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cb750 carbs vs. cb900 carbs

ugly

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Ok. This is my first post here and from what I've read so far everybody seems really helpful. I own a custom 81 cb750k bobber that I've been building for the past 2 years. I'm finally down to just a few more parts to buy and paint it but I'm encountering my biggest issue yet, carbs! My carbs are shot. I've been looking online and at the motorcycle graveyards for a set but can't find a usable set yet. My question is, will carbs from a dohc cb900 fit my dohc cb750? Are they bigger around on the intake side, will my pods fit on them, is the cylinder spacing the same? I know someone here has to know. Thanks.
 
Not sure, I think they are the same spacing,etc. The best thing you can do though is save up some money and get some Keihin CR's. The stock carbs are absolute junk and you will fit the jetting on them forever. Yes they cost some money but stock carbs are not worth the frustration.
 
Thanks man. I just looked at the keihin CR carbs and those look nice as hell. Problem is I don't have that kind of money to drop on carbs right now. Might have to fiddle around with a set of stock carbs til I can afford those. But other than that are you sure I can use cb900 carbs. I'm just curious cause it gives me more options to search for.
 
for stock bike I would stick with the 750 carbs. I think they will swap but from what I have read the 900 carb is just a hair bigger and jet calibration is different. You would have to mess around with jetting them for the smaller 750, just another hassle that really sucks with those carbs.
 
I have all new rebuild kits and a jet kit for em. I have cut off open exhaust that's gunna get some washers in em for some back pressure. even when I had my stock set on it ran horrible. I don't mind fiddling with the Jets and needle settings. I'm also running pod filters on em too. I just need a set of carbs on it soon cause I'm I thing to ride this thing. It's been 2 years in the making and I'm soooooooo close I can feel it! Thanks for the info man.
 
If I remember correctly... and I think I do... the 750 and 900 carbs are the same, but the needles and jets are a different size. A couple of years ago I had I think 3 sets of carbs with different size needles and jets and was trying to figure out which were correct for my bike. All 3 sets came from 900's, but not all the insides were the same. I did post my general findings on a different site and if it's important to you I can probably find the information and post a link to it.
 
The 900 carbs are definitely bigger. And not by an 8th of an inch noticeable larger, the are wider so the carb mouths don’t line up with the boots by almost half an inch..I been trying to think of a way to make them fit, flex hose etc…I can also add a pic of me holding it up so you can see the difference, it’s huge
 
They are the same size..... One is a kehein v43 ....the other a 42........ I have rebuilt many the last ones we exchanged on a 1980 CB750 super sport intake boots and air box boots are exactly the same... The difference is internally.
 

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