Runs rough cold, random hesitation..choke does not improve (if it aint' broke - dont fix it!)

[R. Lewis]

Could that be the same fix for my 2005 FXST, I was told to run the choke out alittle or the bike will pop. I just bought it and it has screamin eagle pipes on it and 3400 miles.

A properly tuned carb./scoot should not have to have the choke pulled out at all. ???????

 

[Caper]

If I remember correctly the recall on the carbs was the float valve...the original valve was a three sided one and was replaced with a 4 sided one and the Pos.battery cable was too short. Of course the dealer here gave me a "deer in the headlights look" when I asked about it

 

[Cambo]

Thanks for that tidbit of info. Caper, that is very interesting.. I did not realize the recall was on the float valve, rather I thought it was one of the jets. I am wondering if the mechanic messed up the height when he replaced...and now the carb is not filling up quickly enough hence high speed hesitation. I don't have a dial-guage to check the float height spec. Wonder if there is a way to check using a plain old measuring tape?

 

[fin_676]

Page 4-13 in the service manual covers float height using a ruler/tape measure
However as a rough rule of thumb for a quick test
stick a length of clear plastic tubing on the float bowl drain, (car window washer /fish tank airline hose)
tape it to the side of the carb open the drain screw and the fuel tap and you'll then get a visual level of the fuel level inside the float bowl
normally should be about 3/4 full
id suspect that yours will be below that

Brian

 

[jims87flh]

If that doesn't solve the problem..... You said they serviced a cable? Make sure your battery cables, and starter cables are tight. Mine used to run punk untill it got hot, because it was running on one cyclinder. Tightened the battery cable and Viola! runs like a champ again. (if thats the case, a quick inspection of the plugs should tell you, one will be sooty (or sootier)

 

[Cambo]

Page 4-13 in the service manual covers float height using a ruler/tape measure
However as a rough rule of thumb for a quick test
stick a length of clear plastic tubing on the float bowl drain, (car window washer /fish tank airline hose)
tape it to the side of the carb open the drain screw and the fuel tap and you'll then get a visual level of the fuel level inside the float bowl
normally should be about 3/4 full
id suspect that yours will be below that

Brian

I checked the float height with a vernier caliper and it was out of spec according to the manual...the float was sitting too high which would make the circuit too rich. This would explain the very black sooty plugs.... I bent the tab to put float within spec, however I am still having the same problem. I noticed some gas on the driveway when I got home, which tells me that either the needle is not seating correctly/not shutting off, or the float itself is still not high enough, or defective.

 

[Caper]

the float on your 91 is like a set of barbells(for lack of a better description) take a trouble light and hold the float in front of it to see if there is any gas in it, or you could submerge it in a tub of water to check it for leaks.

 

[Cambo]

the float on your 91 is like a set of barbells(for lack of a better description) take a trouble light and hold the float in front of it to see if there is any gas in it, or you could submerge it in a tub of water to check it for leaks.

I removed the float, did the water test and it check out perfect. I called the dealer to check on price of some of the parts and we got talking and the float spec. is different for the changed up recall 4 sided needle (15 -20 degrees .690 - .730 inches - good info. to know!)

Bottom line is she is still hesitating when cold, but runs like a charm when hot. Carb is still overflowing gas and plugs are black soot. My next step is to replace the carb drain needle and o-ring, just in case it is leaking versus incorrect float height. It was rusty and I cleaned up with fine grit sandpaper. Also my next step is to remove the mxiture needle plug and reset to spec.

 

[silentflyer]

Just think of the poor guys/gals who don't have a clue and just accept whatever the stealers tell them and write a check.............I hope they get a kiss out of the deal....

 

[Cambo]

Page 4-13 in the service manual covers float height using a ruler/tape measure
However as a rough rule of thumb for a quick test
stick a length of clear plastic tubing on the float bowl drain, (car window washer /fish tank airline hose)
tape it to the side of the carb open the drain screw and the fuel tap and you'll then get a visual level of the fuel level inside the float bowl
normally should be about 3/4 full
id suspect that yours will be below that

Brian

Thanks for the great tip -- I did this today to get the fuel level exactly at the bowl gasket mating surface. Can you please confirm if this is right on, or should the level be slightly below the point at which the bowl edge meets the carb body?