78 xs 400 E rebuild and modify

With a little brainstorming I came up with a solution to my taillight housing.

I reversed the rubber grommets to start. Then removed the socket from the metal housing. Drilled 2 holes through the rubber and 2 small holes in the raised portion of the taillight back plate. Then bent the tab on the socket, created a spacer from a blue bic pen, so I had something to tighten it down too.
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Added a nut to the back.
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Then added a ground wire to both those bolts.
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Drilled a hole in my taillight bracket and scored the sealing gasket to accommodate the wires for a tighter seal.
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Only had one functioning 1157 bulb but I tested both sockets and they both function properly.
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Engine is now back home.
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Also started dealing with the electrical.

The main harness rough installed. Need to shorten and replace quite a few connectors.
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The original headlight housing is to beat up for my liking. So using a after market I already had. I'll need to enlarge the hole and make an exit hole to get the wiring in and out of there to keep hidden.
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Also got new master cylinder. Original was toast.
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Changed the brake switch to spade connectors for it.

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Alot of these wire will be shortened quite a bit. I positioned the rectifier at the opening of the tray but I'll prbly take Chris's advice from earlier and relocate the rectifier to outside the tray, im thinking underneath.

This weekend I'm planning on making a fiberglass seat pan.
 
Well where was I... ha

World events and being an essential worker put a hamper on the bike.

Anyway... got some more parts in the mail. New brake lines, wire and plugs. New fork boots and fuel cap gasket.

Also made my seat pan this wknd.

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Used fiberglass and seems to be fairly sturdy. Just need to figuring out the mounting points.

I also went to see how the compression improved since the rebore but I got zero!!
What?!
I believe I forgot to put the LT on TDC for the cam timing.
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That pip mark and LT have to be at 12, correct? Would that cause zero compression?
 
Tyler Shiells said:
It has a 12.7mm bore which is a bit smaller the oem, which I think is 14mm? It will apparently be a bit stiffer because its smaller but will still work.
Click to expand...
Actually the smaller diameter makes it a lot more sensitive, the same amount of finger pressure exerts more force than the larger one. I have 11mm and it’s super sensitive
 
The zero compression turned out to be my guage. Forgot I took the Schrader valve out. Both cylinders are now over 150. The rebore was a success.

Took a month to get some parts in. But I got the new plugs caps and wires and a few rubber pieces from yamibits.

Got some foam rough cut to the shape Im after. Also going to use an old leather jacket for the upholstery. Which just so happens to line up pretty well on the existing seams.

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Onto the bike running. It fired up no problem but I couldn't sync the carbs. Turns out the damn pilot mix screws were both broken inside the body. Damn. I used my heat gun and they actually popped out fairly easy. But I do need new ones. Which are all on back order, which means with covid shipping times that 4 to 6 weeks wait. So I'll just buy a complet rebuild kit, cheaper anyway as the dealers want 30 bucks per screw.

I contacted SCI consolidated and they are out of the 78 carb rebuild kits but do have the 77s. As far as I can tell the only difference between the 77 and 78 was the main jet? Am i correct there? All other parts are listed as the same.
 
Manged to make some custom grips today.

I started of by removing the pocket from the leather jacket. Also used the divider foam that comes in tool sets. Cut them to size and glued them together.
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I then used the old handle bars in a vice so I could sit down, listen to some music and stitch away.
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I do not stich ever. And the few times I have I don't really remember and never leather.
Turned out well enough for my liking.
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And with that thin foam from the tool set, it actually is fairly squishy. Riding with engine vibs may prove that wrong but oh well.
On to the other one...
 
Rebuilt carbs this afternoon. Then warmed the bike up with a few laps around the property then about 5km down the road and back.

Then finally synced the carbs
20200817_171921.jpg

Main jet 137.5, Pilot 45, needle 3rd position and 3 1/2 turns on the pilot mix screw and seems to be running good.

Exhaust leak at the headers which is pretty loud under load. No one local has gaskets. Untill I fix that, not sure fine tuning will be worth it. Also dont think I'm a fan of these mufflers. Hmmm..
 
Ignition housing is junked.
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A previous owner, at one point decided to use a large metal screw to hold it together. Stripped and expanded the threads. Its toast.

So I rigged up a rocker switch I had lying around.
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It fit right into one of the holes on the headlamp brackets I'm using.

I'll have to order a new one. I think I'll be able to swap the key barrel out, to continue using the factory key.
 

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