Author Topic: At any given speed, what RPM?  (Read 1727 times)

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Offline Scott S

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At any given speed, what RPM?
« on: July 18, 2010, 09:48:08 AM »
 After driving big parallel twins, a small bore 4 cylinder is a little different to me. On my maiden voyage today, I kept the bike between 4-5K rpm at any given speed in any gear. That's what seemed to make her happy. 3K or below and the power was weak and she wanted to stumble. Over 5K and she REALLY came to life!

 In normal driving, where do you like to keep the RPM's for best throttle response, charging system efficiency, etc? (My bike is a CB500, by the way)
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Offline cameron

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Re: At any given speed, what RPM?
« Reply #1 on: July 18, 2010, 10:50:21 AM »
I go for about that.. 4-5k.
1976 CB550F

Offline Hush

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Re: At any given speed, what RPM?
« Reply #2 on: July 18, 2010, 11:36:51 AM »
Our bikes only begin to charge the battery at over 3000 revs so maybe a battery charge before your next ride might be in order.
As you drop below 3k you start eating battery reserves.
I think the thing I most like about motorcycling is the speed at which my brain must process information at to avoid the numb skulls who are eating pies, playing the ukulele, applying make-up etc in the comfort of their airconditioned armchairs as they make random attempts to kill me!!!!!!!

Offline TwoTired

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Re: At any given speed, what RPM?
« Reply #3 on: July 18, 2010, 12:05:00 PM »
Take a look at safe area below red line.  Compare to twins.  You operate the twins at comparable RPMs and it will shake itself to death.

I don't like to get below 3500 while driving the 550.  Then I'm poised to downshift if any power is needed.  4-5K isn't a hardship for these engines.  They like it.  If you want serious acceleration power, go down 2-3 gears and you'll have it.
With the twins you can just twist the throttle.  With these bikes you work the trans to get spirited acceleration and don't be afraid of any RPM below the red on the tach.

It is also why I like quiet pipes on these bikes.  Normal driving and loud pipes draw police attention, even if you're driving within speed limits.
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Offline BeSeeingYou

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Re: At any given speed, what RPM?
« Reply #4 on: July 18, 2010, 12:22:35 PM »
I had to alter my driving habits after getting the Honda, coming from many years of owning an XS650 twin.  There the idea was to keep the revs down to a comfortable level.  I am usually in the 3-5K range and commonly shift around 4K with my 750F

Offline Raef

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Re: At any given speed, what RPM?
« Reply #5 on: July 18, 2010, 01:19:46 PM »
I ride a lot of country rodes and some highway, I find at highway speeds I am cruising around 5000 to 5500, as far as shifting goes I find myself reaching for the next gear in the 6-8K range.

 I don't ride that aggresive in town but I find my self riding in the 4 -5K range most of the time.

Mark

Offline Scott S

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Re: At any given speed, what RPM?
« Reply #6 on: July 18, 2010, 01:41:45 PM »
 Cool. So it sounds  like I'm in the normal range. I still have some tweaking and tuning to do before I get her to 100%, but it sounds like things are fine so far.

 On my XS650's, I always kept it at ~3500 or above, mostly b/c the charging system didn't work so well below that. Buckets of torque down low, but they'd be floating the valves ir running out of breath about the time these Hondas get happy!
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Offline bluezboy

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Re: At any given speed, what RPM?
« Reply #7 on: July 18, 2010, 04:15:21 PM »
 Like doooooh! Now  I see why my battery on my 750 is losing power even on a short 1 hour ride, I've been keeping the rpms' too darn low, some where around 1700-2500  only because I was worried about hurting my new baby.  So I guess I need to make her scream a little to get those charging juices flowing. Oops, sorry if what  just wrote sounds like bike porn, I didn't to, it just came out that way!

Offline Gordon

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Re: At any given speed, what RPM?
« Reply #8 on: July 18, 2010, 04:57:03 PM »
Like doooooh! Now  I see why my battery on my 750 is losing power even on a short 1 hour ride, I've been keeping the rpms' too darn low, some where around 1700-2500  only because I was worried about hurting my new baby.  So I guess I need to make her scream a little to get those charging juices flowing. Oops, sorry if what  just wrote sounds like bike porn, I didn't to, it just came out that way!

You're also most likely loading up your combustion chambers and spark plugs with soot. 

You been riding around in 5th at 25mph? ;D

Offline bluezboy

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Re: At any given speed, what RPM?
« Reply #9 on: July 19, 2010, 10:47:45 AM »
Like doooooh! Now  I see why my battery on my 750 is losing power even on a short 1 hour ride, I've been keeping the rpms' too darn low, some where around 1700-2500  only because I was worried about hurting my new baby.  So I guess I need to make her scream a little to get those charging juices flowing. Oops, sorry if what  just wrote sounds like bike porn, I didn't to, it just came out that way!

You're also most likely loading up your combustion chambers and spark plugs with soot. 

You been riding around in 5th at 25mph? ;D


No not quite, I've riding in 4th at about 35 or 40 which I realize now is the wrong gear for those speeds, so send me your shifting/speed pattern so this newbie can get this thing right. Thanks,vern

Offline flybox1

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Re: At any given speed, what RPM?
« Reply #10 on: July 19, 2010, 10:59:34 AM »
I ride a lot of country rodes and some highway, I find at highway speeds I am cruising around 5000 to 5500, as far as shifting goes I find myself reaching for the next gear in the 6-8K range.

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Offline Gordon

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Re: At any given speed, what RPM?
« Reply #11 on: July 19, 2010, 11:39:35 AM »
Like doooooh! Now  I see why my battery on my 750 is losing power even on a short 1 hour ride, I've been keeping the rpms' too darn low, some where around 1700-2500  only because I was worried about hurting my new baby.  So I guess I need to make her scream a little to get those charging juices flowing. Oops, sorry if what  just wrote sounds like bike porn, I didn't to, it just came out that way!

You're also most likely loading up your combustion chambers and spark plugs with soot. 

You been riding around in 5th at 25mph? ;D


No not quite, I've riding in 4th at about 35 or 40 which I realize now is the wrong gear for those speeds, so send me your shifting/speed pattern so this newbie can get this thing right. Thanks,vern


4th gear at 35 or 40 doesn't seem too off.  You sure your engine is running at 1700 - 2500 at that speed in 4th?  What 750 do you have and does it have the stock gearing? 

I don't make mental notes of the gear I'm in, the speed I'm going and the rpm the engine is at, but in town I generally keep my K1 between 3000-4500, and on the highway anything up to redline is fair game, especially when accelerating or passing.  There's nothing like the feeling of riding along at 60mph in 5th and dropping down to 3rd at WOT to pass another car. ;D