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I will say, once again, my specific experience with a CB350 racebike with stock carbs is: Use the stock rubber velocity stack that comes in the stock air filter and clamp a foam uni-filter over the end of it. With that combination, I had to go 4 sizes larger on the main jet in order to get it to not run lean. I am assuming if I need to add that much extra fuel then I am making some additional HP. When I was first using that combination, I did not have large enough jets with me at the track and in order to race I had to remove the velocity stacks and run stock jets. I significant change. My belief is that the single best part of the stock airbox system on any bike with CV carbs is the transition at the bell mouth of the carb. Some (Emgo) pod filters sre designed so poorly that they actually cover some of the air passages that need to have full flow.

Ken
 

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Red/silver bike shown above does not have CV carbs on it.
 

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Didn't read the whole thread, but:

Keep that one the way it is.
There has to be a crapton of ratty, tatty 350's (or similar) for a few hundred bucks where you are.

Pick one up and have at it. Once you're done, you'll have two bikes, one a very nice unmolested, one as molested as you like.
 

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quote:Originally posted by kenessex

I will say, once again, my specific experience with a CB350 racebike with stock carbs is: Use the stock rubber velocity stack that comes in the stock air filter and clamp a foam uni-filter over the end of it. With that combination, I had to go 4 sizes larger on the main jet in order to get it to not run lean. I am assuming if I need to add that much extra fuel then I am making some additional HP. When I was first using that combination, I did not have large enough jets with me at the track and in order to race I had to remove the velocity stacks and run stock jets. I significant change. My belief is that the single best part of the stock airbox system on any bike with CV carbs is the transition at the bell mouth of the carb. Some (Emgo) pod filters sre designed so poorly that they actually cover some of the air passages that need to have full flow.

Ken
I poked around for a couple of minutes and found the perfect photos of the stock airbox and rubber intake to the carbs:

http://jeffrey.thedunsters.net/projects/mechanics/honda-cb-360-motorcycle/rebuilding-air-filter

Ken, it's not that I doubted you but the airbox boot was an aspect I'd never considered. Looking at the pic I can see what you mean. Given the amount of money Honda spends to engineer things, it makes sense they'd optimize the airflow for the best horsepower, or at least the best power curve. Considering how much vacuum is required to pull air thru a paper filter, swapping to pods would most likely allow more air into the carbs, but if that air is too turbulent...



Hmmm. These are on eBay for $40.
 
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