Recent poor fuel economy

[pstelter]

Hope everyone's riding season is going well...

Two seasons ago, I rebuilt the carbs using Randakk's kit. )I also put larger jets for the main and pilot and put one spacer in the needle valves.) Only problems I have:

1. Could not follow the balance procedure as written because I could not get access to the #3 and #4 mix screws. (Supposed to adjust as part of the idle drop procedure.)

2. Fuel enrichment circuit is now sticky - releasing the choke doesn't do anything, I have to manually move the linkage once the lever is disengaged. Note - engine speed drops precipitously when I do this. Need to rev the throttle and it settles out again.

As expected with bigger jets, the fuel economy went down. I went from about 145 miles per tank to about 135 miles. That was pretty consistent from the time the carbs were re-installed and all of last season.

This year, gas mileage has gone through the floor. Now getting just over 100 miles to a tank. Engine seems to be running well in all other aspects.

I want to pull the carbs off to try and unstick the choke linkage and reset the small set screws to the factory position. Once I get them reset, I'll get a better tool for the idle drop test and re-balance the carbs.

Is there anything else I should be check to correct this fuel economy decrease? Should I replace the choke cable if it has been stretched out? Also, will I need new O-rings for any of the seals that I break? I'd rather not buy a whole new Randakk kit...

- Pete

[bs175dths]

You should not need a whole new kit, just bits and pieces if you deem the parts as not usable.

Assuming your riding style has been consistent, I find it interesting your mpg has dropped even more.....
You don't mention the kind of riding you do, all city, all highway, or an even mixture of both.
I do most of my riding on the highway and have noticed a decrease in mpg the faster I ride.
The best mileage I have achieved is 47mpg riding approximately 65-70 mph. I get 40 if I go faster but usually average 44ish mpg.
The sticky enrichment circuit may be either the piston (each carburetor has one piston) which slides open and closed, the linkage which connects each piston to the single cable, or the cable itself. It may also be a combination of two or all three features. Try lubricating the pistons while the carburetor assembly is still on the bike. It will take some repeated movement before you see any improvement. Lubricating the linkage can be done on the bike except for the linkage under the carburetor assembly. My became sticky and some WD-40 on each piston did the trick.
Poor gas mileage can be any number of things: riding style changed, terrain changed, the carburetors lost their sych., brakes are dragging, wheel bearings are dragging...... and maybe others I haven't mentioned because I am tired.
However, feel free to check the carburetors out, at least those could be eliminated as a culprit.
I am curious as to why you decided to change the primary, secondary AND add the washer.
Typically, the washer will help with the 'just off the throttle' stumble which may not change your mpg. Changing the primary and the secondary will definitely alter your mpg. You might consider changing the primary and secondary back to factory then set the mixture to factory and synchronize the carburetors to give you a good base point. I would leave in the washers as those shouldn't alter mpg noticeably.
If you are still not getting the kind of mpg you would like, check for dragging brakes or bearings. You may also be experiencing degrading coils, spark plug wires or spark plugs. Poor spark will also cause poor mpg.
It is going to take some time and experimentation so please be patient.

Good luck and attack the problem logically (take notes) so you don't spend time repeating yourself.

-Ride On