No rattles ever.
Never free revved without load, and not laboured either.
Still a bit tight feeling but that will improve.

I know the debate is always there and its a personal choice... but Ive proven to myself that running an engine in is they key to a happy motor... the way Honda set the clearances seems spot on.
 

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AuFitt, Have you checked your speedo vs GPS? Mine is indicating 10% high.
All speedos are.. you should see Kawasakis in general lol.. Mate claiming 299kph on his big kwacka and my Trumpy passes it at 268 kph flatout.
'Kawasaki kph' its been refered to for years haha.
(And 'Kawasaki kilograms' vs Triumph/Ducati kilograms. put em on bathroom scales you'll see.)

All of our (stock gearing) kph bikes will be the same worldwide, True gps speed wont make a difference for me to check performance improvements I do in the future as a baseline.
(if that makes sense)

My boat has a GPS.. now that is accurate as its at sea level and flat... she only does 64kph GPS but shows 70 on the speedo.. and against the current only does 61 but shows 75 on the speedo. but its a 90hp Honda pushing 1100kg.

*ps ...if you want to break the ton.. put 34 psi in the rear tyre and 32 in the front... less resistance and make yourself a contortionist.
Here we go off topic again hehe.
 
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