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Discussion Starter #1
Readers digest version: The gas mileage on my '96 Trophy 1200 went from about 30 mpg to about 40 mpg (!) by dropping the carb needles 1 notch. (These are American gallons we're talking about.) Has anyone else seen similar results? Should I go another notch? I'd be interested in anyone's thoughts.

Here's the long version: I've bought my '96 Trophy 1200 about a year ago with 58,000 miles. It now has about 63,000 miles and has always got around 30 mpg. This was the most disappointing thing about the bike. For reference: the Concours I got rid of would get just under 40 mpg and my 1200 Kawasaki ZRX gets just over 40 and is faster than the Trophy.

It always seemed to run a little rich (throttle response slightly 'soft' and a little sooty around the ends of the exhaust pipes) so, when I had the carbs out recently to service the air filter, I dropped the needles 1 notch (from the middle notch to the 2nd from the top).

To be fair I also went from 20W50 oil to 10W40.

So after cleaning the air filter, changing the oil and dropping the needles, I have averaged 41 mpg on the last 3 tanks of gas. In addition, the throttle response seems better. I am happy, all is well with the world. :D

Rob
 

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My 02 1200 got 25 mpg. I found out the needles were raised to the highest point. I lowered them putting the c-clip on the top position and the bike would not take throttle. Way too lean. I lowered the c-clip to the #2 position from the top and I can get 50mpg if I go the speed limit on a long trip(not stop and go) Fortunately you can do this without removing the carbs. Good luck.
 

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Discussion Starter #4
Wow! And I thought I was doing good going from 30 mpg to 40 mpg. Its good to have some further confirmation.

Next time I have the tank off, I am going to try 1 more notch, which will put the needles at the leanest (top notch) setting. BTW, a friend says its possible to effectively adjust by smaller increments by using washers.
 

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wow - 50mpg....

i've just bought myself a carbtune and was going to do this over xmas....

i'm a bit of a newby to all this and not sure how to make the changes you talk about.... do you have any pics in addition to me reading the haynes?

ps - long distance is all i use this bike for, fully loaded trips round europe so mpg is important - expecially considering the £ is worthless right now :(
 

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Discussion Starter #6
I didn't take pictures, but it's not hard to do. I had the carbs out (which is a PIA), but according to Yanoosh, the carbs can be accessed without taking them off. Basically the tops of the carbs need to come off - 2 screws. Then there's a spring and the diaphragm/slide assembly. I think there was a spring seat gizmo and then the needle that will come out of the slide. The needle has a plastic washer that's a tight fit, and there is a c-clip that will be in one of the notches. Slide the washer out of the way and take the c-clip off the needle. Put the c-clip in a different notch, put it all back together the way it came apart. Repeat for the other 3 or 2 and you're done.

Mine were on the middle notch and I moved them up one notch (second notch from the top, same as Yanoosh). This moves the needle down, making the bike run leaner. The needles are tapered and fit through a needle jet. So moving them down makes a smaller area for gas to flow through.

Hope this helps. If I take mine apart again, I'll take pictures.
 

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Discussion Starter #8
I did not sync them after needle adjustment, but probably should have. I did not notice any difference in smoothness. Still buzzy like every other solid-mount inline 4 I've had.
 

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I should add that to get the #2 carb top off you need a screwdriver with a 90* bend in it. The frame is in the way of at least one screw. I also found it made the job faster to remove the coils and let them sit on the engine. Be careful not to drop the screws and make sure the o-ring for the vacume is still on the carb. I can probably remove everything and change the setting in about15-20 mins. So can you. Good luck.
 
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