Ideal valve clearance

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Drunkn Munky
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Ideal valve clearance

Post by Drunkn Munky »

So what would be the ideal valve clearance settings? manual states,

Inlet 0.12 to 0.18
Exhaust 0.21 to 0.28

The spec sheet for a tony scott motor states

Inlet 0.18
Exhaust 0.28

Theres no give or take with the tony scott settings and there both at the top end of the haynes manual settings so does that mean ideally you want them set to this? This isnt for the t scott motor by the way, just a stock motor used for track.
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Re: Ideal valve clearance

Post by RSVR »

DM,
If it a stock motor I would plump to the middle of the road for both inlet and exhaust.
Then dependant on how hard you rag, :twisted: I mean ride it , will allow for creep either way you’ll still within specified tolerance.

The TS motor, I assume the heads have been skimmed and are they standard cams?

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Re: Ideal valve clearance

Post by Drunkn Munky »

HRC cams in the TS motor
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Re: Ideal valve clearance

Post by Variablevalves suck »

Im surprised the Scott motor doesn't spec a larger clearance for the inlet with being built for track.
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Re: Ideal valve clearance

Post by RSVR »

T Scott is ya MAN.

DM's TS motor is running HRC cams, so without understanding the cam profile, and if the heads been skimmed which they most certainty have been, and thus the cam blocks shimmed up then, I would be having a wee chat with MR Scott himself. I will bow to T-Scott :worthy:

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Re: Ideal valve clearance

Post by CMSMJ1 »

The various HRC manuals have the valves set to a pretty wide spec - .20 for inlet if I remember rightly

I'd go wide for them mate..
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Re: Ideal valve clearance

Post by Drunkn Munky »

Mart, details of head skimming and shims for TS motor here
Image

Although what i really wanted to know is whats best for my spare motor which is stock RVF, and although its stock it'll only be used on track so i dont mind setting the valve clearences to a tighter tolerance range if thats whats best as i'll check it more often than i would a road bike.
CMSMJ1 wrote:The various HRC manuals have the valves set to a pretty wide spec - .20 for inlet if I remember rightly

I'd go wide for them mate..
Never thought to look in there, doh!
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Re: Ideal valve clearance

Post by Drunkn Munky »

RVF HRC manual states

Inlet .15mm to .20mm
Exhaust 25mm to 30mm

So looks like your bang on mark, as usual :peace:
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Re: Ideal valve clearance

Post by CMSMJ1 »

Drunkn Munky wrote:RVF HRC manual states

Inlet .15mm to .20mm
Exhaust 25mm to 30mm

So looks like your bang on mark, as usual :peace:
:oops:

I reckon I am on the autisitic spectrum..I do have some proper memory for numbers!

Looking forwards to this moto..going to be a sweet beast..and then finally will get down to Brands for a session
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Re: Ideal valve clearance

Post by lukemillar »

Interesting thread! I'm about to install my HRC cams, so was wondering the same info. Coincidentally, (more by shear luck than skill!) I have ended up with very similar specs as that TS spec sheet (main bearing clearances etc).

Couple of things that are interesting. TS has skimmed the heads + fitted the HRC pistons and longer rods. Also, I remember an old thread on TS head skim that claimed that he never shimmed the cam carriers and gear train! Haha - I guess this proves otherwise! ;)

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