Fuel inlet?

lumbee

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Is this the right place where fuel should come into these carbs? I've seen some pics of these carbs where there is an elbow here, is that what I need?
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Being threaded, I'd say yes. Not an expert, but those look to be BS34's from a European XS. They used a banjo fitting (on each carb I think) for fuel delivery.
 
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Those don't look like 650 carbs. Similar, yes, but not quite the same. They look pretty rough as well. Before doing anything with them, I'd have a look inside the float bowls to see if they can even be saved.

But yes, that's where a fuel line would connect. You'd need to add a threaded nipple or elbow. There would have to be a way to feed the other carb as well, either a similar threaded hole on it or a crossover hose between the 2 carbs. 650 carbs have a "T" fitting between them that feeds both carbs .....

34 Alloy Tops2.jpg
 
I believe the BS34's, as well as BS38's, were used by multiple mfrs and there were differences in specification. Not all BS34's and not all BS38's are alike in certain details.
Pilot jets on BS38s are an example. Some years use different jets than other years.
 
They look pretty rough as well. Before doing anything with them, I'd have a look inside the float bowls to see if they can even be saved.
Watch yo mouth! :p They've been soaked, cleaned and reassembled. I know they look a bit grungy but they should be mechanically sound at this point (fingers crossed)

The opposing carb has a hole in the same spot, but its not threaded. I was thinking that the fuel would feed in from this carb and flow through the crossover in the middle to the other.

I'll snap a pic inside the bowl so ya'll can see whats lurking beneath.
 
Lol, no offense. Just noticed the floats look a little rough.

If I could make a suggestion... I'd recommend replacing all the jets.
1) New jets better than cleaned jets.
2)You'll likely need to do some jetting to get things dialed in, so you'll need a selection anyway
3) They are fairly cheap in the scheme of things
 
It appears one man's idea of a clean carb differs widely from an other's, lol. I don't think those are 650 carbs, the spacing looks off (too close together). Also, I've never seen any that connect the throttle cable in the middle like that, it's always on the outside of the left carb.
 
I don't think those are 650 carbs, the spacing looks off (too close together). Also, I've never seen any that connect the throttle cable in the middle like that, it's always on the outside of the left carb.
You may be right. KZ750? I did one of those a couple of years ago and am starting to wonder if I didn't put these carbs on the wrong shelf.
 
Nonsense. Never seen one I couldn't bring back to spec.
OK but for $2-4 I'd just as soon start with new. Especially when it's very common to need several sizes to get things dialed in just right.
Instead of spending time cleaning the old ones only to find out I need smaller or larger, I'll just order a couple of each size a few above, a few below the starting size.
If the bike was running right before and no changes have been made then, sure clean and reuse.
 
I have encountered bad jets. If they were sitting a long time covered with fuel varnish, that stuff can actually eat away the brass, making the metering orifice larger. But, there's no telling what size it corresponds to now. I just replace them. New genuine Mikuni jets aren't that expensive and I usually need different sizes anyway because I've modded the bike.
 
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