Exhaust Valve clearance

[ Just learnt that this is wrong and RE sent out a wrong update. They put pictures and specs of the J engine in the Himalayan service manual...So ignore the post of mine]I just learnt something today. A customer with a Hitchcocks stage 2 cam was not happy with the valve noise and Hitchcocks sent them a RE update to the engine manual. Guess what, the exhaust valve clearance is 0.18mm now. I agree with the above discussion that the exhaust valve clearance is to loose. Guess what I'm doing tonight, adjust that exhaust to 0.18mm. Anyway here is the page out of the manual.
 

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a quote from @Sasa earlier in this thread.

"probably a more reasonable value would be like 0,18-0,20max, more in line with other bikes"

So eventually after the saga with frames cracking Magneto's frying, ECU's needing updates etc, we now have a Tappet clearance update.
How many more things go wrong with this machine :LOL:😆
And why wasnt all this sorted before release 😉
 
Dool said:
a quote from @Sasa earlier in this thread.

"probably a more reasonable value would be like 0,18-0,20max, more in line with other bikes"

So eventually after the saga with frames cracking Magneto's frying, ECU's needing updates etc, we now have a Tappet clearance update.
How many more things go wrong with this machine :LOL:😆
And why wasnt all this sorted before release 😉
Click to expand...
Check out my edit previous post. Wrong info was sent out by RE.
 
Curious that manual says to align at the T when all my tdc have been calculated at the line below the T. Wasn't this a discussion at some point too?
Kiwiscoot said:
[ Just learnt that this is wrong and RE sent out a wrong update. They put pictures and specs of the J engine in the Himalayan service manual...So ignore the post of mine]I just learnt something today. A customer with a Hitchcocks stage 2 cam was not happy with the valve noise and Hitchcocks sent them a RE update to the engine manual. Guess what, the exhaust valve clearance is 0.18mm now. I agree with the above discussion that the exhaust valve clearance is to loose. Guess what I'm doing tonight, adjust that exhaust to 0.18mm. Anyway here is the page out of the manual.
Click to expand...
 
The Line isTDC.
But for setting the Tappets T is close enough
 
Dool said:
Just over 1 turn for exhaust and just a bit more under a 1/2 turn for inlet?
Or 8 and 3 thou tight
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Explain it this noob please.🫣

If the thread pitch of tappets bolts are 0.75 then wouldn't 1 turn give 0.75mm gap for exhaust and 1/2 turn give 0.325mm gap for inlet??
 
Kiwiscoot said:
Explain it this noob please.🫣

If the thread pitch of tappets bolts are 0.75 then wouldn't 1 turn give 0.75mm gap for exhaust and 1/2 turn give 0.325mm gap for inlet??
Click to expand...
I blame it on the Decimal system, and the US's persistence in using a bastardized Imperial system :p
And not my inability to convert between the 2, I always use feeler gauges which have been freed from the holder and hang above my bench, last time I was able to read them it was 8 and a 4.(thou of course)
There is a lot of chatter about setting Tappets of late, its making more noise than the Tappets themselves.
I havent seen any burnt valves yet so they are not Too tight.
 
OK I keep from adding anymore chatter and 95% of the chatter will stop I guess.

Darn, now that I am quiet I can hear Himmas tappets again :oops: - off to do them the "turns" method.
 
Sbinf74 said:
Hi, looking at the valves of my motorbike I noticed that the exhaust stem, where the tappet works, has a convex surface facing upwards. I wonder how it is possible to adjust the valve clearance since we would be working on the edge with the feeler gauge.

I only have this photo but the problem is visible.
Has anyone who is more experienced ever noticed this?View attachment 1629View attachment 1630View attachment 1631
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I'm no expert, but doesn't the top of the valve look damaged and cracked and not the normal smooth edge? if so wouldn't small fragments of steel be floating around in the engine? And more could break away with the constant hammering of the tappet?
 
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