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Discussion Starter #1
This isn't exactly related to the ninja but I can't figure this out and won't sleep until I do lol. I know our Ninja's are DOHC 4-valves per cylinder but does that mean there are just two camshafts in our engine? I'm confused as to how an Inline 4 could have dual overhead cams and how a V-twin or parallel could as well...

Also for those motorcycles that are still 2 valves per cylinder (like the aprilia shiver), does this affect how many cams it has versus a 4-valve cylinder? (basically can one cam turn more than just 2 valves or does more than 2 valves per cylinder require at least 2 cams???)

I know this is a bit confusing but if anyone can help I might actually get some sleep tonight and not have to look like this tmrw :thud:
 

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Our bikes have 2 total cams. SV650's have 4 total cams, 2 per head. In a DOHC engine, a single cam will drive all intake valves in an inline engine and another will drive all exhaust valves.

I think a main difference is how the cam actuates the valves. In a SOHC, there are usually finger rockers but in a DOHC, the cam can push directly on the valve (through a shim and bucket setup). The direct pushing, the elimination of extra moving parts and the ability to prcisely nail down the timing differences between the intake and exhaust are probably what gives the commonly understood power improvement of a DOHC approach. I'm not an expert though.
 

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Johnny Blue Lightnin'
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Have you tried researching this. It would take a lot of typing to explain...
Try wikipedia for starters. Then once you have a basic understanding of those systems look up the various valvetrains used by Ducati. :thud:
 

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Discussion Starter #4
Ok... so did SOHC operate both the exhaust and intake valves then? It's hard to imagine this but it would make sense.
 

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Johnny Blue Lightnin'
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Yes, and they can operate more than one intake and exhaust valve depending on the application.
 

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Discussion Starter #6
Iave you tried researching this. It would take a lot of typing to explain...
Try wikipedia for starters. Then once you have a basic understanding of those systems look up the various valvetrains used by Ducati. :thud:
I have, and I understand the basic principle behind their difference I just can't picture it but I'm starting to get it now.
 
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