[mjsharpe]

So I start up my 2005 Thruxton for the first time this year. It runs fine at idle, but the left cylinder is not producing any power at any throttle setting more than idle. The engine dies if either plug cap is removed. It's ridable, but only to a dealer! I am wondering if anybody has any comments or thoughts as to what the problem might be. I am thinking maybe a blocked jet ? I'm quite capable with a tool box, so I may have a go at fixing it myself. Also, what is the socket size for a plug wrench. I guess I need to take one to the grinder ! Any comments
or help would be greatly appreciated.

Thanks in advance.

 

[mikeinva]

Sounds like the carb has trash in it.Dont pull plug wires off when its running you can fry the coil. Both coils fire at the same time on your bike if you kill one you kill the other.pull both spark plugs and ground them and see if they both fire.The body of both plugs needs to be grounded.

 

[Baltobonneville]

Use a Craftsman 18mm spark plug socket.

 

[mjsharpe]

Spark Plug Socket

Re : Craftsman 18mm

Thanks...will I still need to grind it ?

 

[Baltobonneville]

No, it's the one that fits. Lowe's Kobalt brand 18mm looks to me like it's the same size (outside diameter), so that should fit too. It probably comes out of the same factory.

 

[mjsharpe]

Thanks for advice and latest news.

OK...Here is the story. I removed the float bowl on the faulty cylinder and found it dry. For comparison I removed the other float bowl and found it full of gas....hmmmm....something strange here, I thought.

I momentarily turned on the gas...and lo...the right carb spouted gas, and the left carb didn't. I rattled the left float...no change. I rattled it again...still no change. I rattled it a third time...and eureka....gas was now spouting from both carbs. Re-assembled the float bowls, turned on the gas, and pushed the starter. The famous Thruxton Grin formed from ear to ear as both cylinders thundered into life in perfect harmony.

Conclusion...I believe the float valve was stuck to its seating.

Now I'm off to get a plug wrench as specified by the second respondee to my initial post. Thanks again, and I think I'll ride the bike to Sears, or maybe Lowes...or perhaps both !! (He says as he disappears down the road in a cloud of dust, still wearing the aforementioned famous grin.)

 

[RedBird]

If it were me, I would also purchase a quart of Marvel Mystery Oil and pour it in the fuel tank.......good insurance against the same thing happening again soon.

 

[reflectedstatic]

No, it's the one that fits. Lowe's Kobalt brand 18mm looks to me like it's the same size (outside diameter), so that should fit too. It probably comes out of the same factory.

I know it's late, but just confirming that the Kobalt 18mm will fit. Or at least mine did, 'til I lost it.