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1Back to top Go down   Specs RS vs Naked Please Explain Empty Specs RS vs Naked Please Explain on Sat Mar 09, 2013 8:48 pm

Bigsax

Bigsax
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So I am doing some bedtime reading last, the K100 Rider's Handbook (oh the K pox!) and was looking at the specs.

The naked does 56.5mpg @ 90kph. The RS does 65.7mpg @ 90kph & Rt 64.5.

The final drive ratio is naked 2.91:1. The RS 2.81:1 and RT 2.91:1.

# of teeth naked 32/11. Rs 31/11 and RT 32/11.

Weight (full tank), naked 239kg. RS 253kg and Rt 263kg.

So my question is, does the RS get better fuel economy because of of aerodynamics of the fairing? Or is it something to do with that missing tooth? It is carrying 14kg more!

I have just swapped my RS's handlebars from RS to RT, so with the more upright position and more drag will my fuel economy drop?


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Specs RS vs Naked Please Explain Brick110
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2Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sat Mar 09, 2013 9:02 pm

RicK G

RicK G
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I would expect the naked to do better than that. The wind resistance and fairing factor barely comes into the equasion at 90kph and will make minimal difference but the final drive ratio does make a noticeable difference to a K.
My wifes K75 went from about 59mpg to 67 mpg by changing the ratio from 3.2 to 2.91. I have a 2.75 to put into my K1100LT which has a 2.91 and expect to get a good improvement. I did hear of a guy who put a 2.56 ratio from a R1200c into a K1100RS and got a really big improvement.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

3Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sat Mar 09, 2013 9:09 pm

Bigsax

Bigsax
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@Rick G wrote:I would expect the naked to do better than that. The wind resistance and fairing factor barely comes into the equasion at 90kph and will make minimal difference but the final drive ratio does make a noticeable difference to a K.
My wifes K75 went from about 59mpg to 67 mpg by changing the ratio from 3.2 to 2.91. I have a 2.75 to put into my K1100LT which has a 2.91 and expect to get a good improvement. I did hear of a guy who put a 2.56 ratio from a R1200c into a K1100RS and got a really big improvement.


Any drop in power Rick?


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Specs RS vs Naked Please Explain Brick110
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4Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sat Mar 09, 2013 9:39 pm

RicK G

RicK G
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Yeah there will be but as with the K75 you don't really notice it after a few miles. Occasionally you need to kick it back to overtake but not very often. It was well worth doing.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

5Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sun Mar 10, 2013 4:28 pm

Tenox

Tenox
Life time member
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My bike is K100RT with no fairings at all. It consumption was last autumn something like 5,8l / 100km. It did not change much depending style of driving, but I did give old Goblin some action I admit. Bike has renewed (and a bit improved) engine and standard final drive (1986 model).

According to google this 5,8l / 100km is something like 40mpg - So I guess that the weight is not that important, but fairings and aerodynamics are.

Edit: Do you really get these bricks to go under 4l / 100km?? Over 600km (or 375 miles) without refuelling?

http://www.aqua-calc.com/convert/fuel-consumption/mile-per-gallon-to-liter-per-100-kilometer


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BMW K100RT Scrambler (86)
    

6Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sun Mar 10, 2013 7:13 pm

Comberjohn

Comberjohn
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Life time member
Find this thread interesting as I have just removed the fairing from my RT. (Fighting the urge to put it back at the moment as its 1C and snowing outside.)
I can feel the loss of that 24kg in the handling and performance when riding the bike but too early to say if the fuel consumption is much different.
I think we need to bear in mind when comparing fuel figures that US gallons are smaller than UK gallons.
Which type of gallon do you generally use in Australia?
Had considered using the higher geared RS diff but someone else had said the difference was negligible. Rick's comments are making me think again.

http://www.johnsdrivingschool.co
    

7Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sun Mar 10, 2013 9:03 pm

RicK G

RicK G
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Aust uses or at least used to use the imperial gallon but now it's the litre as do all except for US who use their special version of a gallon (where that came from I don't know).
In Aust we are restricted to 100kph which will return much better figures than places where the limit is 130kph or 80mph.
Despite the restrictions I have at times cruised at 130 -140kph for considerable distances and the drop off is astounding. At least 10mpg less.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

8Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sun Mar 10, 2013 9:27 pm

Bigsax

Bigsax
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@Rick G wrote:Aust uses or at least used to use the imperial gallon but now it's the litre as do all except for US who use their special version of a gallon (where that came from I don't know).
In Aust we are restricted to 100kph which will return much better figures than places where the limit is 130kph or 80mph.
Despite the restrictions I have at times cruised at 130 -140kph for considerable distances and the drop off is astounding. At least 10mpg less.

Dead right Rick.

The Riders Handbook states 4.3 l/100klm (65.7mpg) @ 90km/h (56mph) and goes to 5.7 l/100klm (49.6mpg) @ 120km/h (75mph).

Nearly 25% increase in fuel consumption!

I actually tested this out on my previous LT. I was on a 2600klm road trip and you need something to occupy your mind. The figures were within 2% of what is stated in the hand book. Bloody efficient those Germans! I also did a stretch at 140kph and the tank just about imploded the fuel was leaving it so fast!


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Specs RS vs Naked Please Explain Brick110
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9Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sun Mar 10, 2013 9:48 pm

klompy the grey brick

klompy the grey brick
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@Rick G wrote:Aust uses or at least used to use the imperial gallon but now it's the litre as do all except for US who use their special version of a gallon (where that came from I don't know).
apparently in the old days ships would deliver supplies to the American colonies and one of these consumables was rum in "one gallon" kegs....but yet again it was thought that the sailors would withdraw a specific amount from each drum prior to delivery so then the Americans had much smaller gallons....


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KKlompy Specs RS vs Naked Please Explain 2854237993
"Grace" 1984 K100RS Silver VIN 0019026 Mitt eine Staintune Zorst.
"Olivia" 1997 K1100LT Dark Grey VIN WB1052600W0237453.









Chassis number0019026
Vehicle code0503
SeriesK589
ModelK 100 RS 83 (0502 ( 0503 )
Body typeK 100 RS 83 (0502
Catalog modelECE
Production date1984 / 07
Engine0513)

Specs RS vs Naked Please Explain Au-log10


    

10Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sun Mar 10, 2013 10:07 pm

Bigsax

Bigsax
Gold member
Gold member
@Klompy the grey brick wrote:
@Rick G wrote:Aust uses or at least used to use the imperial gallon but now it's the litre as do all except for US who use their special version of a gallon (where that came from I don't know).
apparently in the old days ships would deliver supplies to the American colonies and one of these consumables was rum in "one gallon" kegs....but yet again it was thought that the sailors would withdraw a specific amount from each drum prior to delivery so then the Americans had much smaller gallons....

Wow Klompy, your memory goes way back Very Happy


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Specs RS vs Naked Please Explain Brick110
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11Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sun Mar 10, 2013 10:24 pm

klompy the grey brick

klompy the grey brick
VIP
VIP
ooohaaahhh Jim lad it were true....( splicing the main brace it were ) a tot for everyone, the colonials will never notice...hic, hic

until they start getting really crappy miles per gallon figures...


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KKlompy Specs RS vs Naked Please Explain 2854237993
"Grace" 1984 K100RS Silver VIN 0019026 Mitt eine Staintune Zorst.
"Olivia" 1997 K1100LT Dark Grey VIN WB1052600W0237453.









Chassis number0019026
Vehicle code0503
SeriesK589
ModelK 100 RS 83 (0502 ( 0503 )
Body typeK 100 RS 83 (0502
Catalog modelECE
Production date1984 / 07
Engine0513)

Specs RS vs Naked Please Explain Au-log10


    

12Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sun Mar 10, 2013 11:39 pm

TacKler

TacKler
Life time member
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@Klompy the grey brick wrote:
@Rick G wrote:Aust uses or at least used to use the imperial gallon but now it's the litre as do all except for US who use their special version of a gallon (where that came from I don't know).
apparently in the old days ships would deliver supplies to the American colonies and one of these consumables was rum in "one gallon" kegs....but yet again it was thought that the sailors would withdraw a specific amount from each drum prior to delivery so then the Americans had much smaller gallons....


Now I am getting confused. I went into local Total Wine & More over here in the US and I was able to buy my "Duty Free" Rum in cc measurement bottles. Nice and easy for a dumb ass like me. 3 x .75 litres means I am under the 2.25 litre limit upon return to the colony. I bought three bottles for the price of one at duty free prices at the airport. Specs RS vs Naked Please Explain 292303

Dave.


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Red 1991 K75S
    

13Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Sun Mar 10, 2013 11:59 pm

klompy the grey brick

klompy the grey brick
VIP
VIP
how times have changed...and it is time you updated your ownership list...Darth Tackler and his Matt Black K75RT....


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KKlompy Specs RS vs Naked Please Explain 2854237993
"Grace" 1984 K100RS Silver VIN 0019026 Mitt eine Staintune Zorst.
"Olivia" 1997 K1100LT Dark Grey VIN WB1052600W0237453.









Chassis number0019026
Vehicle code0503
SeriesK589
ModelK 100 RS 83 (0502 ( 0503 )
Body typeK 100 RS 83 (0502
Catalog modelECE
Production date1984 / 07
Engine0513)

Specs RS vs Naked Please Explain Au-log10


    

14Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Mon Mar 11, 2013 12:41 am

Tenox

Tenox
Life time member
Life time member
We in Finland have (summer) speed limits outside cities and towns etc. ranging from 60km/h to 120km/h. I usually drive those little roads with lots of curves, and not much cops. They range from 60 to 80, but I admit that I don't always drive excactly like the sign says...


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BMW K100RT Scrambler (86)
    

15Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Mon Mar 11, 2013 10:50 am

AJ.Valente

AJ.Valente
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@Tenox wrote:. . . I usually drive those little roads with lots of curves, and not much cops. ...
+1
That's were the fun is! bounce

    

16Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Mon Mar 11, 2013 10:58 am

92KK 84WW Olaf

92KK 84WW Olaf
Life time member
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I once learned the rum 'evaporated' through the wooden casks.....


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1992 K100LT 0193214 Bertha Alaska Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 103,800 miles
1983 K100RS 0011171 Fricka 606 29,495 miles Damn K Pox Its a Bat outta Hell Now 36,188  miles
    

17Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Mon Mar 11, 2013 6:22 pm

Themason

Themason
Platinum member
Platinum member
I have never seen better than 45 mpg out of any K100, and with the ethanol content of the fuel we are served today, my mileage is in the mid to high 30's, occasionally nudging 40 mpg if I exercise maximum adult restraint. A good old fashioned desert road hoon can drop the mileage down to 30 even.


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I live in a parallel universe but have a vacation home in reality :arrow:

1984 K-100RS Alaska Blue w/Parelever and 16V wheels.

1984 K-100RS Metallic Madison stock

1986 R-80G/S w/1000 cc engine

2007 Harley Davidson Street Rod Mirage Orange w/XR1200 wheels, Race Tech, True Track, Works Performance shocks

2007 Harley Davidson Street Rod Vivid Black stock

1993-ish K-100/1100RT/LT hemaphrodite frankenbike thingy to be painted satin black from a rattle can eventually
    

18Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Mon Mar 11, 2013 8:26 pm

Tenox

Tenox
Life time member
Life time member
We have 4 different fuels here (+ diesel of course)
RE85 (with 85% ethanol)
95E10 (with 10% ethanol)
98E5 (with 5%) I mainly use this, it is bit more expensive though.
Vpower = 99E5

Last one is sold only in few stations (Shell) and is the most expensive normal fuel in Finland.

Gas - buy the way - costs about 1,6 - 1,8 euros / litre here.. So it is little less than 40e for a full tank to K. (~50 US $)


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BMW K100RT Scrambler (86)
    

19Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Mon Mar 11, 2013 9:57 pm

japuentes

japuentes
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Hi there, what I've measured is 18.95km/l @115 km/h and 13.63km/l@140km/h.
Best regards
JAP


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Specs RS vs Naked Please Explain 2854237993 1988 K100RS SE/ABS
    

20Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Mon Mar 11, 2013 11:00 pm

K75cster

K75cster
Life time member
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I thought my K75 was good at 19.5kpl but when I changed the F/D to an rt's 2.91:1 I got 21.5kpl thats just going to work and back around 48k's each way back in them days. biggest difference though was in letting out the clutch we moved further faster in 1st than on the old F/D of 3.2:1 and quickly became obvious when doing a toyrun all that clutch in clutch out wasn't needed so much on the old F/D, cant imagine what the boys in motorcycle mags would have written about our bikes if they all came with a 3.2:1 f/d in 1983 they would certainly have got up and boogied in the stoplight stomp. The Mason's keep it at 7ooorpm would be easy with that F/D.


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Keith - 1987 K75c with r100rt replica fairing and half of a 1984 K100rt 1992 K1100LT a blue one

The Clever are adept at extricating themselves from situations that the wise would have avoided from the outset - QUOTE from david Hillel in Out of the Earth.
    

21Back to top Go down   Specs RS vs Naked Please Explain Empty Re: Specs RS vs Naked Please Explain on Tue Mar 12, 2013 2:18 am

AL-58

AL-58
Life time member
Life time member
I'm certain its mostly gearing.

When I exchanged the K100RS 16v paralever rear end for a K100RT Monolover rear, my sidecar went from getting 17km/l at 100-110kmh to 14km/l. I changed from an obnoxiously loud leaky 4-1 exhaust for a standard K100 exhaust at the same time.

Al


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'87 K100RS/HRD sidecar (1100 motor)  sc25 
'92 K100RS-16v (Paint it Black)

'87 K100RT with Paralever backend

"When I'm too old and too foolish to handle a sidecar I'll buy a Sportsbike"

Specs RS vs Naked Please Explain K-dogs10
    

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