Down on Power, Up on fuel Consumption!

[Ceirwan]

Having a bit of trouble with the Super S.
I'm only getting around 220miles to a tank, which when worked out is around 32-33 mpg, which IMO seems far too low, especially since a lot of my miles are dual carriageway at 60-65mph...

Need some idea's as to what it could be, pretty sure its not the plugs etc as they were changed just recently by the previous owner as was the distributor rotor arm etc. The air filter is clean too...

Pretty sure I should be getting at least another 10mpg, also the power seems down especially top end, it really has trouble getting to say 80, I remember when I had the K11 years ago that had no trouble doing 80 and the K10 has (supposedly) 6hp on top of that. (Similar mileage engines)

Any ideas appreciated

 

[kostas007]

check tyre pressure

 

[imp124]

one thing i didnt do was clean the carb out recently?

 

[Diskwiped]

my k10 did this for aweek or so, was really sudden, then just as quickly as it came it went, am i right in saying the standard hitachi carb is twin choke, cos if it is i think it has something to do with the second one ( when you push the pedal past about 3/4).
the difference felt like a turbo when it cleared itself up haha

 

[porkpie700]

Last time i had that problem it was because my fuel filter was full of crap, i changed that, the oil & oil filter and took it for a good run on the motorway. Ran beautiful after that, and yes you should be getting at least 50mpg so try squirting your carb with wd40 to make sure everything is free.

 

[Ceirwan]

Tyre pressures are fine, Will try some carb cleaner, cheers

 

[Shaun]

need to do this too! mpg is terrible bearing in mind i like driving quickly and have bigger rims on there.... if you saw my engine bay you'd know why it was down on mpg though!