Carb replacements

Im looking for carbs that can be used in place of my current cabrs. I have a 1982 Spectre 750. Has the CV34 keihin carbs. I would like to find a set of carbs that are not vacuum operated. If possible does anyone know of a set of four os these i could use te stock trottle with and what model of bike they came off of so i could go to the motorcycle graveyard around me and find some. Thanks.

I *think* BS34's were the other carbs offered on the 750s.

May I ask why you want to ditch the 34's? Once I got mine squeeky clean they worked like a dream. Main things to watch out for is the dreaded diaphragms getting holes in them, the complicated pilot system being clean and those stupid polyster plugs shrinking and not sealing completely.

My fix for that was scouring craigslist and putting up an add for parts carbs. Guy had a set from a chopper project he almost gave me for $25. I don't think he knew the diaphragms get $50+ each sometimes.

Those three reasons are why. I i found 2 holes in diaphrams,polyester plug broke,and those pilot systems I've done everything to get them clean and still no luck. Are the bs34s vacuum operated?

CV34 I believe are the Keihin CV (Constant Velocity) carbs.
BS34 are the Mikuni CV (Constant Velocity) carbs, so they are the same type of carb.

I know diaphrams are expensive and no longer made. The local motor scrap yard said he'd sell me a good set of rebuildable ones for 100. Should i go check them out and see how the plugs and diaphrams are? Out of the BS and cv which ones are better

jon_570 wrote: ... and those pilot systems I've done everything to get them clean and still no luck....

Dis-assembly, cleaning with carb cleaner spray, sometimes gentle persuasion with a small wire, with resulting ability to spray throughout the pilot circuit into the carb bore, is usually a worthwhile objective.





Good Fortune!

If remove pilot screw #1 and spring #2, then block #4 and #5 orifices and #10 jet with fingers, and hold the #7 plug in position --- and spray into where the pilot screw normally fits, the spray should travel through the pilot circuit and exit out #6.

Ok ill go through these carbs one more time. I will use carb spray and i also have carb dip. I will completely dissasemble each carb and let it soak for 20 minutes. i will clean these one more time.

Patton wrote: If remove pilot screw #1 and spring #2, then block #4 and #5 orifices and #10 jet with fingers, and hold the #7 plug in position --- and spray into where the pilot screw normally fits, the spray should travel through the pilot circuit and exit out #6.

I will try this before dipping them. Thanks.

Please remember to wear eye protection when using the carb cleaner spray, because it always backfires toward your eyes.

Good Fortune!

Thats one of those things i had to learn the hard way lol

Patton wrote: Please remember to wear eye protection when using the carb cleaner spray, because it always backfires toward your eyes.

Good Fortune!

I can say that it hurts. Don't try it.