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I have a 1990 Goldwing GL1500 (transmission, 6 cyl, 1500cc) and a 2003 SilverWing (CVT, 2cyl, 600cc). At highway speed the GoldWing coasts like a car when you no longer apply throttle, while the SilverWing brakes like downshifting in a car (the deceleration of the SilverWing is very pronounced as comparted to the Goldwing). Why is that?? This does not present a problem as you get used to the handling of both; however, the difference is remarkable.
 

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I don't know how the 1500s are, but my 1200 decelerates as I let off the throttle being a manual transmission, same as my toyota 4runner with a manual transmission. It doesn't coast like a car does. When they put auto trannys in em, they will coast for sure! Of course, if I pull on the clutch, it does :action:
 

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There are huge differences in drive train geometry. The Sliverwing has a cc/lb ratio of 1.212 where the Gl1500 is 1.8.
The Sliverwing runs on 13 inch wheels the Gl1500 has 16 inch wheels. Think of the radius of the wheel like a lever trying to resist the weight of the bike. The Silverwing has a 10" (1/2 the tire D more or less) trying to work against about 700lb (bike + 200lb rider)compared to the Gl1500 12" working on about 1000 lb. the ratios are 70 for the Silverwing and 83 for the Gl1500. Figure in the displacement (ignoring compression ratio differences) SW 600/70 = 8.6 GL 1000/83 = 12. You can see that the numbers are diverging considerably. The last step would be the overall gear ratio between the crankshaft wheel but I don't have the numbers to go that far.

Steve
 

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SuperSkypilot wrote:
There are huge differences in drive train geometry. The Sliverwing has a cc/lb ratio of 1.212 where the Gl1500 is 1.8.
The Sliverwing runs on 13 inch wheels the Gl1500 has 16 inch wheels. Think of the radius of the wheel like a lever trying to resist the weight of the bike. The Silverwing has a 10" (1/2 the tire D more or less) trying to work against about 700lb (bike + 200lb rider)compared to the Gl1500 12" working on about 1000 lb. the ratios are 70 for the Silverwing and 83 for the Gl1500. Figure in the displacement (ignoring compression ratio differences) SW 600/70 = 8.6 GL 1000/83 = 12. You can see that the numbers are diverging considerably. The last step would be the overall gear ratio between the crankshaft wheel but I don't have the numbers to go that far.

Steve
A better way to look at this mite be that the SW has a force of 6000lb (weight X wheel radius) working on 600CC. the GW has a force of 12000 lb working on 1500 CC.

The Goldwing ratio is 8 lb of force per cc and the Silverwing is 10 lb per cc. ( ignoring the gear ratios )

There will be someone smarter along shortly to explain this better.

steve
 

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the silverwing has centrifugal clutch and CVT transmission while the goldwing has 5 speed manual transmission.

as soon as you release the throttle the clutch disengages and the rear wheel should spin freely although i am not aware if there is something designed to prevent so.
 

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William hit the nail on the head. If ideed the silverwing has a centrifical clutch it will be downshifting when you let the throttle off.
My new to me 1500 seems to just roll along if you let off the throttle way more so than my 1000 the 1100 is sorta between the 2 not shure why this is. Possibly due to the OD in 5th
Wilf
 

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The basic reason is simply that the CVT automatically continuously and smoothly"downshifts" while decelerating but the goldwing must be manually down shifted.

The CVT is not dissengaged until the centrifugal clutch dissengages (at some low rpm)...

This "automatic downshifting" isn't actually changing any gears, it is changing ratios "continuously" based upon speed and torque


Edit:wilf, you type faster than I.. the first part of william's statements are indeed correct, but the clutch does not disengage when you release the throttle... it stays engaged until the rpm of the engine isapproaching idle.
 

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Rarely do the springs and weights in the clutch allow the clutch to freewheel the CVT trans.

In practice, the engine is driving the rear wheel or the rear wheel is driving the engine. You can coax a shift (so to speak) by blipping the throttle with this set-up.

If you had a lot of freewheeling going on, then something is usually worn or your fluid needs changing.
 
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