I just recently noticed that 5th gear seems short. Does this make sense to anyone?
Bike details: 2004 RR ABS 11k miles.
When shifting up from 4th to 5th I noticed that the RPM do not drop as much as shifting form 3rd to 4th or 5th to 6th. For example when shifting in 3rd gear at 4000 RPM if I shift to 4th the RPM reduce to nearly 3000, or pretty close to it. However when in 4th gear at 4000RPM if I shift to 5th gear the RPM reduce to only about 3500. 5th to 6th produces near 1000RPM drop similar to a 3rd to 4th shift.
Should this be setting off bells and whistles ? Hope I am just paranoid but.......
It's simply the way the gear ratios are setup in your gearbox. Don't worry about it if there was something wrong with your gear box you would know about it.
It can be hard to eplain gear boxes and ratios and how they work over the internet on a forum becuase it takes space and time to type all of that stuff. Do some internet reading and you will be good to go. As long as you have basic mechanical knowledge and common sense you should be able to decipher how gearboxes and gear ratios work farily easily.
This is a general overview on sequential gearboxes. Pretty much all Motorcycle gearboxes are sequential shift,with a few exceptions, meaning that if you want to go from 6th gear to 3rd gear or whatever you have to go though the gears before that one to get there. Unlike on a car gearbox where you can shift from high gear to low gear without going through every gear before or after that one.
zeke wrote:I just recently noticed that 5th gear seems short. Does this make sense to anyone?
Bike details: 2004 RR ABS 11k miles.
When shifting up from 4th to 5th I noticed that the RPM do not drop as much as shifting form 3rd to 4th or 5th to 6th. For example when shifting in 3rd gear at 4000 RPM if I shift to 4th the RPM reduce to nearly 3000, or pretty close to it. However when in 4th gear at 4000RPM if I shift to 5th gear the RPM reduce to only about 3500. 5th to 6th produces near 1000RPM drop similar to a 3rd to 4th shift.
Should this be setting off bells and whistles ? Hope I am just paranoid but.......
I think if you were shifting at 5000 this wouldn't bother you as much. I have a long uphill immediately following my entrance onto the freeway. I have to cross five lanes of traffic to reach the carpool lane, so I make the exit with power on and continue through the gears like the angel of death was in one of multitude of cars in that section of road. Shifting from 4th to 5th it continues to pull strongly. Usually I leave it in 5th until I reach safety in the carpoll lane and the road levels off a bit. The RPM drops off enough from 5th to 6th to discourage me from making that shift too early. I actually like that quick shift from 4-5 because it keeps me in a good place in the powerband. If I shift to 6th on that hill there's a serious loss of accelleration. I don't know if my `03 is geared the same as your `04, but I don't find the gear spacing troublesome except when I shift to 6th too early.
I don't get caught in the rain, I ride in it on purpose.
MikeCam wrote:The range (of the drive ratio) between 4th and 5th is small (0.261) compared to the ranges between 1st-2nd (0.841), 2-3rd (0.629), 3rd -4th (0.432).
You're also suggesting that the spacing from 5-6 is near what the spacing from 4-5 is. Am I reading that correctly ? if I remember the posts correctly, some of the models had a lower 6th gear. (Based on strictly unofficial RPM/speed) My bike runs 82mph at 4000 rpm, some of the others were nearly 500 rpm higher at that speed. If I shift from 5th to 6th at say 60 mph, it will just about stall. Needless to say, I am encouraged to speed so as to not lug the engine. My rpm drop from 5-6 is certainly more than 4-5.
I don't get caught in the rain, I ride in it on purpose.
Airman wrote:
My bike runs 82mph at 4000 rpm, some of the others were nearly 500 rpm higher at that speed. If I shift from 5th to 6th at say 60 mph, it will just about stall. Needless to say, I am encouraged to speed so as to not lug the engine. My rpm drop from 5-6 is certainly more than 4-5.
RPM to speed ratios vary based on a number of things, like wind resistance(ie drag), road surface, elevation changes, and such not. While the RPM drop from 5th to 6th gear is usually more noticeable, whatever speed one should make that gear change is entirely subjective. I've noticed that after I get my bike warmed up nicely (after about 10 minutes at around 80mph) the engine settles in at 3000rpm for approximately 70mph. However, when I'm accelerating to 70mph first thing, at 3000rpm, i'm only doing about 63. So the entire thing fluctuates a bit as you ride, but from what I understand, both 5th and 6th gears are "overdrive" gears and are equally capable of producing decent mileage (mine does about 190ish miles on a tank at about 80mph in 6th gear at 3700rpm).
Wind resistance and road conditions aren't going to affect the crusing RPM of a bike in a certain gear at a certain speed. Unless there is a large enough change in air temperature or athmospheric pressure to change the air pressure in the tires.
The only way to adjust RPMs at a given speed and gear selection is to change the final drive ratio, change the gearbox ratio, or change tire diameter. Also note a change in front tire diameter on bikes with a speedo driven by the front wheel, will also affect speed readings at a given speed and gear selection.
A change of tire diameter is probably why you are seeing those small diffrences in your speed to rpm in a given gear. Your tire picks up a little bit of air pressure when traveling down the road from friction of the tire and road heating the air in the tire. You can also change your effective ratio by changing out to a taller tire.
Following on from Airman's comment, I think some RRs must have different gearing....mine's a 2002 and at 60mph (100kph here in NZ) in 6th I'm running at 3500rpm....fine for me as the legal limit in NZ is 100kph which means it's pretty responsive for relaxed overtaking.
jeepinbanditrider wrote:Wind resistance and road conditions aren't going to affect the crusing RPM of a bike in a certain gear at a certain speed. Unless there is a large enough change in air temperature or athmospheric pressure to change the air pressure in the tires.
The only way to adjust RPMs at a given speed and gear selection is to change the final drive ratio, change the gearbox ratio, or change tire diameter. Also note a change in front tire diameter on bikes with a speedo driven by the front wheel, will also affect speed readings at a given speed and gear selection.
A change of tire diameter is probably why you are seeing those small diffrences in your speed to rpm in a given gear. Your tire picks up a little bit of air pressure when traveling down the road from friction of the tire and road heating the air in the tire. You can also change your effective ratio by changing out to a taller tire.
True, wind resistance and road conditions aren't going to affect much by themselves, but elevation changes (ie going up and down a hill) and weight like I mentioned, can and will. Besides, I have a hard time believing that slightly higher tire pressures are going to affect overall diameter enough to cause a 300-500 rpm change.
jeepinbanditrider wrote:Wind resistance and road conditions aren't going to affect the crusing RPM of a bike in a certain gear at a certain speed. Unless there is a large enough change in air temperature or athmospheric pressure to change the air pressure in the tires.
The only way to adjust RPMs at a given speed and gear selection is to change the final drive ratio, change the gearbox ratio, or change tire diameter. Also note a change in front tire diameter on bikes with a speedo driven by the front wheel, will also affect speed readings at a given speed and gear selection.
A change of tire diameter is probably why you are seeing those small diffrences in your speed to rpm in a given gear. Your tire picks up a little bit of air pressure when traveling down the road from friction of the tire and road heating the air in the tire. You can also change your effective ratio by changing out to a taller tire.
True, wind resistance and road conditions aren't going to affect much by themselves, but elevation changes (ie going up and down a hill) and weight like I mentioned, can and will. Besides, I have a hard time believing that slightly higher tire pressures are going to affect overall diameter enough to cause a 300-500 rpm change.
And all the 1150R's should have the same gearing.
None of it is going to affect anything at all unless you have a slipping clutch or an automatic transmission.
It's a solid mechanical connection when the clutch is engaged, unless again you have a slipping clutch or an automatic transmission with the torque converter unlocked (which is in effect a slipping clutch). None of the conditions you mentioned are going to affect the metal gears in the gearbox or final drive. They aren't going to change their ratios by going higher or going up a grade. Weight is not going to affect any drive ratios in the gearbox or final drive.
Like I said there is no possible way to change the RPM at a given speed in a manual transmission without changing ratios in the gearbox, final drive, or putting on a diffrent sized rear tire. And of course slipping of the clutch.
You WILL see minor differences in engine speed at a given gear selection and road speed between a cold and warm tire. Centrifugal force also acts on a tire and can cause it to get taller by a small amount.
AirForceDirt wrote:And all the 1150R's should have the same gearing.
They don't. Some bikes have the taller, "overdrive" sixth gear. Some don't. If your speed is just about double the tach -- that is, 4K RPM at 80 MPH, more or less, then you have the taller sixth.
It may have to do with the date of manufacture, or US vs. European model, but I dunno.
Green Hornet wrote:All
I am pretty sure that a "overdive" gear ration must be below 1 to 1.
My Guzzi has two ratios (4th&5th) that are below 1 to 1 .
Since our/my Rockster's ratios are over 1 to 1 there are no "overdrive" gears.
Micky
An "overdrive" is where the output shaft form the engine is larger than the shaft it is driving, thus the over part. This ends up being a ratio of 1:>1 or the way ratios are written, <1:1...such as the 5th and 6th gears on, for instance, my 04 1150r being .9 something and .8 something, these are actually .9:1. Meaning if the output shaft of the engine is always 1, because it does not change, the drive gear is a .9, or whatever it is for each gear.
Green Hornet wrote:All
I am pretty sure that a "overdive" gear ration must be below 1 to 1.
My Guzzi has two ratios (4th&5th) that are below 1 to 1 .
Since our/my Rockster's ratios are over 1 to 1 there are no "overdrive" gears.
Micky
An "overdrive" is where the output shaft form the engine is larger than the shaft it is driving, thus the over part. This ends up being a ratio of 1:>1 or the way ratios are written, <1:1...such as the 5th and 6th gears on, for instance, my 04 1150r being .9 something and .8 something, these are actually .9:1. Meaning if the output shaft of the engine is always 1, because it does not change, the drive gear is a .9, or whatever it is for each gear.
Overdrive has to deal with gear ratios. The bolded part is where I got confused reading your paragraph.
Overdrive is where the driven gear is turning faster than the drive gear. Gear ratios are written x:y where X is the drive gear and Y is the driven gear.
Take for instance a 1:1 ratio. This is as simple as it gets both gears that are meshed together are turning at the same speed as they are both the same size and have the same number of teeth.
When you start getting into lower gears the X number goes up over the Y number. The drive gear is turning faster than the driven gear. This is where you get torque multiplication and your able to operate the bike at lower speeds.
On the other end of that in the higher gears where the X is lower than the Y the drive gear is turning slower than the driven gear resulting in an "overdrive".
I was trying to simplify the concept to a very basic level, but rereading it, you're right, it is a bit confusing. I'll rephrase:
If you have two shafts connected via a chain, "overdrive" describes any situation in which the driving "gear" is spinning less than one revolution per the driven gears' one revolution. Thus drive ratios make more sense as a ratio of revolutions compared to each other. For example, a gear ratio of 2.5:1 would mean the drive gear is spinning 2.5 revolutions to the driven gears' 1.
None of it is going to affect anything at all unless you have a slipping clutch or an automatic transmission.
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Possibly true, but based on multiple weekends of 200+ mile jaunts to wherever (500 miles just this weekend, most of it on the super-slab) has given some hard observations to ignore. So if you have a better way to explain how my engine was spinning too different speeds for the same overall velocity, I'd love to hear it.
? Hope I am just paranoid but.......
