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Misfire- The lady that interrupts... ????

"Running the bike 2 up the other day at speed, she had a hesitation with a small loss of power. I backed off the throttle and engine feels fine. Could this have been a misfire? Caused my the Omega system?..." Was the Question I asked over at the BOXERWORKS forums.

"Sounds more like fuel starvation to me ... electronics are stupid, they calculate from input rpm whether in 3rd 4th or 5th gear. Check fuel flow, float bowel level, both petcocks on under load etc......"

"Maybe your petcock screens are clogged with "stuff" or your fuel lines need replacing. The magic chemicals being added to gasoline now is cabable of really making a mess of various older "rubber" parts......"

My reply .... "Carbs have never been overhauled in the time I have had the bike. 3 years. So will check these over and see what might need replacing.

135 main jet is standard according to owners manual for 32mm Bings. I have had 145s fitted and had put the 135s back in for fuel economy reasons. 145s suck fuel so quickly at speed.

I will also have to check the fuel cocks to see if they are getting clogged up.

The bike starts first go no probs. Comes of the choke no porbs and runs well. Will rev through the rev range in each gear with gusto. Just in top and slowly winding her out that she hits this hesitation.

Thanks guys."


The floats heights were checked. They are good. Fuel tank drained and lots of gunk found in one of the in fuel cock filters. This was on the inside of the mesh filters.




Found this plastic bullet type thing with 4 weighs built into it in the tank. WTF?


Turns out the previous owner had put this into the tank. Took some fishing around with a bit of bent wire to get it out. This is a Fitch Fuel Catalyst. http://www.fitchcatalyst.com/recreational_vehicles.php 

The Fitch Fuel Catalyst Advantage


Increases Miles Per Gallon
Increases Horsepower & Torque
Quicker Throttle Response
Smoother Running Engine
Permanent Stabilizer for Off-Season Storage
Reduces or Eliminates Ping and Knock
Allows for a Lower Octane Fuel
One Time Application for the Life of the Engine
Good for 2 & 4 Stroke Engines

Yeah ok. I did not put it back in. 

So cleaned the the float bowls out and cleaned the fuel taps out. As I am putting the right hand throttle cable back on I stick my finger on some wire. Again WTF. I look down and the throttle cable is frayed not too far up from the nipple. I had suspected it was the right hand side that was playing up.


Looks like the frayed bits were catching and not allowing the right hand carb to open as far as the throttle grip was. This would explain the hesitation at the upper end of the bikes speed range.

I have had new throttle cables waiting to be fitted for about 12 months. They are now.

So new cables on and I have to balance the throttle cables. I have been shown to do this by ear. Yet I still can't get them right.

Yesterday. Huzzah!!!!!!!!!!!!! Took bike out to get warmed up. Set idle speed and idle mixture on side of road. Rode home. Put Carbmate on carbs.



One carb was so far out it was not funny. Tuned in the carbs. Took for ride. Rode very hard. Wow I love how she is now running. She feels the best in the whole time I have had her. Also got rid of the popping on over run.

Proves to me that I can not tune carbs by ear. I did this last week and really stuffed up the settings. Thankyou Carbmate.

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