49 Mpg (28.3 Kpl ) after new needle Jets

[mrclubike]

I just replaced the needle jets and now I am getting 49 miles per gallon  

I installed 2.64's like the fiche  called for but they were to lean in the mid (it had 2.66's in it from the factory but I didn't look at them before ordering
I have a pair of 2.66's on order but wanted to ride today
So I was going to drill them out to 2.66 but their is no # drill that size
So I turned the needle down  in a drill using some 220 grit
the off Idle is still a little lean but it runs OK otherwise
I am now getting 49 Miles per gallon (28.3 Kpl)
Is that A little on the lean side or is this normal for a well tuned carb  

[Bob_Roller]

Since 10% ethanol was introduced in the fuel supply here, 40 mpg is the best I can get .

We use the same fuel as required in southern California as well, I don't know if that has any effect or not .

I tried smaller main  jets 145 to 138 and saw no change in fuel consumption .

Using the same size needle jet as called out for by Bing, 2.66 and 241 needle . .

Before ethanol fuel and with 55 mph speed limits, I could get 45-50 mpg .

I'm not experimenting any more, with the intense heat here, I don't want to run too lean of a mixture and cause engine issues .

I need to use premium grade fuel during the hot season here, or detonation can  be an issue .

[Barry]

Mines an R45 so it's bound to get a little better MPG, on the other hand I'm hauling the same weight as an R65.  

Over the last 6 years of summer and winter use it's averaged 56 MPG (US). On a longer run in the summer it'll do 60 MPG (US). I'm on a 2.66 needle and the idle mixture is set relatively lean, By that I mean it's not set richer than it needs to be which I suspect many are. It's not so lean that there are any running problems at all. For example I don't need to use the enricher for an instant start in the summer months although of course it won't idle for a few miles.  My general feeling is that excessively lean mixtures don't provide the best MPG.

[Tony Smith]

Hang on, there is something interesting going on here.
 
An R65 has a 4.8 imp gallon tank or which .5 gal is reserve.



Therefore MrClubBike's 4.3gals at 49mpg equals 210.7 miles or 337km. Not shabby at all.


Barry is only getting 172 miles or 275km

I have been lamenting that my R65 running on 93 Octane (RON) unleaded has "only" been getting just over 310km from a tank at highway speeds. I think my R65 is running very nicely thank you.


By way of comparison, my KLE gets a mere 200km from 14lt or 125ml form 3.07 gals or 40.71mpg.

Now given that my KLE engine has a significant amount of ER5-N and ER6-N components in it and (to be honest) I thrash it unmercifully and it puts out more power than the R65 anyway (it should have 57 but with my mods I estimate high 60s) that ain't too shabby either.


BUT

I remember well by younger brother cruising in on his Honda firebird which was bettign those mileage figures by a L O N G  margin and had 150hp into the bargain. Or even the wife's new toy the G650GS which does more than 400km (250miles)  from 15lt (3.29gal) or 78.12 mpg.


My old Yamaha XT gets 420km from 22lt or 262.5 miles from 4.8gal or 54.68mpg which is about right given the load it has to shift and the "upright" seating and no aerodynamics.


Bloody 'ell that G650GS is good isn't it!

[Barry]

I like single cylinder engines. They are often good on fuel due to lower frictional losses and lower overall weight. I had a Suzuki GN400 single that weighed almost 100 lbs less than my R45, it wasn't much slower and would do 80 MPG.

Tony,

How am I only getting 172 miles out of 4.3 gals. I make it more like 289  

[Tony Smith]

I like single cylinder engines. They are often good on fuel due to lower frictional losses and lower overall weight. I had a Suzuki GN400 single that weighed almost 100 lbs less than my R45, it wasn't much slower and would do 80 MPG.

Tony,

How am I only getting 172 miles out of 4.3 gals. I make it more like 289  

Maths done too quick.

4.3gals * 56mpg = 240.8mi or  385.28km.


M'ok?

[Barry]

M'ok?  

Well nearly

56 MPG was in US gallons

In real gallons that's 67.25 MPG * 4.3  = 289 miles

[Billmc]

Finished up the refresh a couple of weeks ago and took it to the hill country last weekend and back. My 1st trip on her.  589 miles of highway, city, country and tight up and down twisties mixed and averaged 48.9mpg on 93 octane. 38 low and 57 high.  It sounds like your doing well.

[mrclubike]

Installed a set of 2.66 needle jets and a new set of needles (3rd notch)
It runs  good  but hunts a bit  at  55mph with neutral throttle
It will   get richer as the needle and jet wear in so I  will probably leave as is.
Next trip out i will check gas mileage  

[nhmaf]

I'm still running stock needles in my Bings (have to check the book to see what size, tho) and my recent trip out to Hamburg , NY for the BMWMOA rally averaged 45.6 MPG (US gallon).  Considering that about 500 miles of the ~1400 miles round trip was on the slab running at 70-77 MPH and I had a load of camping gear with me, I think it did well.  Plugs are a nice tan color and clean - I'm happy, too!

[Luca]

AFAIK I have stock jetting and I average about 43mpg doing my back-country sport riding.  When I would commute and do 80-85mph highway runs, I was getting about 40mpg.  When I keep speeds between 60 and 65mph I get closer to 47mpg.

Always fueled in 93 octane US gallons.