LCGB Forums

My mate, whom I ride with regularly and did so going to Lincoln, is only getting barely 8 miles to the litre. His set up is 200 Mugello on small block, 26phbh with breath sweet filter and Ancillotti clubman. Not sure of his jetting however I did originally set the carb' up for him with AV266, 40 slide, 50 pilot, 100 main, X7, 300 float valve, 70 choke but he has had it dyno'd twice since, once with a st'd clubman at Scooterotica and then with the Ancillotti at Chiselspeed. The jetting set up has been changed, not sure for what but I believe an X13 needle has been put in and the main was upped to 110 at Scooterotica and then down to 105 at Chis'. I rode with him at exactly the same speeds, up to 60mph, and I got 10mpl plus (nearly11), on my TS1.

Comments appreciated please as we are a bit baffled by his high consumption,

thanks,

Rich'

leaking tap or tank ?

had a leak on a tank once but it only seemed to leak when it was ridden, seam on tank must have a very, very small hole that only leaked when vibrated.........and only when the tank was over half full.

Not seen any evidence of a leak like two stroke residue etc.

His standard tank full to brim went on reserve @ 48 miles.

Is he, ,quite large?

Rich Oswald wrote:His standard tank full to brim went on reserve @ 48 miles.

thats not a very scientific indicator.!


Fast flow taps are well known to go on reserve early
The reserve on fast flow fuel taps is simply a bit of plastic tube of pretty random length inserted in the centre of the fuel tap. I cut mine down slightly so that my tank doesn't go onto reserve too early.
Its a well known modification.

If you want to know exactly how much fuel an engine is using you need to ideally rig up a small header tank or fuel can and fill it with exactly 1 litre and see how many miles you get from it.You could shove 1 litre into the tank but it would be almost impossible to empty the tank completely on a run.

Aww come on guys,who really cares????
It does what it does,it a Lammy,not the most fuel efficient vehicle in the world

8mpl from mine consistently.
Full tank... do the miles, fill up and do the sums.
Now took the toolbox out and fitted a long range tank !!

229 ccs..heavily ported and piston skirt cut on inlet side.
30 mil Koso.
Expansion or Clubman (about 1/2 mpl better)

dave411 wrote:Aww come on guys,who really cares????
It does what it does,it a Lammy,not the most fuel efficient vehicle in the world

you'd sure care if your scoot suddenly run out of fuel at 60mph

There are several threads around explaining that the fast flow taps have a very long reserve tube which needs cutting down so that the reserve doesn't cuts in too early
http://scooterotica.org/forum/viewtopic.php?f=7&t=3470

I was running with a large pilot, I liked the security of some where rich to drop down to, returning less than 8 mpg, on slow runs I was always the first to need fuel.
On fast runs was comparable with similar powered bikes.
re-jetted dropped pilot and was suddenly the best on fuel 12 mpg.
careful jetting could make a big difference to economy.
I don't think a Dyno alone can do this. Al at Diablo was/is good as he does a decent test ride after and can pick up the things that a Dyno can miss.

Eden wrote:whats his timing set at? timing retarded for safe running makes it use more fuel.

That's interesting to know Eden.
So, if you have an advance/retard setup fitted, such as a Varitronic etc, would this mean the jetting would be larger than usual to safely run at say 15 degrees at full retard setting?
This would explain why I'm having to up-jet the carb so much to get the engine to run cool at high revs.

And don't forget the additional 200mls + of 2T when filling up.
5 litres becomes 5.2 litres.

Question for Eden. What consumption do you get? I know you do thousands of miles so your numbers must be pretty accurate. (Seen you filling up enough times in your videos !)

And don't forget the additional 200mls + of 2T when filling up.
5 litres becomes 5.2 litres.

Question for Eden. What consumption do you get? I know you do thousands of miles so your numbers must be pretty accurate. (Seen you filling up enough times in your videos !)

dave411 wrote:Is he, ,quite large?

No Dave, quite the opposite, lol.

CHRIS in MARGATE wrote:And don't forget the additional 200mls + of 2T when filling up.
5 litres becomes 5.2 litres.

Question for Eden. What consumption do you get? I know you do thousands of miles so your numbers must be pretty accurate. (Seen you filling up enough times in your videos !)

Suppose , taking the oil into consideration , that makes his fuel consumption even worse.

His timing is fixed at 19 degrees I think. The only thing I am certain about is that Martin at Chis' always leaves the jetting rich for safety.

Rich'

Mike Phoenix has just sent me a jetting for an identical set up and it appears even richer than what my mate has in:-

110 to 115 main, 55 pilot, AV 264 OR 266 ATOMISER, X7 NEEDLE ONE AND HALF FROM TOP, 250 FLOAT VALVE. CHEERS MIKE

Rich'

My S2 mugello 186 with 26 phbh, ram air filter and ancilotti returns 10-12 mpl depending on how hard I push it, I'm 6'3' and weight somewhere between 15 and 16 st so not exactly aerodynamic. From memory think it is 45 pilot, 45 slide, AV264, X2 needle, 100 main

Don't count the oil
It's lubricant not fuel

For the greater part your consumption levels indicate very good states of tune considering the power and performance you are making.
Are they all reed valve induction? If so, what reed valves are you using and do they give good clearance?
I ask because I am sure I can improve my fuel consumption that way.
Cheers for mpg figures.

Eden,
I'm quite New to this egt lark, and I run fixed timing at 17 degrees which I think is too retardedas my head temps are silly low.
But do you agree high but safe egt readings equal better economy