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My Honda Goldwing has a big engine, 1832 cc’s, which for me is the largest engine that I have ever had on a motorcycle. Not only do I like the ability to accelerate quickly from a stop, using the high torque of this 6 cylinder engine, but I really like that I can cruise the Interstate at a pretty good clip without having the engine screaming at me at super high rev’s. I was thinking about this yesterday while doing 80 to 85 mph on the Interstate and while the engine was not slouching, it was doing 4,000 to maybe 4,200 RPM. I well remember other bikes that seemed to be working super hard to maintain similar speeds, and how the seeming straining of the engine would make me feel strained and tired as well.

Part of what brought this to mind was in watching a YouTube video the other day from Jay Leno’s Garage where he was reviewing the Triumph Rocket with its 2,500 cc engine. He talked about how most American riders, it seemed to him, did not like the feel of high revving engines and did not appreciate that the engine was designed to run at those high rpms and that the riders that would under rev their engines were fooling themselves that they were taking better care of their bike than those that used the rev’s as designed. Maybe I am one of those folks that have never particularly enjoyed getting any bike that I owned up close to the bike’s redline, any more than I would enjoy a particularly noisy bike.

So being able to maintain a speed that is about as fast as one can go without undue risk of a big cost speeding ticket, without having to go to super high rev’s of the engine, seems to be a factor for me that makes me glad I have such a large engine. When I was riding a Triumph America with an engine about half the size of what I have now I could ride at 80 to 85, but I hated the sound and feel of making that engine rev so high to get to that speed. But maybe that’s just me.
 

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I think 🤔 but not positive, at 3,500rpms my bike would be doing 80+mph but it redlines at 5,200rpms so might be comparing apples to oranges. It’s been so long since I even looked at the tach that I’m not sure. I do know it darn sure isn’t hurting all the way to 100mph. After that it starts to wain a little.
 
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I grew up as a rider with 60's and 70' Hondas, and if you weren't running at high revs you weren't going anywhere, so I'm just fine with 6000rpm on my CB450 at a bit over 70mph. Yes, I like the power and reserve of my Valkyrie, but it's no stranger to 6000rpm either, albeit in the lower gears. It has seen 5000rpm in top gear, but that's in the neighborhood of 100mph, so not many times.
 

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Without considering the size of the bang, just think about the mass of the piston and rod, its relative speed, and the sudden stop in makes at the end of its travel. A slower reving 2 cylinder bike, with a longer stroke, is most often creating the most strain on parts, which includes the crank. Put your hand flat on the table, and wiggle your social finger up and down in short strokes. Now do the same in long strokes. You should notice the difference in speed attained, and stress on the joint.
For the farmers: Which pounds a post in the ground quicker. The old style slow large weight pounder, or the newer fast hitting hydraulic unit. UK
 

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Well, for Hondas at least, they are relatively short stroke engines: CB450 is 70x57.8, Valk 1500 is 71x64m and the GW 1800 is 74x71. That is probably reflected in the maximum rpm of each: about 9500 for the CB450 and 6500 for the Valk, and ~5850 for the GW (rev limiter).
 

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The problem with big engines is big weight. To me, light weight beats power. My current bike, a Honda cbr500r is the smallest I have had for awhile, but its 47 horsepower is proving to be adequate for solo riding. I still haven't hit redline on it, but when it gets to 7,000 rpm (redline is 8500), it makes some pretty good power.
 

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Your Goldwing has a legendary engine, that water cooled flat six is powerful and smooth as silk, and known to last forever.

I have a great pair to contrast:
My Vision with it's big 1740cc V twin is turning 3000 rpm at 80 mph. It sounds like it's just loafing along, happy as can be, not working hard at all. Redline is I think 5500 rpm, top speed in both 5th and 6th gear is governed to 119 mph, and it will easily go that fast, supposedly if the governor is disabled they can hit 130-140.

My Honda with it's little 400cc parallel twin is turning somewhere around 8000 rpm at that speed, screaming it's little head off, barely able to maintain that speed in 4th. I found that in fact it goes faster in 3rd gear than 4th, I hit just under 90 mph in 3rd gear, at around 10,000 rpm, which is also the Redline. It will hardly start to move the bike at 3000 rpm, the power starts around 5-6K.
 

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In the US, we like engines capacities on our two wheelers, that would be considered as suitable for a passenger vehicle carrying 6 in areas where motorcycles are a more dominant form of transport.

India is now the largest motorcycle market. Approx. 40 times more bikes are sold there on a yearly basis than are sold in the US, to a population roughly three times that of the US. The average bike is less than 250ccs and sells for less than $1500, brand new. Traffic speeds are lower than in the US. The average income in India was about 95,000 Rupees in 2019, which is about $1350 US. Gas prices are around $4.30/gallon. These numbers should make it obvious why fuel economy is MUCH more important to those people than it is to the average US rider. Where we might consider 40mpg as acceptable, they might consider anything less than 80 mpg as unacceptable.

My Royal Enfield 500cc single will return its full (2nd hand) purchase price over about 15,000 miles of commuting, as compared to the sedan I was using for that purpose previously. I ride a lot, but I don't ride for recreation. If I want to ride for fun or excercise, I choose a vehicle that looks more like this:
64412


Tell your grandchildren that they are very welcome.
 

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Discussion Starter #9
It is true we like big engines here in the U.S. I smile when I think about my motorcycle having a 1.8 liter engine while the first car I ever bought, a V.W. beetle, new in 1966, had a 1.3 liter engine. That Beetle cost me $1,900 out the door, new and including license and registration and sales tax in New York. My Goldwing new, 50 years after buying the Beetle, was a bit more than $1,900!
 
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I agree with what you said with people not liking the high revs. I ride a sport bike and coming from cruisers, I had to remind myself that the revs were fine for it and it's made to do it... not talking about holding it at redline but you get my drift.
 

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Big engine, big weight - hard to push with a flat. :rolleyes:
 

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The rpm you are running at compared to the mph traveling is not based on engine size, but gear ratio in the transmission, and front and rear sprocket ratios if you have a chain or belt type drive, or gear ratio in the shaft differential if you have a shaft, and tire circumference. That's why you can change tire size or the sprockets, and that will affect the speedo. When you do that, you have changed the final drive ratio. In order to maintain the lower rpm at the higher speeds, an engine with a lot of torque is needed. I'm not getting into the math here, just having a discussion. V Twins are known for lower rpm torque.
 

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Discussion Starter #13

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Discussion Starter #14
My Goldwing shows redline at 6000. I don't think I have ever been over 5000 in the four years I have had this bike.
 

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Big engines definitely have their advantages, but as someone said the weight and size can sometimes be problematic. Admittedly i'll be hittin that redline regardless if it's a Vmax or a 30cc ATV :)
 

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Power to weight is what matters. Yes, my Valk weighs in at over 900#, but it has the horsepower and torque to match. It's actually a little quicker than my much lighter VS800GL V-twin was, and a lot quicker than my even lighter CB450. Corners pretty well, too, in spite of the higher rake/trail numbers.
 

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RPM and speed are based on engine size, NOT the gear ratio. When it refers to small engines.
It is a matter of horsepower as WS said. Gear a small bike to do 5000 revs in top gear, and it will loose several miles per hour. They need to be geared to get maximum rpm in top gear. Raise the gear ratio and they will go slower, because they are off their maximum horsepower. Some engines have the maximum torque quite high. If the aim is to not quite reach the highest speed, then a slighter higher gear ratio can be used, to reduce the revs at say 60. Only the 400cc bikes and up, can get over 90. 47hp is enough to get into the nineties. The old 650 Triumph types ran about 45hp.
It is wind resistance at higher speeds, that needs more hp to overcome. A good fairing also helps, a lot. UK
 

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My M90 does 75mph in 2nd, and it gets there fast, don't know the rpm don't have a tach.......and it's fun to ride the curves in 2nd.

C90T is geared a bit higher, tuned different, and contrary to what I thought before buying, the engines are same size but not the same engine........ I've not run up the rpm on the C90T.........it is also fun running curves in 2nd and 3rd

Because of the much higher low end torque, the wide glide is a blast thru the curves in 3rd, I have run it up to 85 in 3rd, but that's not the fastest way to get there

My new gsx-s750, I have been running mostly 4000 with sometimes 5000rpm, today I ran over 500 miles and upped my rpm limit to 7000........3rd is 66mph 4th is 76mph.......redline is 11500

I can't see me running over 7000 unless I put a bigger sprocket on the rear........then flip it over on myself

My buddy rode it today, I told him to go ahead and give it some gas, shift at 7000
When we were done he said now I know the appeal
 

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RPM and speed are based on engine size, NOT the gear ratio. When it refers to small engines.
It is a matter of horsepower as WS said. Gear a small bike to do 5000 revs in top gear, and it will loose several miles per hour. They need to be geared to get maximum rpm in top gear. Raise the gear ratio and they will go slower, because they are off their maximum horsepower. Some engines have the maximum torque quite high. If the aim is to not quite reach the highest speed, then a slighter higher gear ratio can be used, to reduce the revs at say 60. Only the 400cc bikes and up, can get over 90. 47hp is enough to get into the nineties. The old 650 Triumph types ran about 45hp.
It is wind resistance at higher speeds, that needs more hp to overcome. A good fairing also helps, a lot. UK
I had an R3 which has a 321cc engine and the top speed is anywhere from 103-110 mph.
 
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