carb interchange...

CDNTX650

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I know it's been asked...but i forget. If i get the right rubber intake manifolds, can i run 80 and up carbs on my 74? (i know they arent as good, but i plan to get a set of xsjohns needles if i find some.)
 
Yes you can. The TX650A used the 447 engine, and the intake flange angle in the head is identical to the late engines. There are no fitment problems.
 
How about the other way around...? I have a 1981 Special with the bs38's (pretty sure that's what they call em) and read somewhere that the bs34's were a bit better? Swap?
 
They started using the bs34's in 80. Your 81 has the bs34's. The easy way to tell is the carb top. THe bs38's have a cast allpy top, the bs34's have a chrome steel top.
 
The only thing you have to change is the intake flange/header. Both 38 and 34 intake flanges will fit the engine, i believe.

Are your current carbs single throttle wire or dual? The flanges are different for the 38's, but if you're going to 34's, you have to change it anyway, so no big deal.

And the 38 vs 34 thing... They each have their pluses and minuses. Both can be tuned to whatever application you're running easily.
 
the bike is missing the throttle sleeve and cables. It is a 74TX that is like 95% there. So i'll use what i can. My pod filters worked well on my 77 so i'll probably do the same.

This bike will be an almost stock, but a few bits are different. Motor has 9000 miles on it. Owner plugged everything up. Spun over nice and seemed to have good compression on both cylinders. Stator/Rotor check out:thumbsup: (been lucky on both of mine) Even has stock exhaust....one muffler is rusted on though. Had to order new forks...chrome was a disaster on the old ones.

I hard tailed my last one and hated myself for it. Then i rebuilt a 73cb500/4....man the soul of the xs just wasn't there (i can never ride an inline 4) so i sold it too. Found this XS for free on local craigs list so me and the wife went and picked er up.:bike:

I am a Ducati and XS guy for life.
 
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