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Another new rider question my bike is running around 4500 rpms on the freeway (65mph) is that normal.

Thanks
 

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Yes, the RPM's are correct. These engines are designed for higher Rpm's while cruising. At that RPM you should be getting better than 45 mpg on long runs if the engine is tuned right.
 

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bear,

That is what my vulcan cranks out at 60-65 mph. Also have an old 82 Maxim that pulls about 6k at 60 mph, and it will do that all day long. These bikes are designed to run at higher rpms, very different from cars. now when you start to pull 5500 rpms at 70-75 mph, now we are talkin!!!

Kevin
 

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Linkmeister Supreme
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Another new rider question my bike is running around 4500 rpms on the freeway (65mph) is that normal.

Thanks
The gearing ratios in 5th gear give the vn750 ~14.5 mph per 1,000 RPM.
14.5 mph X 4.5 ~ 65.5 mph. Your numbers are right on.:smiley_th
 

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Yup. it's correct. Main reason I bought my Meanstreak. I did 65 miles a day on the highway and REALLY needed a lower revving motor. The Meanie is 3750rpm at 75 mph, normal commuting speed.

Jon
 

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Mine does exactly 60 mph at 4000. And at that speed, I get mileage in the high 40s. But here in AZ the speed limit on freeways is 75, so I ride an indicated 80 mph, which is right on an actual 75. At that speed, fuel consumption goes up dramatically, and I get about 35 mpg. The high RPMs don't really bother me, but they can make you (me) feel a sense of urgency for some reason, which makes it a bit harder to relax. My Goldwing has the same feel at lower RPMs. It feels like it is turning faster than it is. The Harley on the other hand runs just over 3,000 rpm at an indicated 80, you can almost count the power pulses. IMO, it does not vibrate nearly as bad at that speed as most people claim. I still have all my fillings. It is a rubber mounted EVO, but not balanced. It does vibrate, but it is a much lower frequency vibration which will almost put you to sleep. Definitely my favorite highway bike for long trips. And it gets considerably better mileage than the Vulcan at an indicated 80 mph. The Goldwing (1200/four) gets 35 mpg no matter how you ride it.
 

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just a random thought. lol I have a 1998 Chevy Camaro Z-28. 6 speed manual tranny. 86 mph is 1,900 rpms in 6th gear. lol
 

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'03 VN750 "Rosie"
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bear,

That is what my vulcan cranks out at 60-65 mph. Also have an old 82 Maxim that pulls about 6k at 60 mph, and it will do that all day long. These bikes are designed to run at higher rpms, very different from cars. now when you start to pull 5500 rpms at 70-75 mph, now we are talkin!!!

Kevin
I got an 82 Maxim 400 back when it was two years old. I remember noticing the speed matching the rpm like that. I also remember the vibrations at 55 or above would make my legs numb before too long. I guess that's the difference between parallel twin and V twin engines?
 

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Headbanger/Popes of Hell
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Another new rider question my bike is running around 4500 rpms on the freeway (65mph) is that normal.

Thanks
if you up size your rear tire, it will drop your RPM's about 400 RPM's! :smiley_th
 

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if you up size your rear tire, it will drop your RPM's about 400 RPM's! :smiley_th
Is it any harder to fit the tire in there? Its a 180/70/15 right? I just put a Dunlop 404 on (about 70% tread left) and that was tight fitting it in there, i had to wiggle it alot, and thats the 150/90
 

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Back in '07, I bought a brand new Ninja 250 on closeout (last year of the old style) and it would cruise at 9000 rpm all day. Many people have put over 100,000 miles on those old style Ninja 250s at that speed. It was a small lightweight engine that was designed to spin. Before selling it because I really was too big for it, I swapped the front sprocket from a 14T to a 15T. That made a very noticeable difference. The Ninja 250 was one of those rare bikes that really was undergeared. The Vulcan 750 seems to be geared spot on. I have never found myself looking for another gear. If you think the Vulcan engine spins too fast at highway speeds, try riding a few hundred miles on the freeway on a Honda Rebel. It does not have a tach, but redline in each gear is marked on the speedo. Redline in top gear is an indicated 82.5 mph. I ride mine at wide open throttle up to an indicated 80 mph, just a hair below redline. I have done this for many thousands of miles, and except for slightly higher than normal oil consumption, have not had any problems. Others who have done this claim the engine has a lifespan of over 80,000 miles at those speeds, if it is properly maintained.
 

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Is it any harder to fit the tire in there? Its a 180/70/15 right? I just put a Dunlop 404 on (about 70% tread left) and that was tight fitting it in there, i had to wiggle it alot, and thats the 150/90
My '89 came to me with a 180 on the back. when i pulled it off to check and lube the splines it was a bit of a PITA to wiggle off and back on.

I just picked up a 140 that I'll be getting mounted and balance next week.
 

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Is it any harder to fit the tire in there? Its a 180/70/15 right? I just put a Dunlop 404 on (about 70% tread left) and that was tight fitting it in there, i had to wiggle it alot, and thats the 150/90
it will just fit. a lot of people let some air out of the tire when replacing them to help with the tight fit. but, they do fit.

after I replaced my rear tire with the next size up. not only did the RPM's drop at highway speeds, but it road way better! I love it and I will never put stock size tires on my VN750 again!
 

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I wouldn't mind having a larger diameter tire on the back, but I certainly wouldn't go any wider. IMO the rear tire is already too wide. My Road King has a 130/90-16 rear tire, and it is a much heavier bike than the Vulcan. The bigger the tire is, the more important perfect balance becomes, AND the harder it becomes to balance. I have seen it take over TWO POUNDS of weight to balance those big off road tires some idiots put on lifted trucks that they never drive off road with. Also, with bigger tires, you have more unsprung weight and more rotating mass, neither one is good.
 

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I have a 700, so run outta gears quick....wonder if a good machine shop could make a higher final drive gear for it....and honestly, for the power the bike has, all gearing is too low (F/O used to trail ride mine)...wonder if the driveshaft gearing could be changed like we used to swap drive sprockets on chain bikes ? Smaller rear sprocket, same [email protected] rpm. Used to do it often when I used to race. Almost wanna curse this driveshaft thing. Not "tweakable" enough.
 

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I feel the same way, this bike has plenty of power, I think if they made it with a higher 5th gear, all woulda been fine. cuz u would of had the same accel. in the other 4. Id like to see it turn about 4,000 at 65-70 in 5th gear.
 

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It may "feel" like it is turning too fast to some, but from an engineering point of view, it isn't. Those higher rpms give it more leverage. The main reason I would want to lower rpms on a truly undergeared bike would be to make the engine last longer. I seriously doubt it would make the Vulcan engine last longer. If the problem is buzziness, you must be more sensitive to that than I am. After 600 mile days on the Vulcan, I haven't noticed it being buzzy. I never get any tingling in my hands, even the right one. And the mirrors are crystal clear, even at speeds that would get you a whopper of a ticket.

I have heard that some Vulcan 750s came from the factory with their balancers out of phase, but the complaints seem to be too widespread for that to be the problem.

At ant rate, it is impossible to change the gearing, other than by changing the tire size. The Vulcans final drive housing was designed around the stock gearing, taller gears will not fit, even if you could get them, which you can't. They are specifically made just for that one particular bike.
 
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