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Push-Pull Throttle Cable

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mgy66:
Thanks John, that really helps. I did try to loosen the lock nuts and turn the adjuster nuts so that the rods disappear inside the nuts. As per my previous post, the prob is that the tips of the rods just flush with the lock nuts surface. I feel when turning further that I have reached a hard point, maybe the needle with the main jets?

What I am thinking is the guy that put the carbs together may have attached the needle to the sliders at the botom of the rims.

From your experience, do you think I would need to take out all carbs and dismantle them to check what is the position of the needles wrt the sliders? If the assemblies (sliders + needles) are too short could that explains why despite having the rods and lock nuts flushed I still have a high rev.

What do you think?
Thanks,
Mark

neat street:
Hi, I am not experienced in big bore kits. or jetting them, but the needle clip would normally be in the middle, and the jets you have are for a standard set-up. if the needle is lower, you would get more air to fuel ratio, if higher, then more fuel to air ratio, but could affect the speed as well? it maybe worth stripping the carbs to make sure all is clean and you have the correct jets for your set-up? (different makes of jet come up to different sizes) Ashimoto or one of the other more knowledgeable guys would be of better assistance here I think, but try that first, it wont hurt.
best wishes
John

mgy66:
Thanks,

I take it that I would need to strip out the carbs from the engine to access the needle clips inside the carbs... That is not good news as I am too comfortable with the whole procedure of disconnecting and dismantling all the pipes, cables and supports.

I will go with your first suggestion to balance the carbs and play with the adjuster nuts. I have actually tested to screw the rods upwawrd instead of downward and it seems it have a better result. The idle screw seems to be slowing down the idle and when I turn the throttle handle beyound the idle point I can hear the rev slowing down almost to stalling.

There must be something with this throttle return cable acting on closing the sliders without acting on the needles. It is worth noticing that though there is a idle screw to adjust the position of the carb lever but there is no screw to adjust the return cable manifold.

As you pointed out pushing up the throttle assemblies increases the richness of the fuel to air ratio. It may be that the effect is actually to reduce the idle and/or to allow the idle screw to play on a larger range of idle rev.

I will test further offsets between the adjuster screws and the tips of the rods and will post the effect on the idle speed.
Best,
Mark

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