September 17th, 2016, 06:33 PM | #1 |
Daily Ninjette rider
Name: Hernan
Location: Florida
Join Date: Mar 2011 Motorcycle(s): 2007 Ninja 250 Posts: A lot.
MOTY - 2016, MOTM - Dec '12, Jan '14, Jan '15, May '16
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How VTEC works
Valves opening higher and longer at high rpm's: Easier breathing.
It was invented by Honda engineer Ikuo Kajitani. It has been used in motorcycles and cars. Copied from here: https://en.wikipedia.org/wiki/VTEC VTEC in motorcycles Apart from the Japanese market-only Honda CB400SF Super Four HYPER VTEC, introduced in 1999, the first worldwide implementation of VTEC technology in a motorcycle occurred with the introduction of Honda's VFR800 sportbike in 2002. Similar to the SOHC VTEC-E style, one intake valve remains closed until a threshold of 7000 RPM is reached, then the second valve is opened by an oil-pressure actuated pin. The dwell of the valves remains unchanged, as in the automobile VTEC-E, and little extra power is produced, but with a smoothing-out of the torque curve. Critics maintain that VTEC adds little to the VFR experience, while increasing the engine's complexity. Honda seemed to agree, as their VFR1200, a model announced in October 2009, came to replace the VFR800, which abandons the V-TEC concept in favor of a large capacity narrow-vee "unicam", i.e., SOHC, engine. However, the 2014 VFR800 reintroduced the VTEC system from the 2002-2009 VFR motorcycle. Honda incorporated the technology into the NC700 series, including the NC700D Integra (motorcycle/scooter hybrid), released in 2012, using a single camshaft to provide two timing routines for the intake valves.
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Motofool .................................Never ride faster than your guardian angel can fly "Mankind is composed of two sorts of men — those who love and create, and those who hate and destroy. Love is the bond between men, the way to teach and the center of the world." - José Martí |
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September 17th, 2016, 06:35 PM | #2 |
ninjette.org certified postwhore
Name: Rick
Location: Alexandria, Louisiana
Join Date: Jan 2009 Motorcycle(s): 05 Blue Ninja 250 Posts: Too much.
MOTY - 2017, MOTM - Jan '19, Oct '16, May '14
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Awesome! Thanks for sharing.
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September 18th, 2016, 05:17 AM | #3 |
dirty boy
Name: Joe
Location: Johnstown, PA
Join Date: Sep 2012 Motorcycle(s): I don't even know anymore?? Posts: A lot.
MOTM - Apr '14
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great info, i used to have a civic si that has vtec. Fun little car.
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September 18th, 2016, 07:13 AM | #4 |
Certifiable nontundrum
Name: Harper
Location: NC Milkshake stand
Join Date: Mar 2013 Motorcycle(s): 2013 SE NINJA 300 Posts: Too much.
MOTM - Sep '13, Sep '16
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When that vtech kicks in though
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September 18th, 2016, 07:35 AM | #5 |
n00bie to wannabie
Name: Bill
Location: St Ives, BC (Shuswap Lake)
Join Date: Sep 2015 Motorcycle(s): 2012 250R (Red), 2005 VFR800A (Red), CRF450X (Red), 2012 F800GS (Wants to be Red!) Posts: A lot.
MOTM - Nov '15
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I LOVE my VFR 800!!! The VTEC is an amazing kick. However; in so many of the corner speeds I have around here: it had a bad habit of initiating at the precise moment I would begin to roll on the throttle mid turn!!! I solved the problem (and the unplanned pucker!) by dropping the front sprocket one tooth. That had the effect of raising the engine RPM just enough so the VTEC was already initiated so there is no longer an unexpected surge of power at a critical moment!
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The Smart Money: #1 - ATGATT, #2 - Training (machine skills and survival skills), #3 - The bike; whatever floats yer boat with the money you have left over |
3 out of 3 members found this post helpful. |
September 18th, 2016, 01:55 PM | #6 |
Certifiable nontundrum
Name: Harper
Location: NC Milkshake stand
Join Date: Mar 2013 Motorcycle(s): 2013 SE NINJA 300 Posts: Too much.
MOTM - Sep '13, Sep '16
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Smart thinking!
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September 18th, 2016, 06:40 PM | #7 |
ninjette.org certified postwhore
Name: Eric
Location: Iowa City
Join Date: May 2009 Motorcycle(s): 2008 Kawmeracchi 350 2010 Project X Posts: A lot.
Blog Entries: 54
MOTM - Sep '18, Feb '16
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I had a VFR 800 and loved it. Everything about that bike was great.
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Top speed 123.369mph. Ohio mile Worlds fastest 250 ninja |
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September 18th, 2016, 07:52 PM | #8 |
The Corner Whisperer
Name: Chris (aka Reactor)
Location: Northern KY
Join Date: May 2011 Motorcycle(s): 2010 250 (track), 1992 250, 2006 R6 (street/track), 2008 R6 (track) Posts: Too much.
MOTY 2015, MOTM - Nov '12, Nov '13
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Mandatory graphic...
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Goal: Shake A Million Hands | Look through the corners | Track Day Prep | Closest track? | The Mid-Ohio School |
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