What are these holes?
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- NGneer
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What are these holes?
Ok (hopefully) a simple question - but what are these holes for on an NC30 engine, under the starter motor / oil filter (marked by white arrows)?

Before you ask - I don't have access to my Haynes and various other manuals to check the official documentation, and am a bit rusty as I have been off the spanners for a couple of years. It was just niggling me that I don't know

Before you ask - I don't have access to my Haynes and various other manuals to check the official documentation, and am a bit rusty as I have been off the spanners for a couple of years. It was just niggling me that I don't know

- thunderace
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Re: What are these holes?
Oil cooler ports for a UK spec engine 

Conventional wisdom says to know your limits. To know your limits you need to find them first. Finding your limits generally involves getting in over your head and hoping you live long enough to benefit from the experience. That's the fun part.
- alexwitham
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Re: What are these holes?
I don't know for sure, but I would imagine they would be for the fitting of an oil cooler such as the one on a UK spec bike.
That'd be my guess anyway
That'd be my guess anyway

- NGneer
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Re: What are these holes?
thunderace wrote:Oil cooler ports for a UK spec engine
That was my initial thought - but i dont think so as these are on what (I believe - and have no reason to doubt) is a Jap spec engine, plus any pictures I have found on line of an NC30 engine from this angle - all have the same sort of ports

- Drunkn Munky
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Re: What are these holes?
UK spec oil cooler, 100%. Why the earlier jap spec motors had the ports but no cooler ive no idea, more honda wisdom i guess.
- NGneer
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Re: What are these holes?
Drunkn Munky wrote:UK spec oil cooler, 100%. Why the earlier jap spec motors had the ports but no cooler ive no idea, more honda wisdom i guess.
Ahhhh -

So am I correct in taking that as ALL NC30s will have these 'ports' on the casings but only the UK spec motors will actually be 'functioning' (ie tapped through the casing and into the oil system).
- speedy231278
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Re: What are these holes?
I'm pretty sure the NC35 has them too. I guess Honda decided it was easier and cheaper to make one casting that fits all, and just machine the necessary threads into the ones that were destined for bikes with the oil rad. The advantage of the rad over using the one that fits behind the oil filter and uses engine coolant is that the latter means you need to lost the rad fan for it to fit... Or at least, that's how I understand it.

- mruehl34
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- speedy231278
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Re: What are these holes?
Perhaps saying the export models had it would be more accurate, although in the past I'm sure everyone has referred to it as the UK spec...

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Re: What are these holes?
The nc30 motor has the same engine casings as the nc24,the nc24 was fitted with the oil cooler,
When they first built the nc30 it was for the japanese market only,The same casings were used,But They were left blank,Not drilled, When introduced to the UK they were fitted with the cooler.And up-graded pump (NC24).
I have drilled and taped threads in the jap casings to take the cooler tis easy.
When they first built the nc30 it was for the japanese market only,The same casings were used,But They were left blank,Not drilled, When introduced to the UK they were fitted with the cooler.And up-graded pump (NC24).
I have drilled and taped threads in the jap casings to take the cooler tis easy.