The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: ambrose78 on March 20, 2009, 02:52:01 AM
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Well I've had my bike for a couple of months and have now ridden about 3000kms. I would say my use is fairly typical, not wringing its neck off, cruising 100-120km/h on highways and generally puttering around town with the odd fang here or there just because.
My bike has returned:
a best of 6.5l/100km (36mpg US/ 43mpg UK)
a worst of 7.5l/100km (31mpg US/ 37mpg UK)
generally gets about 6.9l/100
It seems to me this is pretty high. Particularly when it gets up to 7.5l/100 as my car generally gets better than this.
Just wondering what everyone else is getting in the real world.
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I've got to be honest and say that I've never considered measuring. I know that I'm undoubtedly a rarity here......<thinks he may have to go out and test>
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I have to admit, that the higher of your two values is not atypical. However you might be able to improve things with a carb rebuild - new jets and needles. If it has not been done recently.
What colour are you plugs? Generally dark brown to slightly sooty means you are running rich. Light tan is good.
I normally got betwee 160 to 180 miles out of a tank with my Cafe Racer, but it mostly local mileage with a lot of town riding and wringing it neck out on the open road. On a long run I would expect up to 200 to a tank.
What that works out in mpg I do not know - as I have no centre stand I am probably not even filling my tank to the top!
Hope this helps.
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OK, I have to ask. What is "the odd fang here and there"? I'm stumped.
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The odd fang may be otherwise put;
Giving it a blat now and then,
Sometimes hammer it,
or
Occasionally opening the throttle hard.
It sounds like the sort of riding I myself do now that I'm in my 40's.
I ride sensibly most of the time but occasionally revert back into habits from my early 20's.
Man when I think back on my younger riding/driving habits how did I ever make to this age? :)
John
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My mileage tends to be more in the 40-45 MPG(US) range. My R75/6 doesn't do quite as well running about 35-40 MPG (US).
Of course when my fiance and I ride together the combined mileage for two vehicles is on the order of 22 MPG - about what my toyota gets but it is a lot more fun!
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Your fuel consumption is a bit on the high side.
Does your fuel contain 10% ethanol.
My '81 lost about 4-5 miles per gallon when the fuel supply changed from MTBE to 10% ethanol about 10 years ago.
Bing recommends that you replace the needle and needle jet at about 25,000 miles (41,000 km.).
It wouldn't be a bad idea to go through the carbs, and do a quick change of the rubber parts, along with the needle, and the needle jet.
I 're-built' the carbs on my '81 about 2 years ago, and I found that one of the needles was set to the wrong position ,from the factory.
If you are not the original owner, jet sizes, and needle position may have been changed from the factory specs.
Also, how accurate is your odometer ?
The odometers on these bikes are notorious for having problems.
Are you consistent in filling the fuel tank to the same level each time?
I use the bottom of the filler neck as a guide.
I was getting a consistent 220-225 miles (360-370 km.) to reserve,
now its around 200 miles (328 km.) to reserve with 10% ethanol in the fuel.
I guess this works out to be around 17 km/lt., or 5.9 lt/100km.
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... It sounds like the sort of riding I myself do now that I'm in my 40's...
John
John, you're still a young whipper-snapper. Don't you be dis'n us senior R65 riders. May have to give you a time out from the sandbox. [smiley=whip.gif]
Monte You'll be reading the back of my T-shirt Miller ;)
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If I am riding some distance and being fairly consistent/smooth about things, even riding at 100 km/h or a bit over I still generally get somewhere in the 40 - 45 MPG range. If I am doing numerous shorter trips, or doing some more 'spirited' backroad riding it may dip into the upper 30s, but I have never gotten less than around 36-37 MPG (US Gallon)
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Thanks for the input. Cheers.
I still generally get somewhere in the 40 - 45 MPG
I was getting a consistent 220-225 miles (360-370 km.) to reserve,
This sounds better. More riding less stopping at petrol stations.
I use the bottom of the filler neck as a guide.
That's what I have been using.
The first time I filled the bike I filled to the hole halfway up the filler neck. And then was rather alarmed to see petrol dripping over the spark plug leads at the next set of traffic lights as it must have been coming out the vent hole from being overfilled!! Since then no problems with the bottom of the filler neck.
Does your fuel contain 10% ethanol.
I generally avoid the 10% ethanol like the plague. Though I was forced to put ethanol fuel in the tank on the last fill as it was the only service station in the town I was at and had already hit reserve.
It wouldn't be a bad idea to go through the carbs, and do a quick change of the rubber parts, along with the needle, and the needle jet.
Sounds like the next thing to do. I'm not the original owner and don't have a service history for the bike.
Also, how accurate is your odometer ?
No Idea. I've never calibrated it. It seems reasonably consistent to what my car reads over similar journeys.
The odd fang may be otherwise put;
Giving it a blat now and then,
Sometimes hammer it,
or
Occasionally opening the throttle hard.
Spot on. The fun bit of the ride
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You mentioned an overflow of fuel after putting too much in the tank.
If you hadn't noticed, on the bottom of the tank on the left side there is a small pipe that comes off of the tank, if you put a length of hose on it, if you overfill it again, the fuel will go down the hose and avoid the hot engine parts !!!
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Yes, the overflow hose seems to be something that is most commonly missing from most of these bikes - I *think* that they came from the dealer with hoses, but since it adds another thing to remove whenever removing the tank, I am sure that many people thought "I'll just be careful when I fill the tank and be rid of it". I decided to put a hose back on (And route it back to the swingarm pivot area) to make sure that any overflows avoid all the electrical, sparky bits as well as the hot headers, etc. There is definitely a bit more miles available in the tank if one goes up a bit above the bottom of the filler neck, but I wouldn't recommend it unless one has an overflow hose installed "just in case".
I think it is a good safety tip for everyone to consider on their airhead.
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Well, I know my bike didn't come from the dealer with one installed.
The third fill-up after getting the bike, I overfilled the tank thanks to a pressure surge from a couple of other people that were refueling their cars, and shut off their nozzles at the same time.
I was engulfed in a cloud of vaporized fuel, as I had just had the bike out for a 2 hour ride, and the engine was as hot as it will ever get.
I installed the hose shortly after that.
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My only complaint with ethanol in our gas is that it seems to expand more as it warms. Like when I used to fill the bike up right before I get to work, and the gas expands up into the tank opening. On the BMW I can just smell gas as it goes out through that hole and the drain hose.
I'm repainting my Triumph tank this spring because it doesn't have one. I no longer fill up right before I'll be parking the bike.
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The fire danger of fuel overflowing onto a hot engine cannot be overemphasized. A fuel overflow drain should be a mandatory addition to your bike if not presently installed.
When purchased, both my R65s lacked this simple safety feature and I would not have been aware of its existence were it not for the this R65 forum.
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi196.photobucket.com%2Falbums%2Faa1%2Fmontmil%2FBMW%2520R65%2FTankOvrflo01.jpg&hash=57c030357531406decc325f4766534fb8a304ddc)
The tank's drain pipe extends vertically out of the tank bottom. I shortened a simple nylon 90 degree fitting so the drain line would remain tucked under the tank and out of sight. Vinyl tubing extends aft to...
(https://bmwr65.org/smf/proxy.php?request=http%3A%2F%2Fi196.photobucket.com%2Falbums%2Faa1%2Fmontmil%2FBMW%2520R65%2FTankOvrflo02.jpg&hash=fdfe5ee98888923bf06cd5c9eb187e451562a954)
...terminate with a short length of hard NylaFlo tubing. The hard tube fits through an existing hole in the rear footpeg bracket. Zip ties secure the routed line at a couple points.
BTW, a full fuel tank, even one that has not been over-filled, may vent fuel when parked in the sunshine for extended periods. The fuel expands when heated and will vent through the line.
Recip-powered aircraft are notorious for this. On hot Texas days, as I walk the ramp, I'll occasionally spot avgas dripping from wing tank vents. Just like with the BMW's, I stop fueling tanks at the base of the filler tube.
Monte
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While we are on a fuel topic, with the single fuel tap on the R65, there is about .5 gallons ( about 2 liters) of 'unusable' fuel trapped on the right side.
If you can get the front wheel elevated, like resting on a curb, you can coax the remaining fuel over to the left side,by tipping the bike to the left side.
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Or, if you leave a little bit of 'extra' length in your fuel line from the petcock, you may be able to slip the tank off the frame enough to tip it to the left without disconnecting it. It is a close call, and the last time I replaced my fuel line I didn't leave quite enough length
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It wouldn't be a bad idea to go through the carbs, and do a quick change of the rubber parts, along with the needle, and the needle jet.
I 're-built' the carbs on my '81 about 2 years ago, and I found that one of the needles was set to the wrong position ,from the factory.
If you are not the original owner, jet sizes, and needle position may have been changed from the factory specs.
I'm trying to obtain all the parts for the carb overhaul and have been successful with most parts ....except for the Jets.
Apparently there is a couple of listed jet specifications for the R65 - 2.64 and 2.66. There are also a whole pile of other sizes available that will fit the carbs but are probably too big or small. I've searched and searched but no joy.
How can one know which is the right one for the r65 bike? Or the merits of choosing one size over the another?
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At the front of the carb, there is a vertical web, and it has numbers stamped into it.
Like 64/32/325 for a left carb, and 64/32/326 for a right carb.
Get those numbers, and I can give you what was installed when the bike came out of the factory.
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found it
left side 64/ 32/ 307
right side 64/ 32/ 308
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The Bing manual shows a main jet size of 145, needle jet 2.64, jet needle 241, atomizer 591, idle jet 45 .
Needle clip position #4, the top slot is #1.
Hope it helps you find the sizes you need.
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Champion!
Thanks :)
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+1 on the overflow tube. I ran mine down infront of the LH cylinder. Simple and safer. ;)
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Well car rebuild is pretty much done now. So is the tank overflow tube. Now for a carb synchronizing tune.
On a side note, The airbox has a little rubber one way relief valve at the back near the battery.A pic of the little guy is at the bottom of this page.
http://www.gunsmoke.com/motorcycling/r100gs/carb_rebuild/index.html
Mine is pretty much in need of a replacement having gone hard and cracked. I called bmw and they want about A$25 which seems a lot for a little rubber grommet. Does anyone know of a reasonably priced supply?
Or alternatively if would there be a problem just sealing it up with some silicone?
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That 'fish mouth' looking rubber part, is there to drain water, or excess oil from the crankcase ventilation system that gets into the airbox.
As long as you take a look in there on occasion, I think you could plug the orifice with sealant, and not have any problems .
The cost of that part is 3-4 times the cost here in the US !!!!!
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I thought $25 was waaaaay too much for what is little more and an extended grommet. Particularly as the guy on gunsmoke said it cost him a few cents.
Where is good place to order the fish mouth airbox grommet from in the US?
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I apologize, I got the exchange rate incorrect, the cost in $25AU would be about $15US.
I used the British Pound, instead of the $AU.
Current price in the US is about $12US.
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Thanks anyway.
In that case I think I'm going to seal it up and periodically check the airbox. If anything goes wrong I can always put one in again in the future.
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If you wish to continue with the rubber vent mechanism, sorta, perhaps a bit of air filter element would work? Ol' Snowbum chats about this item in his BMW site. IIRC, he states it's a pressure relief or something...
Monte
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Just got back from a glorious ride up through the Royal National Park (Yay lots of twisties!! Just begging for a good fang :) ) , back along the highway at 110-120kmh with a bit of a trudge through Wollongong stopping at a few shops to get groceries, fuel etc
Initial riding impressions seem to be less throttle needed for a particular speed versus before
Anyway the first result is........ [size=12]5.9l/100 [/size](40mpg US 48mpg UK). Definitely the best yet :)!
Thanks again for the input ;)
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"How much fuel does your bike use?"
Well, my initial response when I saw this was, 'all of it!' but it got me thinking so I checked.
My riding is a mix of highway and urban roads, often congested with traffic, but there was a trip to race meeting that was 130km on a clear highway where I stuck to the speed limit of 120km/h.
I filled up again today and it took 14.3 litres to the bottom of the filler neck and distance covered was 266 kilometres which gives around 18km per litre.
Oh yes, fuel is R7.24 per litre (1 US$ = R8.80)
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Sounds like you guys have similar fuel prices to us. At the moment it is about A1.20 per litre. And $1US buys A$1.42
Fuel use continues to improve. Filled up after 220kms on a ride through the blue mountains @12l. Down to 5.5l/100. Very happy with that as it now will get close to 400km's on a tank.
Hopefully if this trend continues next fill will be 5.1l/100.
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Hi Aussie Pete
I covered the Bathurst 1000 in 1999. Hired a camper and got a site at the bottom of the mountain. I had a ball and have still got a 375ml can of VB on my desk!!
1 AU$ = 6.1 ZAR
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I covered the Bathurst 1000 in 1999. Hired a camper and got a site at the bottom of the mountain. I had a ball and have still got a 375ml can of VB on my desk!!
Steve, by "VB" are you referring to that wonderous nectar Victoria Bitter? That brew is fantastic but it just can't be found in the States. It seems that our palates tend toward "training beer".
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I usually get around 60 mpg (Imperial gallon). Of course that's when I don't have the bike torn apart for some reason.
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Ahh VB!! Victoria bitter. Sometimes known as vitamin beer. All I know is for a hard earned thirst...
With a carton of VB costing around A$45 these days, it costs more to run me that than the bike will ever use in fuel!!
Did you end up driving the course in the camper?
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Didn't drive it .... I walked it!!
Couldn't believe they also raced m/cycles there. Discovered that by reading some of the memorial plaques.
I think we hijacked this thread so I'll suggest something about an Ausie R65 economy run from Parramatta, Eastern Creek and up the Blue Mountains to Bathurst.
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The last 200 km was done with speeds up to 149 kph and on all kind of roads: 17.6 km per litre~5.68l/100km~387 km on a full tank~243 miles on a full tank.
Exchanging the choker control cable has done wonders for my economy, bettering my mileage with 10-15%. The engine runs like a dream now, idling away at 800 rpm and accelerating in fifth from 90 km/h to 130 km/h like never before. Wonderful!
Lesson learned: Always check your control cables before taking the whole engine apart.
greetings from a not very foggy or damp north (we have had easterly winds now for a month and temps above average)
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Exchanging the choker control cable has done wonders for my economy, bettering my mileage with 10-15%. The engine runs like a dream now, idling away at 800 rpm and accelerating in fifth from 90 km/h to 130 km/h like never before. Wonderful!
Choker cables eh? I've never used my coke so haven't condidered that they could be affecting it.. definately worth looking at.
I think we hijacked this thread so I'll suggest something about an Ausie R65 economy run from Parramatta, Eastern Creek and up the Blue Mountains to Bathurst.
I'm up for a run. I had a great ride up through the blue mountains just a coupld of weeks ago. The weather in autum is awesome - not too hot, not cold and clear air.
Anyone else keen?
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I got 13.6l for a 279km trip = 20,5km per litre or 4.97 litre per 100km in my 600km of riding last week.
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There must be something wrong with my carbs. My bike does not get more than 225km before reserve. This is about 8.5//100km. It is way too much
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Alchemist, I get the same as you, about 220 before going to reserve.
I run premium unleaded which is about 95/96 Octane and then stick in a squirt of upper cylinder lubricant.
Is it the bike age, I notice some bikes were rated different Kw. Around 81 I think it changed from 33Kw to 37KW, could this be the difference in mpg ?????
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Given correct jet sizes and needle position the usual culprits for excessive consumption are:-
Enricher not fully off
Worn needles and needle jets
float levels too high
Correct idle settings are important too. Our bikes use only 1/8 - 1/4 throttle most of the time even at modest freeway speeds so the mixture screw settings are still having some effect. If you think that doesn't sound right try using masking tape to mark out 1/4 1/2 3/4 and full throttle positions so you can see how much throttle you are using as you ride. The results may surprise you. I once improved my new 750 Bonneville from 45 MPG to 55 MPG just by adjusting the idle air screw which had been set very rich at the factory for running in.
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I'd have a good look at your carbs, if they haven't been gone through, it may be time to replace the needle jet, and all of the seals and gaskets and possibly the rubber diaphragms, check/adjust the float level, and condition of the floats, and the float needle rubber tip, and perform a thorough cleaning of the drilled passageways .
Check your 'choke' cables for proper adjustment, so the 'choke' isn't operating when you don't want it to .
Another remote possibility, how accurate is your odometer ?
When you refuel, do you fill it to the same level each time, like the bottom of the filler neck, with the bike on the center stand .
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My over flow tube (1/4" fuel line) runs straight down infornt of the LH cylinder next to the crank case and onto the ground. Simple.
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A year on after the carb rebuild and I'm hitting reserve generally around 330kms. The furthest I made it was 370kms before chickening out and putting in 19.1 litres.
I use name brand regular grade unleaded. No ethanol fuel if I can avoid it.
If you are hitting reserve at 220, try a tune up.
If that doesn't work then I definitely recommend paying the carbs some TLC. It took me about 3-4 hours of gentle tinkering about in the garage to fit.
Good luck with it.
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I still run my overflow drain hose in it's factory location ie: across the top of the motor to the right hand frame tube near the battery, down the frame tube and into the hole part way back along the top of the footpeg/muffler bracket just above the brake light switch.
When it overflows it does drip over the brake light switch and onto the exhaust pipe which always seemed a weird design??
I always run premium grade petrol, you should get more mpg from the better quality fuel. People that should know tell me that it is worth the extra $ for the higher octane fuel because of the extra miles you will get per tank.
I also believe it is better suited to our old style engines that were originally designed to run on leaded fuel.
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My bike uses A Lot of fuel*!
(as I ride it all the time!)
:D ;D 8-)
* - 87 oct with SeaFoam additive.
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My average fuel consumption now, is 200 miles (330 km) to reserve, before the addition of 10% ethanol to the fuel supply, my average to reserve was 225 miles (370km) .
Speed has a dramatic effect on mileage, when the national speed limit in the US was 55 mph (90km/h) I could get about 250 miles (410km) to reserve on rural limited access highways .
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"Speed has a dramatic effect on mileage, when the national speed limit in the US was 55 mph (90km/h) I could get about 250 miles (410km) to reserve on rural limited access highways ."
Thank you Ronald Reagan. (For raising it, though not enough.)