So I've read a lot on this here situation. I have owned this bike now for about 3 weeks first tank I got right at 20 miles per gallon. I had a leak in the petcock diaphragm. I rebuilt the petcock "no more leaks" went thru another tank and got 23 mpgs.
I have had the carbs cleaned. We did not use the balance tool should this be done? I just added my first can of sea foam to this last tank. Waiting to see what it will do.
I also will be replacing the chain here in the next few days.
I have a lil bit of hesitation at the crack of the throttle as well.
The idle is set at about 1000 rpm's when warm.
Any ideas what I should check for to get my mileage right would be much appreciated.
Thanx guys

 

I just did the carb sync on my bike. I thought the bike was running ok (started fine idled ok) and I had "bench synced" the carbs. After the sync the difference was remarkable. #1 carb had almost no vacuum. I would also look at jet size. Do you know if a jet kit was installed?

 

To the best of my knowledge the bike is 100% stock.

 

Check you're running standard sprockets front and rear should be 17/42 probably the case but just something to eliminate.

Synchronising the carbs will make the bike engine more efficient and smoother giving better MPG.

What type of riding do you do? High speed highway, high revving twisties, commuting?

Also are we talking US gallons or Imperial gallons when you calculate the MPG?
US gallons are smaller so you'll get less miles from them.

Check your choke mechanism is moving freely and shutting off completely.

Take a look at the spark plugs to see if they're sooted-up due to over rich mixture.

Hope this helps.

 

I'm talking US gallons.
Choke is operating at full potential. Just had it adjusted when carbs where cleaned.
I am mostly commuting to and from work 5 miles and any extra riding I can throw in. I ride some what aggressive at the moment, being new to me and all. But still no where near the bikes potential.
I haven't pulled the plugs yet. I will be doing that this weekend. The kid I bought it from said it was tuned up 6 months ago. But I guess that doesn't necessarily mean new plugs.

 

I get about 35mpg from an imperial gallon. But that's hard back road riding, using high RPM's. 25 sounds quite bad

 

Just yanked plugs and they all looked good with the right gap. Kind of a brown and dry no wetness or carbon build up.

 

does sound poor consumption

my 87 does 40mpg (uk gallon) with mixed riding

Rob

 

I wonder if it's a CA bike and the plumbing is messed up.
Do you know if it's a CA bike? If so you may need to remove the plumbing.

 

I believe it is not a CA bike. But how do I tell for sure?