Right ive just done the clearances on my 1991 red/black NC30 with 71K on the clock.
these are the results
Valve clearances!!
All checked and all just within the tolerances.
cylinder 1 inlets 0.12 and 0.13 outlets 0.23 and 0.21
cylinder 3 inlets 0.12 and 0.13 outlets 0.23 and .021
cylinder 2 inlets 0.13 and 0.13 outlets 0.23 and 0.23
cylinder 4 inlets 0.13 and 0.13 outlets 0.23 and 0.23
All fairly close but thought I would leave alone, your thoughts??
Ta
Kris
Valve clearances second opinion
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- ibby4585
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Re: Valve clearances second opinion
be different kris and change them like 10mm each way and have an engine sound like you have a bag of spanners!
the CBR125R i have, has a recomened gap of inlet 0.06mm and outlet 0.27mm
inlet is about 7mm and outlet is 0.35mm ish
no wonder it ran like and sounded like a dog, ill get this tuned up when my new tappets arrive
and plenty of other DS Spares
the CBR125R i have, has a recomened gap of inlet 0.06mm and outlet 0.27mm
inlet is about 7mm and outlet is 0.35mm ish
no wonder it ran like and sounded like a dog, ill get this tuned up when my new tappets arrive

and plenty of other DS Spares
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- micpec
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Re: Valve clearances second opinion
Kris, there is nothing wrong with those measurements. You can just leave it as is albeit a bit on the "tight" side.
(I rather focus on the middle of both min/max areas...inlet 0.15 and outlet 0.24...while the engine is opened for measurements I thought I might as well adjust it).
(I rather focus on the middle of both min/max areas...inlet 0.15 and outlet 0.24...while the engine is opened for measurements I thought I might as well adjust it).
"Action without Philosophy is a lethal weapon; Philosophy without action is worthless"
- ibby4585
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Re: Valve clearances second opinion
Cheers Jas. If I was keeping it I would loosen them a bit! But it's getting sold so trying to keep the costs down!
It's amazing how everything adds up! I don't want to make a massive profit on it just enough to cover my costs!!
Kris
It's amazing how everything adds up! I don't want to make a massive profit on it just enough to cover my costs!!
Kris
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Re: Valve clearances second opinion
If you are getting rid, then leave them. Personally I go for slightly larger than the middle range of tolerances but that is just me..
If they are in spec then the bike is a doozy..all good. I doubt anyone off here would have any issues buying it after all the effort you have put in.
Saying that...I want to see the biggest HRC blag HRC blag advert going and see if you can convince anyone that it is a one off, owned by the Emperor of Japan etc...
If they are in spec then the bike is a doozy..all good. I doubt anyone off here would have any issues buying it after all the effort you have put in.
Saying that...I want to see the biggest HRC blag HRC blag advert going and see if you can convince anyone that it is a one off, owned by the Emperor of Japan etc...

IMPERATOR REX ANGLORUM
The V4 is the law..
NC30 - No9 - my old mate
The V4 is the law..
NC30 - No9 - my old mate
- ibby4585
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Re: Valve clearances second opinion
Mark there will be HRC galore in the Ad! I'm hoping for 5grand!!
Kris

Kris