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I apologize if this is a bit vague as I'm posting this while at work. I have been working on my 900 and am looking into possibly upgrading the intake at this point. I would like to either add a hyper charger or a cone filter intake. I am however worried about those messing with the amount of intake and fuel to air ratio. Not going for just looks. Any help is appreciated. I am still learning about the science behind the mechanics of it so bear with me.
 

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Morning,

My experience has been that anytime you change/modify the air intake or exhaust systems you will have to change the carb jetting. Not a difficult job, just have to experiment until you get the right combination of air/fuel mixture.

Don't be afraid to try different jet sizes, just be patient until you get it right because you will probably have to change the jets several time before you get right.

Keep us in the loop, Inquiring minds want to know!

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1982 honda 900 cb

I am having trouble getting the bike to run above idle. just rebuilt the carbs. Any idea what could be my problem?
Thanks Mr. bill


Also how do I post on the forum? instead of replying on someone else post.
 

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Also how do I post on the forum? instead of replying on someone else post.
"New thread" at the top and bottom of the first page listing of this forum (Vintage). Rebuilding 30 year old carburetors require a total strip down, 24hrs in carburetor dip (any rubber parts excluded) and O-ring and gasket replacement. Carburetor cleaner spray is useless unless you melt all the varnish and crud in the tiny passages and jets you can't see. Did you really rebuild them?
 

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Pale Rider
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If it has Constant Velocity (CV) Carbs, I would strongly recommend against changing the jets, the air box for pods, or any other changes. The CV Carbs require a balanced vacuum to work properly; if you put pod filters on them, you will never get them to work properly, no matter how you jet them. The CV's were designed very carefully, and they won't function without the OEM air box -- you can get close, but there will always be a flat spot you can't get rid of.

If you are hell-bent on using pods, I recommend changing out the carbs for something other than CV's. Another option, is to try to locate a fuel-injection system, but that is a very tall order, as well.

If you want to read about pods on CV Carbs, visit this site, http://www.cb750c.com/, and use the search function for "pod filters". There is plenty to read there. Cheers!
 

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Dynojet makes a stage 1-3 jet kit for your bike. They aren't as bad as some may think if your carburetors are in perfect shape, but not exactly a walk in the park. I hope you weren't going to change the pipes, they really work with the looks of the bike. That would automatically make any gains in power marginal unless they were swapped out for a quality 4-1 pipe. So that makes the change to pods a primarily a cosmetic change for a lot of expense and a fair amount of work. My bike came with a 4-1 pipe and the air box was damaged. With a stage-3 jet kit 4-1 pipes and pods I get 44MPG on regular pump gas, Idles perfectly and has a noticeable power gain. I would not have done it if the air box was useable and trying to dial it in with stock needles is a real PITA. Transition is much better with the Dynojet needles.
 
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