Nc30 quietening gears removal

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Neosophist
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Re: Nc30 quietening gears removal

Post by Neosophist » Sat Oct 11, 2014 1:09 pm

hunter wrote:If this is a race bike i would be supprised if they haven't been removed,
And if they haven't been removed then remove them,Because any gain is a gain.
And as the guy's have said the genny conversion is a bigger gain.
i wouldnt advice on just removing them, too much backlash might have a bad impact on the engine, nothing concrete, probably being more cautious than anything but the gains are minimal and its not easy to re-fit the backlash gears so if you ever come to sell the motor it will sound like a bag of spanners, not always a problem but it does put some people off.
xivlia wrote:i dont go fast on this bike so really do not need a rear brake.. /
vic-vtrvfr wrote:Ask xivlia for help, he's tackled just about every problem u could think of...

arsey30
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Re: Nc30 quietening gears removal

Post by arsey30 » Sat Oct 11, 2014 7:11 pm

The spring loaded back lash gear eliminates valve gear damage due to camshaft resonance. It also makes the cam gears run quieter, but with a whine.
If removed, the backlash needs to be set up accurately

There is another backlash gear on the lower gear in the gear drive cassette.

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skinnydog0_0
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Re: Nc30 quietening gears removal

Post by skinnydog0_0 » Sat Oct 11, 2014 8:18 pm

As this is a race engine i dont think mechanical sympathy is top priority.
I agree with all the points made with regard to the backlash etc, but racing is racing!
If i am spending £500+ for a weekends racing trashing an engine each season due to possible backlash issues seems a fair price to pay.
People spend $$$$ getting the bike lighter, getting trick fairings etc etc so why not do a mod that is free (like running total loss as has been mentioned)?
you can get a spare engine for under £300 so less than a weekends racing. If i am spending my hard earned for a weekends racing i want to beat the guys around me.
Whats the cost of a lithium battery? say £80? for what 0.05 seconds a lap if your lucky??? plus all the $$$$ for other parts to "make you go faster" you could easily spend over £300 for no real speed benefit.

What i would say is; If you are going to be racing in the same class as me-----
DONT do the mod, also run road tyres and a standard exhaust!!! I need all the help i can get :grin:
An NC is for life, not just for Christmas!

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Re: Nc30 quietening gears removal

Post by hunter » Sat Oct 11, 2014 10:39 pm

If it's good enough for Tony Scott it's good enough for me.

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VFRkieran
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Re: Nc30 quietening gears removal

Post by VFRkieran » Sat Oct 11, 2014 11:35 pm

As far as I know Tony Scott doesn't remove the quietening gears unless the backlash is well within spec. Mine are staying on the cams until I feel like I need more ponies or learn how to measure the backlash and know I can run without them reliably, has anyone actually seen or heard of an engine failure as a result of quietening gears removed?

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lukemillar
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Re: Nc30 quietening gears removal

Post by lukemillar » Sun Oct 12, 2014 12:16 am

Out of curiosity - Did Tony Scott build engines for short circuit racing or where the majority of his RC/NC builds for the TT etc?

hunter
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Re: Nc30 quietening gears removal

Post by hunter » Sun Oct 12, 2014 12:29 pm

As far as i'm aware when he was building engines for honda he removed the gears,
When i watched foggy and hislops bikes on short circuits and the I.O.M. the gears were removed,
When i bought my T.S. motor the gears had been removed.

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Re: Nc30 quietening gears removal

Post by arsey30 » Sun Oct 12, 2014 3:05 pm

The gears are then shimmed to obtain correct backlash.
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skinnydog0_0
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Re: Nc30 quietening gears removal

Post by skinnydog0_0 » Sun Oct 12, 2014 8:18 pm

I am no expert on the RC30 engine, but there are subtle differences between the RC and NC engines i believe?
I am pretty sure the cam gears on the RC are different (a bit like slotted cams?) and they dont run rocker arms?
Also i think the artical is showing the RC heads being skimmed ( I think i read this) wich will also have an effect on the valve train.
My understanding of the quitening gears is to 'pre-load' the main cam gears and remove any play at low revs.
If this is the case, (also bearing in mind the slight play in the rocker arms) i dont think at low revvs on a race bike this will cause too much if any extra wear on the engine, as the majority of the running will be at WOT.
If the engine is used for road and the occasional trackday, where you are cruising at mid revvs then perhaps there is a case for extra valve train wear, but for the milage a race engine does each year i dont think it will have any significant negative impact.
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Re: Nc30 quietening gears removal

Post by hunter » Sun Oct 12, 2014 8:29 pm

Correct,The shimming plays two parts,When the head is skimmed the valve clearance become very tight,
So you jack up the cam carriers to regain the clearance,And at the same time the shimming reduces the backlash when the gears removed.

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