XS1100 (BS34s) Guzzles Gas, Runs Rich

[Jim]

Yeah... sounds about where mine used to be iirc. Unless I was doggin' it.

 

[grizld1]

Congrats! You caught that gremlin before it could fuel scour your cylinders! Now cage that rascal and poke it now and then to make it squeal; the others will hear it and keep their distance.

 

[jetmechmarty]

Great to hear Marty! Near 40 sounds like a healthy number for an XS1100.

I don't know anyone getting more.

 

[arcticXS]

Do you think it could cost me 5 mpg?

Easily. I experienced severe needle jet wear in a Ducati with the stock 38 mm Mikuni flatslide downdraft CV carbs, after approx. 40 000 km/25 000 miles, although I installed Dynojet needles somewhere around 20 000 km (some said that Dynojet needles were harder on the jets than oem Mikuni needles)
When looking through my worn needle jets, the orifice was sort of "pear shaped" (fitting description, eh?)
IIRC, my fuel consumption increased at least 20% with the worn jets, before I changed them.
So an old XS 11 can definitely suffer from that problem. And it is much more likely that the jet is worn, than the needle.

 

[jetmechmarty]

Easily. I experienced severe needle jet wear in a Ducati with the stock 38 mm Mikuni flatslide downdraft CV carbs, after approx. 40 000 km/25 000 miles, although I installed Dynojet needles somewhere around 20 000 km (some said that Dynojet needles were harder on the jets than oem Mikuni needles)
When looking through my worn needle jets, the orifice was sort of "pear shaped" (fitting description, eh?)
IIRC, my fuel consumption increased at least 20% with the worn jets, before I changed them.
So an old XS 11 can definitely suffer from that problem. And it is much more likely that the jet is worn, than the needle.

As it turns out, it was over 10 miles per gallon! I can not see the wear with my eyes. They look fine. I guess they aren't!