Wilsons Sandbox

Posted: **Wed Apr 24, 2002 10:15 am**

Hi Folks, I've only had my 2000 KLR for about 5 weeks, so admittedly I'm new to the bike. I've put almost 800 miles on it and intend to use it for touring/ camping as well as commuting. At my first fill-up I got about 53mpg. At my second, which included some spirited riding at higher rpms, I got about 50mpg. Since then I've put on a 16T front sprocket thinking that the slightly lower rpms would let the engine work less hard at a given speed and also slightly improve gas mileage. Now I've seen two posts from fellow owners that the 16T sprocket caused a 10mpg drop in fuel economy. This goes against what I would have thought, assuming that we're talking the same speeds. Now if you rode ~70mph before and ~90 after the swap, I can understand it. But the 16T sprocket should be a very subtle change at most, and I would have thought that it would be for the better in mpg. 1)My bike was running ~65mph at 4000rpm with the 15T sprocket. Now, with the 16T sprocket, 65mph is about 3750rpm. How could this result in 10 fewer mpg? 2)Let's say we're running 5000rpm with a 15T sprocket. At that rpm, the engine is using X amount of fuel per hour. Now we put on a 16T sprocket and run 5000 rpm. Would the engine not still be using the same amount of fuel per hour(it's turning the same rpms)? Plus, we're going marginally faster due to the gearing difference. So how can the larger sprocket reduce fuel economy? 3)Did you all re-jet at the same time that you changed sprockets? I haven't put enough miles on with the 16T sprocket to get an accurate/ equivalent reading, but I guess I'll find out soon enough. Meanwhile, I'm wondering if I'll be changing back to the 15T. Has everyone had these same results? Thanks for any input, Craig 2000 KLR Craig Fritts Huntsville, AL

Posted: **Wed Apr 24, 2002 10:36 am**

On Wed, 24 Apr 2002, Fritts, Craig L wrote:

>touring/ camping as well as commuting. At my first fill-up I got about >53mpg. At my second, which included some spirited riding at higher rpms, >I got about 50mpg. Since then I've put on a 16T front sprocket thinking >that the slightly lower rpms would let the engine work less hard at a >given speed and also slightly improve gas mileage. Now I've seen two >posts from fellow owners that the 16T sprocket caused a 10mpg drop in >fuel economy. This goes against what I would have thought, assuming that >we're talking the same speeds.

Went 15 to 16 a long time ago and didn't see any change in fuel economy. I did 57mpg recently with the pilot screw 2.5 turns out. Prolly would've hit 60mpg with stock carb settings.

Posted: **Wed Apr 24, 2002 1:14 pm**

Craig, I run the 16T and average 50-55mph depending on how I ride it...I got about the same with the 15, but love the way it rides now, on the highway. Joe in Kansas

--- In DSN_klr650@y..., "Fritts, Craig L" wrote: > Hi Folks, > I've only had my 2000 KLR for about 5 weeks, so admittedly I'm new to the bike. I've put almost 800 miles on it and intend to use it for touring/ camping as well as commuting. At my first fill-up I got about 53mpg. At my second, which included some spirited riding at higher rpms, I got about 50mpg. Since then I've put on a 16T front sprocket thinking that the slightly lower rpms would let the engine work less hard at a given speed and also slightly improve gas mileage. Now I've seen two posts from fellow owners that the 16T sprocket caused a 10mpg drop in fuel economy. This goes against what I would have thought, assuming that we're talking the same speeds. Now if you rode ~70mph before and ~90 after the swap, I can understand it. But the 16T sprocket should be a very subtle change at most, and I would have thought that it would be for the better in mpg. > > 1)My bike was running ~65mph at 4000rpm with the 15T sprocket. Now, with the 16T sprocket, 65mph is about 3750rpm. How could this result in 10 fewer mpg? > > 2)Let's say we're running 5000rpm with a 15T sprocket. At that rpm, the engine is using X amount of fuel per hour. Now we put on a 16T sprocket and run 5000 rpm. Would the engine not still be using the same amount of fuel per hour(it's turning the same rpms)? Plus, we're going marginally faster due to the gearing difference. So how can the larger sprocket reduce fuel economy? > > 3)Did you all re-jet at the same time that you changed sprockets? > > I haven't put enough miles on with the 16T sprocket to get an accurate/ equivalent reading, but I guess I'll find out soon enough. Meanwhile, I'm wondering if I'll be changing back to the 15T. Has everyone had these same results? > Thanks for any input, > Craig > 2000 KLR > > Craig Fritts > Huntsville, AL

Posted: **Wed Apr 24, 2002 1:20 pm**

if gas burned is proportional to RPMs then if you drive at the same speed with lower RPMs (because of the 16t) then you will burn less gas. The amount of saved gas will depend on the way you ride. if I actually knew something I could work out the maximum possible drop in mpg. barnaby. -----Original Message----- From: Fritts, Craig L [mailto:clfritts@...] Sent: Wednesday, April 24, 2002 8:06 AM To: DSN_klr650@yahoogroups.com Subject: [DSN_klr650] cruisin' speed , 16T sprocket = lower MPG? Hi Folks, I've only had my 2000 KLR for about 5 weeks, so admittedly I'm new to the bike. I've put almost 800 miles on it and intend to use it for touring/ camping as well as commuting. At my first fill-up I got about 53mpg. At my second, which included some spirited riding at higher rpms, I got about 50mpg. Since then I've put on a 16T front sprocket thinking that the slightly lower rpms would let the engine work less hard at a given speed and also slightly improve gas mileage. Now I've seen two posts from fellow owners that the 16T sprocket caused a 10mpg drop in fuel economy. This goes against what I would have thought, assuming that we're talking the same speeds. Now if you rode ~70mph before and ~90 after the swap, I can understand it. But the 16T sprocket should be a very subtle change at most, and I would have thought that it would be for the better in mpg. 1)My bike was running ~65mph at 4000rpm with the 15T sprocket. Now, with the 16T sprocket, 65mph is about 3750rpm. How could this result in 10 fewer mpg? 2)Let's say we're running 5000rpm with a 15T sprocket. At that rpm, the engine is using X amount of fuel per hour. Now we put on a 16T sprocket and run 5000 rpm. Would the engine not still be using the same amount of fuel per hour(it's turning the same rpms)? Plus, we're going marginally faster due to the gearing difference. So how can the larger sprocket reduce fuel economy? 3)Did you all re-jet at the same time that you changed sprockets? I haven't put enough miles on with the 16T sprocket to get an accurate/ equivalent reading, but I guess I'll find out soon enough. Meanwhile, I'm wondering if I'll be changing back to the 15T. Has everyone had these same results? Thanks for any input, Craig 2000 KLR Craig Fritts Huntsville, AL Checkout Dual Sport News at http://www.dualsportnews.com Be part of the Adventure! Visit the KLR650 archives at http://www.listquest.com/lq/search.html?ln=klr650 Post message: DSN_klr650@yahoogroups.com Subscribe: DSN_klr650-subscribe@yahoogroups.com Unsubscribe: DSN_klr650-unsubscribe@yahoogroups.com List owner: DSN_klr650-owner@yahoogroups.com Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

Posted: **Wed Apr 24, 2002 2:19 pm**

Hey Motorcycle Dan, help out a poor airdale here, will ya? It has been my experience that riding uphill into a head wind, fully loaded (the bike, not me) I get worse fuel economy than if I'm riding a naked bike with a tail wind going downhill. The Kawi mill is basically converting gas to horsepower. Can't there be situations where a bike requires more power (fuel) to maintain a given speed? I know with the trip computer on my Jeep, the indicated fuel economy will go as high as 99mpg on a steep downhill grade. Very little horsepower is required in that instance. To go up the same hill at the same speed, fuel economy goes way down. More horsepower (fuel) is required. Using that twisted logic, couldn't it be true that the bike's engine has to work just a little harder to maintain the same speed while revving lower? Specially at freeway speeds where it takes more horsepower to overcome wind resistance? Or am I so far out in left field that I should take up gardening? Bill A15

--- In DSN_klr650@y..., "Fritts, Craig L" wrote: > Hi Folks, > I've only had my 2000 KLR for about 5 weeks, so admittedly I'm new to the bike. I've put almost 800 miles on it and intend to use it for touring/ camping as well as commuting. At my first fill-up I got about 53mpg. At my second, which included some spirited riding at higher rpms, I got about 50mpg. Since then I've put on a 16T front sprocket thinking that the slightly lower rpms would let the engine work less hard at a given speed and also slightly improve gas mileage. Now I've seen two posts from fellow owners that the 16T sprocket caused a 10mpg drop in fuel economy. This goes against what I would have thought, assuming that we're talking the same speeds. Now if you rode ~70mph before and ~90 after the swap, I can understand it. But the 16T sprocket should be a very subtle change at most, and I would have thought that it would be for the better in mpg. > > 1)My bike was running ~65mph at 4000rpm with the 15T sprocket. Now, with the 16T sprocket, 65mph is about 3750rpm. How could this result in 10 fewer mpg? > > 2)Let's say we're running 5000rpm with a 15T sprocket. At that rpm, the engine is using X amount of fuel per hour. Now we put on a 16T sprocket and run 5000 rpm. Would the engine not still be using the same amount of fuel per hour(it's turning the same rpms)? Plus, we're going marginally faster due to the gearing difference. So how can the larger sprocket reduce fuel economy? > > 3)Did you all re-jet at the same time that you changed sprockets? > > I haven't put enough miles on with the 16T sprocket to get an accurate/ equivalent reading, but I guess I'll find out soon enough. Meanwhile, I'm wondering if I'll be changing back to the 15T. Has everyone had these same results? > Thanks for any input, > Craig > 2000 KLR > > Craig Fritts > Huntsville, AL

Posted: **Wed Apr 24, 2002 2:28 pm**

> 2)Let's say we're running 5000rpm with a 15T sprocket. At that rpm,

the engine is using X amount of fuel per hour. Now we put on a 16T sprocket and run 5000 rpm. Would the engine not still be using the same amount of fuel per hour(it's turning the same rpms)? too many variables. The object of final gearing is to put the engine in it's desired rpm range. If you ride a slower speeds, it takes less HP to fight wind resistance etc. Higher speed requires more HP. If you run higher speed with the engine in the same low rpm range it is not as efficient. You compensate by holding the throttle open farther and the combustion chamber gets a better gulp of air on the intake stroke and makes more HP by having higher combustion chamber pressure. So the main thing to do is find out what is right for YOU. Good ole Kawasaki can only shoot to please the middle of the crowd. It is we high end gear heads what think we simply must screw with every mechanical device we own. Dan /|\

Posted: **Wed Apr 24, 2002 2:33 pm**

>>>Since then I've put on a 16T front sprocket thinking that the

slightly lower rpms would let the engine work less hard at a given speed and also slightly improve gas mileage.

>>> 1)My bike was running ~65mph at 4000rpm with the 15T sprocket.

Now, with the 16T sprocket, 65mph is about 3750rpm. How could this result in 10 fewer mpg?

>>> 2)Let's say we're running 5000rpm with a 15T sprocket. At that

rpm, the engine is using X amount of fuel per hour. Now we put on a 16T sprocket and run 5000 rpm. Would the engine not still be using the same amount of fuel per hour(it's turning the same rpms)? ------- Craig, Your engine is actually working harder at any given speed with the 16T sprocket. You've geared it up, which will drop the revs but make it harder for the engine to pull a given gear. Try this experiment if you have a 10-speed or mountain bike: With the chain on the smallest front ring and the largest in the back, pedal for awhile--pretty easy, right? Now switch to the big ring up front (like putting on the 16T), and it gets harder for you, the engine, to turn the crank. Also, comparing revs at a given speed with no mention of the throttle opening necessary to produce those revs is only half an analysis. Same goes for fuel/hour argument: it may well take more gas for the engine to rev 5000 rpm in a given gear with the higher gearing. In the extreme case of overgearing, you could peg the throttle and never reach 5000 rpm. I would expect a 16T to give you better mileage for normal highway cruising (without major headwinds/crosswinds) because it essentially gives you an overdrive, but your in-town mileage could suffer because the motor has to work harder in every gear (imagine trying to ride that bicycle in only the big chain ring when you have to stop/go and climb hills). I ran one for awhile on my A1 and enjoyed the relaxed feeling of the bike on the highway, but now I have an A11 with the original gearing and I'm quite happy with it. If I decided to ride across the country, I'd change to 16. Hope this helps, __Arden Kysely

Posted: **Wed Apr 24, 2002 2:33 pm**

this is too funny we all decided to say this at the exact same time

Trev

--- In DSN_klr650@y..., "Motorcycle_Dan" wrote: > > 2)Let's say we're running 5000rpm with a 15T sprocket. At that rpm, > the engine is using X amount of fuel per hour. Now we put on a 16T > sprocket and run 5000 rpm. Would the engine not still be using the > same amount of fuel per hour(it's turning the same rpms)? > > too many variables. The object of final gearing is to put the engine > in it's desired rpm range. If you ride a slower speeds, it takes less > HP to fight wind resistance etc. Higher speed requires more HP. If > you run higher speed with the engine in the same low rpm range it is > not as efficient. You compensate by holding the throttle open farther > and the combustion chamber gets a better gulp of air on the intake > stroke and makes more HP by having higher combustion chamber pressure. > So the main thing to do is find out what is right for YOU. Good ole > Kawasaki can only shoot to please the middle of the crowd. It is we > high end gear heads what think we simply must screw with every > mechanical device we own. > Dan /|\

Posted: **Wed Apr 24, 2002 3:05 pm**

Lets say your engine produces enough power to keep you going at 50% throttle at 75mph at 5000 rpm then you change the gearing so your engine is in a lower powerband (I don't know I'm guessing at all of this) so then you are going 75mph at say 4500rpm but in order to do this you have to go up to 55% throttle maybe lower rpms but not always less gas. Put your car in 5th gear and try to go up a hill, your foot will be to the floor (lots of gas and low rpms) but not really going anywhere so less mpg. There are way to many variables to try to figure it out for real, wind resistance, friction, throttle position, carb tuning, all that kind of crap. Hope I confused yall more Trev A16 I don't really know anything either

--- In DSN_klr650@y..., "Barnaby Robson" wrote: > if gas burned is proportional to RPMs > then if you drive at the same speed with > lower RPMs (because of the 16t) then you > will burn less gas. > > The amount of saved gas will depend on the > way you ride. > > if I actually knew something I could work > out the maximum possible drop in mpg. > > barnaby. > > > > > > > > > > -----Original Message----- > From: Fritts, Craig L [mailto:clfritts@i...] > Sent: Wednesday, April 24, 2002 8:06 AM > To: DSN_klr650@y... > Subject: [DSN_klr650] cruisin' speed , 16T sprocket = lower MPG? > > > Hi Folks, > I've only had my 2000 KLR for about 5 weeks, so admittedly I'm new to the bike. I've put almost 800 miles on it and intend to use it for touring/ camping as well as commuting. At my first fill-up I got about 53mpg. At my second, which included some spirited riding at higher rpms, I got about 50mpg. Since then I've put on a 16T front sprocket thinking that the slightly lower rpms would let the engine work less hard at a given speed and also slightly improve gas mileage. Now I've seen two posts from fellow owners that the 16T sprocket caused a 10mpg drop in fuel economy. This goes against what I would have thought, assuming that we're talking the same speeds. Now if you rode ~70mph before and ~90 after the swap, I can understand it. But the 16T sprocket should be a very subtle change at most, and I would have thought that it would be for the better in mpg. > > 1)My bike was running ~65mph at 4000rpm with the 15T sprocket. Now, with the 16T sprocket, 65mph is about 3750rpm. How could this result in 10 fewer mpg? > > 2)Let's say we're running 5000rpm with a 15T sprocket. At that rpm, the engine is using X amount of fuel per hour. Now we put on a 16T sprocket and run 5000 rpm. Would the engine not still be using the same amount of fuel per hour(it's turning the same rpms)? Plus, we're going marginally faster due to the gearing difference. So how can the larger sprocket reduce fuel economy? > > 3)Did you all re-jet at the same time that you changed sprockets? > > I haven't put enough miles on with the 16T sprocket to get an accurate/ equivalent reading, but I guess I'll find out soon enough. Meanwhile, I'm wondering if I'll be changing back to the 15T. Has everyone had these same results? > Thanks for any input, > Craig > 2000 KLR > > Craig Fritts > Huntsville, AL > > Checkout Dual Sport News at > http://www.dualsportnews.com > Be part of the Adventure! > > Visit the KLR650 archives at > http://www.listquest.com/lq/search.html?ln=klr650 > > Post message: DSN_klr650@y... > Subscribe: DSN_klr650-subscribe@y... > Unsubscribe: DSN_klr650-unsubscribe@y... > List owner: DSN_klr650-owner@y... > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

Posted: **Wed Apr 24, 2002 3:07 pm**

okay that sucks I wrote this at like an hour ago

--- In DSN_klr650@y..., "kilrcalikawi" wrote: > Lets say your engine produces enough power to keep you going at 50% > throttle at 75mph at 5000 rpm > then you change the gearing so your engine is in a lower powerband (I > don't know I'm guessing at all of this) > so then you are going 75mph at say 4500rpm but in order to do this > you have to go up to 55% throttle > maybe lower rpms but not always less gas. > > Put your car in 5th gear and try to go up a hill, your foot will be > to the floor (lots of gas and low rpms) but not really going anywhere > so less mpg. There are way to many variables to try to figure it out > for real, wind resistance, friction, throttle position, carb tuning, > all that kind of crap. > > > > Hope I confused yall more > > > Trev > A16 > I don't really know anything either > > > > --- In DSN_klr650@y..., "Barnaby Robson" wrote: > > if gas burned is proportional to RPMs > > then if you drive at the same speed with > > lower RPMs (because of the 16t) then you > > will burn less gas. > > > > The amount of saved gas will depend on the > > way you ride. > > > > if I actually knew something I could work > > out the maximum possible drop in mpg. > > > > barnaby. > > > > > > > > > > > > > > > > > > > > -----Original Message----- > > From: Fritts, Craig L [mailto:clfritts@i...] > > Sent: Wednesday, April 24, 2002 8:06 AM > > To: DSN_klr650@y... > > Subject: [DSN_klr650] cruisin' speed , 16T sprocket = lower MPG? > > > > > > Hi Folks, > > I've only had my 2000 KLR for about 5 weeks, so admittedly I'm new > to the bike. I've put almost 800 miles on it and intend to use it for > touring/ camping as well as commuting. At my first fill-up I got > about 53mpg. At my second, which included some spirited riding at > higher rpms, I got about 50mpg. Since then I've put on a 16T front > sprocket thinking that the slightly lower rpms would let the engine > work less hard at a given speed and also slightly improve gas > mileage. Now I've seen two posts from fellow owners that the 16T > sprocket caused a 10mpg drop in fuel economy. This goes against what > I would have thought, assuming that we're talking the same speeds. > Now if you rode ~70mph before and ~90 after the swap, I can > understand it. But the 16T sprocket should be a very subtle change at > most, and I would have thought that it would be for the better in > mpg. > > > > 1)My bike was running ~65mph at 4000rpm with the 15T sprocket. Now, > with the 16T sprocket, 65mph is about 3750rpm. How could this result > in 10 fewer mpg? > > > > 2)Let's say we're running 5000rpm with a 15T sprocket. At that rpm, > the engine is using X amount of fuel per hour. Now we put on a 16T > sprocket and run 5000 rpm. Would the engine not still be using the > same amount of fuel per hour(it's turning the same rpms)? Plus, we're > going marginally faster due to the gearing difference. So how can the > larger sprocket reduce fuel economy? > > > > 3)Did you all re-jet at the same time that you changed sprockets? > > > > I haven't put enough miles on with the 16T sprocket to get an > accurate/ equivalent reading, but I guess I'll find out soon enough. > Meanwhile, I'm wondering if I'll be changing back to the 15T. Has > everyone had these same results? > > Thanks for any input, > > Craig > > 2000 KLR > > > > Craig Fritts > > Huntsville, AL > > > > Checkout Dual Sport News at > > http://www.dualsportnews.com > > Be part of the Adventure! > > > > Visit the KLR650 archives at > > http://www.listquest.com/lq/search.html?ln=klr650 > > > > Post message: DSN_klr650@y... > > Subscribe: DSN_klr650-subscribe@y... > > Unsubscribe: DSN_klr650-unsubscribe@y... > > List owner: DSN_klr650-owner@y... > > > > Your use of Yahoo! Groups is subject to > http://docs.yahoo.com/info/terms/

Wilsons Sandbox

editing a message - nklr

cruisin' speed , 16t sprocket = lower mpg?

cruisin' speed , 16t sprocket = lower mpg?

cruisin' speed , 16t sprocket = lower mpg?

cruisin' speed , 16t sprocket = lower mpg?

cruisin' speed , 16t sprocket = lower mpg?

cruisin' speed , 16t sprocket = lower mpg?

cruisin' speed , 16t sprocket = lower mpg?

cruisin' speed , 16t sprocket = lower mpg?

cruisin' speed , 16t sprocket = lower mpg?

cruisin' speed , 16t sprocket = lower mpg?