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pplassm · 08-05-2005, 09:04 AM

SAAB Sonnets and the like in the 70's had V-4's as well as the original Ford Capri.

BMW4VWW · 08-05-2005, 09:27 AM

If you're going to copy my posts you'll have to get old and grumpy first. VWW

blitz · 08-05-2005, 12:42 PM

Hi Van,

My kinematics book is in my attic, but I think you can have perfect primary balance with a 90 degree V6, or any V configuration with an even number of cylinders.

As I recall, primary balance has to do with the center of gravity not moving as an engine runs. A 90 degree V with 90 degree crank pins will not have its CG changed. (I just drew this out, and with crank pins 90 degrees apart, this holds true.)

Adding cylinders won't change the CG of the engine. If a 90 degree v twin has perfect primary balance, adding cylinders in multiples of two won't change the CG. It will, however, add rocking moments, therefor not providing secondary or higher order balance.

I'll caveat this again by "I think." It's been 22 years since I took kinematics, but I paid attention that day because it actually hit on something i was interested in. That was the one fact that stuck with me.

Thanks.

BMW4VWW · 08-05-2005, 05:20 PM

I believe that you are right about the secondary rocking couple ( as a long time BMW rider I of all people should have factored that in) however I am at a loss to explain why a 60 degree V6 with 120 crank throws is so much smoother than a 90 degree V6 if the primary balance is perfect and only the secondary balance spoils the smoothness. VWW

gmeline · 08-15-2005, 08:25 PM

Saw it at the Tokyo motorshow. Also, there's an article with pics on it in one of the more popular bike mags here in Japan (in Japanese, of course). 1800cc and pretty killer looking. Much less cruiser, more like the MT. Personally, I like the old one (get them while they last) for looks with some performance upgrades to boot.

dmiller779 · 08-16-2005, 05:22 PM

The 2005 Tokyo Motor Show isn't until October 21 so I assume that you saw it at the 2004 show. This is the first that I hear about Yamaha displaying the new 1800 V-Max. Can you provide a link so I can check it out?

Regards,

Doug

08-05-2005, 09:04 AM	#51
pplassm Founding Member Join Date: Nov 2001 Posts: 3,875	Re: On the 8th day God created the V-Max SAAB Sonnets and the like in the 70's had V-4's as well as the original Ford Capri. __________________ Mongo just pawn in game of life.

08-05-2005, 09:27 AM	#52
BMW4VWW Founding Member Join Date: Nov 2001 Posts: 1,833	Re: On the 8th day God created the V-Max If you're going to copy my posts you'll have to get old and grumpy first. VWW

08-05-2005, 12:42 PM	#53
blitz Founding Member Join Date: Jun 2007 Posts: 87	Re: KPaul was right,Take that back 90 deg V-4 is narrower and has perfect primary bal Hi Van, My kinematics book is in my attic, but I think you can have perfect primary balance with a 90 degree V6, or any V configuration with an even number of cylinders. As I recall, primary balance has to do with the center of gravity not moving as an engine runs. A 90 degree V with 90 degree crank pins will not have its CG changed. (I just drew this out, and with crank pins 90 degrees apart, this holds true.) Adding cylinders won't change the CG of the engine. If a 90 degree v twin has perfect primary balance, adding cylinders in multiples of two won't change the CG. It will, however, add rocking moments, therefor not providing secondary or higher order balance. I'll caveat this again by "I think." It's been 22 years since I took kinematics, but I paid attention that day because it actually hit on something i was interested in. That was the one fact that stuck with me. Thanks.

08-05-2005, 05:20 PM	#54
BMW4VWW Founding Member Join Date: Nov 2001 Posts: 1,833	Re: KPaul was right,Take that back 90 deg V-4 is narrower and has perfect primary bal I believe that you are right about the secondary rocking couple ( as a long time BMW rider I of all people should have factored that in) however I am at a loss to explain why a 60 degree V6 with 120 crank throws is so much smoother than a 90 degree V6 if the primary balance is perfect and only the secondary balance spoils the smoothness. VWW

08-15-2005, 08:25 PM	#55
gmeline Founding Member Join Date: Jun 2007 Posts: 3	Re: New V max in 2007? Saw it at the Tokyo motorshow. Also, there's an article with pics on it in one of the more popular bike mags here in Japan (in Japanese, of course). 1800cc and pretty killer looking. Much less cruiser, more like the MT. Personally, I like the old one (get them while they last) for looks with some performance upgrades to boot.

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08-16-2005, 05:22 PM	#56
dmiller779 Registered Member Join Date: Jun 2007 Posts: 3	Re: New V max in 2007? The 2005 Tokyo Motor Show isn't until October 21 so I assume that you saw it at the 2004 show. This is the first that I hear about Yamaha displaying the new 1800 V-Max. Can you provide a link so I can check it out? Regards, Doug