Any suggestions for new bike build?

IMG_1340.jpegIMG_6727.jpegVee mine started out much worse than yours and she was a calendar girl this year…
 
I used 36cal lead shot. I was worried about sparks, didn't have time to let it dry all the way out. Shook it like a maraca.
Dump blow out repeat. It worked well. I will do that again then try the vinegar trick to finish off the finer rust.
 
Carbs are pulled. Preparing to disassemble tomorrow. Before I do I have a few questions/concerns.
First concern; While working the carbs out of the intake manifolds the two carbs separated. There is a rubber tube containing brass connectors that is the bridge between the two. As you can see by the picture when connected they are staggered. What's going on here? When I was working on my BS34s on my '79 they seemed to be connected in a couple different ways and pretty symmetrical(not staggered like these 38s).
Second Concern; Both carbs seem to have had an elbow on the float bowl that is there for a breather hose but both cracked off at the elbow? One was already broke off and then I seemed to have broke the other whilst wrestling to get them off the boots. Is this going to be an issue?
 

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Those lines shouldn’t be staggered. They will be joined pretty much the same way your BS34’s were the fittings on the early models were an issue. I believe there is a thread here about that, possibly in tech?.
 
Carbs disassembled and soaking at the moment. Upon inspection one of the diaphragms had a hairline tear. I'm sure you guys are familiar with Mr. Miyagi on YouTube (another xs650 enthusiast). He uses a 3M weather stripping product right around minute 48 in this video.
Anyone have luck with this fix? Also thanks again to mailman, winged and GLJ for the pictures provided. Helped me wrap my head around what I was working on.
 

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He uses a 3M weather stripping product right around minute 48 in this video.
Anyone have luck with this fix?
I use fuel/oil resistant RTV from the auto parts store.
 
Carbs cleaned up to the best of my ability. 40 years of sitting didn't do them any favors. The insides were stained black for the most part. Wasn't able to remove the black stains from the slides as you can tell from the picture. Overall, everything cleaned up nicely. The RTV worked well on repairing the split diaphragm. Did the practice test on both by lifting slide and covering hole with thumbs. Both checkout. Cleaned out all of the air filter components and made some custom high density foam replacement. New oil. Crafted some auxiliary gas tanks to feed both carbs(gas tank is currently full of vinegar and drywall screws). New battery charged and ready to go.
Am I ready to try and start this thing? Theoretically speaking, do I need the battery to bring the engine to life if I'm kicking? Or is that just to power electronics?
 

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You will a battery good enough to keep the voltage up to 11+ with the ignition on, 12+ is better. RTV may work fine for awhile on the diaphragms but eventually you will need to get new ones.
 
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Theoretically speaking, do I need the battery to bring the engine to life if I'm kicking? Or is that just to power electronics?
Yes, you need the battery. Ignition is run off of 12v power. The alternator doesn't work (supply power) until it, itself gets 12v to energize the rotor.
Everything runs off the battery on startup.
 
So put the battery in and got lights all over. The starter works and is trying to start the bike but it wouldn't turn over. Basically drained the brand new battery trying to get it to turn over. Charged the battery to full again and from there tested the spark plugs and spark plug caps by grounding them to the engine and doing the screwdriver trick. Both seemed to be getting no spark at all. What would you guys do from here? All the lights and starter are working and hadn't failed over a 40 year sitting period. Would both coils fail sitting that long?
 

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When you say the starter is trying to start the bike do you mean it’s spinning it fast enough or it’s trying to start? Have more than 12v at the coils and have you done a resistance check on your coils? If no ignition start at the switch and work your way through the ignition circuit.
 
The starter could be drawing too much current. My E-start will not start my SK bike cold. SH bike fires immediately from E-start, hot or cold. I just had the starter apart and cleaned it up, particularly the commutator. I have yet to reinstall it. I’m just sharing my route on the problem. The SK bike starts first kick when cold.
 
When you say the starter is trying to start the bike do you mean it’s spinning it fast enough or it’s trying to start? Have more than 12v at the coils and have you done a resistance check on your coils? If no ignition start at the switch and work your way through the ignition circuit.
I hold the start button, it's operating, and the pistons are going up and down. So I'm a novice with a multimeter and most things electronics. Will try my best and report back. Is there a 1975 wiring diagram in the tech section?
 
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