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rc valve


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dunkenb

 
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rc valve

Sat Jun 21, 2008 6:23 pm » Post: #1 » Download Post

when the valve is closed where should the pointer on it be in relation to the pointer on the cylinder?
i ask as mine are to the right on start up, in the middle ticking over then over to the right again when the engine is revved?
seems arse about face but i could be having a blond moment??
Confused
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malc

 
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Sun Jun 22, 2008 9:54 am » Post: #2 » Download Post

Hi I had a similar problem with my rc valves not following a logical pattern ,revving the bike in neutral the valves were all over the place,'twitching' then I took the chain off and put the bike in gear and revved the valves then acted in a more logical manner. on the road the bike works well so i can only presume with my limited knowage that bike needs to be in gear rather than neutral to run the valves in the correct manner. see if that helps ,im sure someone on here can come up with answer
cheers Malc
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Dave Ett
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Sun Jun 22, 2008 11:34 am » Post: #3 » Download Post

I 'think' they jiggle about at idle to keep them from gumming up with carbon...
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Andy
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Sun Jun 22, 2008 1:55 pm » Post: #4 » Download Post

Not far off idle the RC Valves open to "Hi" or the setting position, then at around 3000rpm they move back to the "Lo" closed position. This is inherited from the MC16 model that had no T.P.S. and therefore no automatic way to set them up without the motor running.

If the idle is set to high, or the mixture isn't quite right, causing the RPM to wander slightly, or the idle RPM is set "just wrong" (i.e. on the edge of the lower set-up limit), then as the RPM increases the Valves will open. As they open, and as there's zero throttle, the motor will stutter very slightly, and the RPM will drop. Consequently, as the RPM drops, the motor falls back into its' comfortable range and settles down. As the RPM settles, the process will begin again.

If your idle is where it should be, i.e. around 1200 RPM, as you blip the throttle the RC Valves will be closed, briefly open, then close again. Once you get the revs up to around 7500 RPM they will re-open fully again.

I hope that explains it all?!
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Dave Ett
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Sun Jun 22, 2008 3:18 pm » Post: #5 » Download Post

Yes, except for why they open at all below high revs. What's to be gained?
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Andy
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Sun Jun 22, 2008 3:28 pm » Post: #6 » Download Post

Andy wrote:
Not far off idle the RC Valves open to "Hi" or the setting position, then at around 3000rpm they move back to the "Lo" closed position.

This is inherited from the MC16 model that had no T.P.S. and therefore no automatic way to set them up without the motor running.

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Dave Ett
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Sun Jun 22, 2008 5:02 pm » Post: #7 » Download Post

Where did that snippet come from? I only ask as it seems an odd throwback when they've gone to the trouble of inventing a new engine management system...
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Andy
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Sun Jun 22, 2008 5:13 pm » Post: #8 » Download Post

You live and learn, eh?! Wink

It's all a constant learning process, even after 13 years of NSR's. Slowly translating the official Honda Workshop Manual and collecting HRC books for the last 3 years all adds to the knowledge base.

Matt@TYGA and I share and swap a lot of info whenever we get together (before the rum or margaritas take too much of an effect... which normally means we forget some of it the following day!), but it's a shame that Steve no longer takes active participation in the Site as he was also into further development in a pretty big way.
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dunkenb

 
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Sun Jun 22, 2008 9:21 pm » Post: #9 » Download Post

cheers for the enlightenment! lol
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Dave Ett
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Sun Jun 22, 2008 9:31 pm » Post: #10 » Download Post

Ditto! Wink
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