New member and fuel efficiency

[Lucky_Lou]

Thanks Barry both Pete (the Admiral) and i are regularly doing nearly 60 mpg but that is with flat tops didnt realise there was such a big differance between a US gallon and an Imperial one, That makes price of gas almost reasonable here..... [smiley=cheesy.gif]
Lou

[Dizerens5]

"Imperial" gallon has a slightly colonialist sound, doesn't it? Over here the US gallon is sometimes called the Queen Anne gallon, which gives an idea of when the two became different sizes. Anne died in 1714 I believe. She gave her name to loads of other things too: QA architecture, QA fashions, QA furniture. And during her time she was sometimes called Brandy Anne, though maybe not to her face.

[Semper Gumby]

Hi Rory,

Nice R65!  Do a full tune-up and be prepared to go through the carbs.  Ask you questions here but you are not the first to disassemble the Flat-Top carbs.  Do some searching/reading about replacing the diaphrams,  checking the chokes, torquing the heads and setting the valves and timing.  On an older bike you will probably have to replace the needle jet and needles to get you mileage back to normal but there are many things to check first.

When you get to something you don't understand ---  ASK!  We have been there and are quite willing to help.

The only dumb question is the one not asked!

Do all that and then you can contemplate your first spline lube...

Welcome!

[zebedee]

When my 1984 R65 was relatively new, I used to get 17km/litre in urban riding and 20km/litre highway riding.

Carrying my 5'11" (1.8m) girlfriend as pillion generally reduced these figures by about 3km/litre.

These figures were pretty reliable and repeatable.

The best we ever saw was about 24km/litre on a highway ride two up, keeping to about 80km/h to allow a friend who was learning on his 250 to keep up.

Twenty years later I rarely if ever carry a pillion, the bike could do with some tuning, and I seem to get about 14km/litre.

[Barry]

When my 1984 R65 was relatively new, I used to get 17km/litre in urban riding

OK

multiply 17 by 4.546 that's  77.3 km per Imp gallon

multiply 77.3 by O.62137 that's 48 Imp MPG

add 20% to 48 and that's 57.6 US MPG


Only now do I understand you were getting good mileage !

No offence to Aussie members  - how come you guys gave up on good old miles. Litres I can understand
(but I love the US for not going metric).
km just makes the whole thing far too difficult for mental conversion.

Forgive me - I've spent a confused life doing mental arithmetic ever since being taught Woodwork at school in Imperial units and in the next lesson Metalwork in metric units.

[msbuck]

  

Forgive me - I've spent a confused life doing mental arithmetic ever since being taught Woodwork at school in Imperial units and in the next lesson Metalwork in metric units.

Barry - I'm glad YOU'RE doing the math here!  Thanks for the clarification.

[zebedee]

No offence to Aussie members  - how come you guys gave up on good old miles. Litres I can understand
(but I love the US for not going metric).
km just makes the whole thing far too difficult for mental conversion.

Forgive me - I've spent a confused life doing mental arithmetic ever since being taught Woodwork at school in Imperial units and in the next lesson Metalwork in metric units.

A) I was born in Cheshire, not Australia.
B) I was educated in Australia in both imperial and metric, so as you too should be, I am bilingual.
C) Have you ever tried doing physics or engineering in imperial units? Why on earth would anyone want to stick with imperial units?

[Barry]

Have you ever tried doing physics or engineering in imperial units? Why on earth would anyone want to stick with imperial units?  

I am an Engineer and you're quite right of course ... I was being a bit tongue in cheek.

I like to use old units on an old bike and if the UK ever changes to km (which it won't) I'll still be working out fuel consumption in MPG.

[Lucky_Lou]

When my 1984 R65 was relatively new, I used to get 17km/litre in urban riding

OK
multiply 17 by 4.546 that's  77.3 km per Imp gallon
multiply 77.3 by O.62137 that's 48 Imp MPG
add 20% to 48 and that's 57.6 US MPG
 just makes the whole thing far too difficult for mental conversion.

Barry i just took my shoes and socks of to work this out...surely you deduct 20% for USG  as USG are smaller than Imperial ?
Lou
Thread direction......sorry

[Barry]

Well spotted Lou.

I need to do a u turn

In fact it's divide 48 Imp MPG by 1.2 to give 40 US MPG

in which case 17 km/litre is ok but not so hot

See how confusing it is.  [smiley=dizzy2.gif]