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Discussion Starter · #1 ·
Just curious. I took out my husbands brothers Victory the other weekend and it felt very top heavy, nice bike overall but I prefer the low center of gravity on the vrod.

What other cruisers out there have that low center of gravity feel?
 

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Guitar, not Gator
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Believe it or not, the "big" bikes like the Road King and Electra Glide feel low. It's one of the reasons you see them used for Police demonstrations. My Glide feels lower than my R (but R's sit a lot higher than most V-Rods)
 

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Softails give you the feeling of sitting in the bike. It's a very good handling model. All touring models feel low also.
 

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Nope, BMW twins and the laid over fours of the original K-bikes all have very low CG's. Look at those engines, the crank shafts are just about level with the axles, as are the gearboxes. The cylinder heads are parallel to the ground at the same height as the crank. There is very little weight above the crank on either, while all Harleys and transverse fours carry a lot of weight above the crank. Cylinder heads are heavy? In addition the line through the CG is very close to the bike's roll axis, the moment arm resisting your turning effort is very short. It is a core value at BMW Motorrad to build a bike this way. BMW's are longer and heavier than typical sport bikes but turn in quick and have neutral steering as a result.
Another thing overlooked is the gyroscopic effect of a spinning crank. On a bike with the crank mounted transversly, basically all the big V-twins and transverse fours are this way, the gyroscope that is that crank makes the bike hard to turn, especially when the revs are up. Many GP bikes used dual counter-rotating crank shafts ( Suzuki and Yamaha for example ) so the cranks countered each others gyroscopic effects and allowed the rider to turn the bike. Back in the day Kenny Roberts would complain that his arms pumped up from turning the bike and this is why. He was fighting that big gyro and it took physical effort to do. This is one of several reasons modern race bikes have very light cranks. By comparison, a BMW and a Moto Guzzi have longitudinal cranks, the crank is in line with the length of the bike. These have no effect on steering at all. So with a K-100/K-75 or any of the flat twins you have the dual virtues of a low CG centered around the bike's roll axis and a longitudinal crank, making these bike especially nice to corner for such long and comparatively heavy bikes.
Yes, I have a couple BMW's along with my Street Rod, and love them all.
 

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DanoRod, you might check out a Buell. They were the first I know of to use the swingarm as the oilbag and put the fuel under the seat; both intended to lower the CG. I've got a lot of miles on an XB12S, easily the best cornering machine I've been on. They are releasing the 1125R next month, a water cooled 155 hp beast.

Crusier? No. Lower CG? Absolutely
 

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Discussion Starter · #7 ·
coinpurse said:
Softails give you the feeling of sitting in the bike. It's a very good handling model. All touring models feel low also.

No way, at least the softtails I have ridden. They are extremely top heavy compared to the rod. The vegas rode very similar to a softtail. I think the closest to a softtail feel I ever rode was a VTX.

Is it the gas tank being under the seat on the vrod that gives it that low center of gravity feeling?
 

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Discussion Starter · #8 ·
Excellent info, the BMW's are super nice.

Philthy said:
Nope, BMW twins and the laid over fours of the original K-bikes all have very low CG's. Look at those engines, the crank shafts are just about level with the axles, as are the gearboxes. The cylinder heads are parallel to the ground at the same height as the crank. There is very little weight above the crank on either, while all Harleys and transverse fours carry a lot of weight above the crank. Cylinder heads are heavy? In addition the line through the CG is very close to the bike's roll axis, the moment arm resisting your turning effort is very short. It is a core value at BMW Motorrad to build a bike this way. BMW's are longer and heavier than typical sport bikes but turn in quick and have neutral steering as a result.
Another thing overlooked is the gyroscopic effect of a spinning crank. On a bike with the crank mounted transversly, basically all the big V-twins and transverse fours are this way, the gyroscope that is that crank makes the bike hard to turn, especially when the revs are up. Many GP bikes used dual counter-rotating crank shafts ( Suzuki and Yamaha for example ) so the cranks countered each others gyroscopic effects and allowed the rider to turn the bike. Back in the day Kenny Roberts would complain that his arms pumped up from turning the bike and this is why. He was fighting that big gyro and it took physical effort to do. This is one of several reasons modern race bikes have very light cranks. By comparison, a BMW and a Moto Guzzi have longitudinal cranks, the crank is in line with the length of the bike. These have no effect on steering at all. So with a K-100/K-75 or any of the flat twins you have the dual virtues of a low CG centered around the bike's roll axis and a longitudinal crank, making these bike especially nice to corner for such long and comparatively heavy bikes.
Yes, I have a couple BMW's along with my Street Rod, and love them all.
 

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Discussion Starter · #9 ·
ViagROD said:
DanoRod, you might check out a Buell. They were the first I know of to use the swingarm as the oilbag and put the fuel under the seat; both intended to lower the CG. I've got a lot of miles on an XB12S, easily the best cornering machine I've been on. They are releasing the 1125R next month, a water cooled 155 hp beast.

Crusier? No. Lower CG? Absolutely
They are nice also. But I still want to stay with a muscle cruiser, with my feet forward etc etc. It seems that there is nothing out there to beat the vrods very nicely balanced center of gravity. It's just a solidness and a feeling of being connected to the road.
 

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Last week I rode my 502 c.i. Boss Hoss around TN - it has a very low C-of-G and is extremely comfortable in that respect. Seat height is under 27" which helps as well.

Of course being so heavy it does not like to change direction quickly, so it would be disastrous to go into a corner too hot...
 

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Rollin' Hills
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IMHO---probably not many. To this day, my ridgid-frame 41 knucklehead, is the most down-into, pushin' bike I've ever had. I racked it out with an 18" extended springer,(and of course ruined the machine in the prosess), but at that point in time it was "cool", and " I was badd-ass". Funny how things change.:D
 

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It seems that there is nothing out there to beat the vrods very nicely balanced center of gravity. It's just a solidness and a feeling of being connected to the road.
+1
 

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Dynas have a low center of gravity in the HD line. I don't much like the touring bikes, personally. I rode a Road Glide 800+ miles one day. It was comfortable, but no real thrill at all. It was like driving a car.
 

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Shelby Stanga Rocks
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My wife can stand up my Vrod but not most other bikes. She is petie and it did take a good effort, but she could not stand up the "starter" bike a friend got.
 

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MOst of the standard cruisers have an inherent disadvantage.roughly 30-35 pounds of fuel sitting just behind the steering head and near the topmost part of the bike. Tends to make em a little top heavy right off the bat, especially when lifting them off the stand. not as noticable going down the road.
Ed
 
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