1974 tx650a Hesitation Issue

I think the easiest way to go about this is to remove the 10mm nut and little disc from the advance side then pull the rod out from the points side with the points cam still attached to it. The rest of the advance unit can remain in place. There is a little lip on the back of the points cam that may catch on the points sets rubbing blocks. You may need to pry the points sets open to get the cam and rod to slide out. Once removed, that will give you access to both sides so you can clean and lube the bushings. The factory recommends a grease with moly in it.

A note on re-installation and alignment. If you look at the advance before you take it apart, you'll see a couple alignment slash marks, one on the little disc and another on the advance unit backing plate (yellow arrows below). These should point to one another, or very nearly do so .....

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There is a locating pin for the little disc in the advance rod (green arrow above). The hole for that pin goes all the way through the rod so it's possible to install it in 2 different positions 180° off. Only one will give the correct alignment, the other will throw the timing off 180°. There's also a second way to check the alignment. The points cam has a locating pin as well. It should point in the same direction as the advance disc one does .....

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While the advance rod is out, you can service the advance unit itself. That involves cleaning and lubing the advance weight pivot posts. The first time I do one, I take the weights off so I can clean the posts up, then lightly grease them and re-assemble. Note - there is usually a thin little wave shim washer behind each weight on the post. Try not to lose those. For future servicing and lubing, after a ride while the motor is still hot, I apply a little foaming chain lube to the posts and springs. Nothing needs to come apart for this.
 
Greased advance, cut springs, advance now working perfect. Bike definitely accelerating and idling better than before. Go to rip down the street and no change. Still at 3000-3500 rpm major hesitation.

Back to checking the carbs i guess...unless anyone has any other ideas.
 
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