Valve Clearance Guide

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sabdyz@hotmail.com
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Re: Valve Clearance Guide

Post by sabdyz@hotmail.com »

hi im goin to doin ma clearances soon and just had a q...
the valve clearance is the total space between the top of the valve spring to the bottom of the rocker arm? is that right? and the shim is added to make that space fall in the tolerance range?
so if i remove the shims measure the gap (using feelers) then deduct say 0.15mm from the measurement i got that will give me the size for the shim needed for the inlet valve for my NC30??
thanks
code2006
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Valve Clearance Guide

Post by code2006 »

sabdyz@hotmail.com wrote:hi im goin to doin ma clearances soon and just had a q...
the valve clearance is the total space between the top of the valve spring to the bottom of the rocker arm? is that right? and the shim is added to make that space fall in the tolerance range?
so if i remove the shims measure the gap (using feelers) then deduct say 0.15mm from the measurement i got that will give me the size for the shim needed for the inlet valve for my NC30??
thanks
The way I done it is I measured the gap then took the shim out and measured that. It will make life easier later on when u want to start swapping shims around
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CMSMJ1
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Re: Valve Clearance Guide

Post by CMSMJ1 »

sabdyz@hotmail.com wrote:hi im goin to doin ma clearances soon and just had a q...
the valve clearance is the total space between the top of the valve spring to the bottom of the rocker arm? is that right? and the shim is added to make that space fall in the tolerance range?
so if i remove the shims measure the gap (using feelers) then deduct say 0.15mm from the measurement i got that will give me the size for the shim needed for the inlet valve for my NC30??
thanks

The clearance is the gap between the shim and the rocker arm finger - measure it. then take the shim out and measure that - then do the maths
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shanet675
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Re: Valve Clearance Guide

Post by shanet675 »

I know this is a old posting but i'm currently doing my 90mod NC30 I live in Australia and I been to a Honda dealership to get some shims they exchanged me ones that they use on CRF250's which come in at 7.48mm OD my vfr ones are about .04mm bigger is it all right to use the crf ones? I have put them in but they don't seem to be seated as good as the others, I've got the lashing right but I don't want to ruin the valve seats.

Cheers

Shane
phongus
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Re: Valve Clearance Guide

Post by phongus »

Hi.

I was going to attempt to do this myself today but I am having some issues getting the timing cover cap off which gives you access to the timing nut to set it to T1/T2.

I originally used a 12 pointed 17mm socket to get the cover off...thinking the cover wasn't on too tight but ended up rounding the nut slightly. Not going to attempt a second time I went out and bought myself a 6 sided impact socket which fit snuggly into the cover nut. Using a T-bar and the impact socket...I still couldn't get it off :| .

I then decided to add a 1 meter pole to the T-bar to get more leverage, but the cover still wouldn't budge.

This may be a stupid question, but is it a twisted on cover with normal thread? Because it is pretty stuck on fast :?
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CMSMJ1
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Re: Valve Clearance Guide

Post by CMSMJ1 »

It should be a normal thread and is usually not too tight.

If youa re worried about breaking it off then you can whip your plugs out and turn the bike over using the back wheel in gear..
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phongus
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Re: Valve Clearance Guide

Post by phongus »

CMSMJ1 wrote:It should be a normal thread and is usually not too tight.

If youa re worried about breaking it off then you can whip your plugs out and turn the bike over using the back wheel in gear..
Thanks CMSMJ1.

If I was to do it that way, do I use the plug holes to note if the cylinder is at TDC or not (piston at the top or bottom)? I assume that the markings on the camshaft can be 180 degrees off...so if the marking on the cam is pointing down...it can be either at TDC or BDC?

Just want to clarify before I do something really stupid.
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CMSMJ1
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Re: Valve Clearance Guide

Post by CMSMJ1 »

I reckon you can work out, fairly easily where you are in the sequence byt checking the little camshaft marks against a look in the spark plug hole and see if the piston is there.

You can then work the sequence out as the cams turn over teice per crankshaft so you can use them as your reference.

As long as the cams are not acting on the fingers you can slide them across to get the shims out and see their sizes too.

Hope this helps :grin:
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phongus
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Re: Valve Clearance Guide

Post by phongus »

CMSMJ1 wrote:I reckon you can work out, fairly easily where you are in the sequence byt checking the little camshaft marks against a look in the spark plug hole and see if the piston is there.

You can then work the sequence out as the cams turn over teice per crankshaft so you can use them as your reference.

As long as the cams are not acting on the fingers you can slide them across to get the shims out and see their sizes too.

Hope this helps :grin:
Sweet...thank you for your help. Had to read it twice because "teice" didn't make sense the first time :D.

Cheers
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CMSMJ1
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Re: Valve Clearance Guide

Post by CMSMJ1 »

lol..yes,my typing skills are bobbins.. I can spell, just not type!

twice it is then ;)
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The V4 is the law..

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