MmmBoost's '78 XS400 Cafe Project

I seriously can't believe how hard of a time I had today trying to find new inner tubes for my bike. Apparently 18" wheels are just an oddball size. The first shop didn't even stock 18" tubes for anything. Only 17 or 19. At the next shop after 10 minutes of the parts girl digging in the back she comes back with a torn up back and an inner tube that's so old the label has turned yellow and the rubber is all crusty and hard. No thank you... and I quote, "Yeah but it's cheap!" The only other one she has in stock was a heavy duty dirtbike one that weighed like 2 lbs and cost $35. No thank you. I guess I'll just check the old tubes for holes and re-use them.

#IwishIhadtubelessrims
 
That's sad. The one I go to just does yamaha and is a small family owned shop that has been there since 1972.
 
Man I wish. I just checked the size on the old rear inner tube and it's not even the right size. I honestly don't know how the previous owner managed to half-ass so many things on this bike. 3.25-3.50 inner tube in the rear when he was running a 4.00x18 tire. I'm putting on a 110 now which is slightly wider.....so it looks like I'm back on the hunt for some inner tubes. No idea what's inside the front tire yet as I haven't dismounted it yet.
 
110mm/25.4 = 4.33"

So are you saying a 3.25/3.50-18 tube would work in this tire?? Other than mountain bikes this is the first vehicle I've ever owned that has a tube in it. I mean I know 3.50x18 was stock.... The PO had a 4.00x18 on with this dinky tube in it.
 
So funny story...(just when I didn't think it could get funnier) I decided to peel off the front tire and see what tube was in there. On the stock 90/90 they had a 3.50/4.00 tube stuffed in there. :umm: So the shop that put the last set of tires on fucked up and swapped tubes. So I guess it's all good now.... I've already put the rear tire back on with the 3.5/4 tube.
 
Started to clean all the oxidation off the engine case. I still haven't decided if I'm going to paint the case or not.
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What processes or cleaners did you use to do this?
 
What processes or cleaners did you use to do this?

For degreasing the engine, lacquer thinner is about as good as you can get, but it's pretty nasty stuff.

For getting rid of the oxidation.... Elbow grease and a lot of it. What I've found is working the best so far is grey scotchbrite pads and WD40. It seems to help lubricate the pad enough to clean up the surface but not leave scratches in the surface. Around the bolts and in the bolt heads I've been using a small brass cupped brush from my dremel set lubricated with WD as well. I just picked up some pipe cleaning brushes today to help clean up between the fins.
 
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Finally got the new rubber mounted!
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And then I gave the wheels/tires a bath before hitting them with some plastidip (I didn't want to paint them permanently just yet)
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I also did a little frame-trimming
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I have to sort out a rear hoop, but it's starting to look like a cafe
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Wheels painted black with a Rustoleum rubberized coating. Similar to plastidip but it's half the price and it doesn't seem to be as rubbery and sticky as PD
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Nice satin finish
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took off all the brittle and aged sheathing from the stator/field coil harnesses and replaced them with fresh heat shrink
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Also start to make a die to bend the tubing for my frame hoop
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Perfect
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I took a piece of frame and sharpened it, then welded it to a chunk of round bar so I cold carve out the die to fit the tubing.
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Cutter in action. I had to stop and resharpen in quite often since the material was just mild steel and not HSS like normal lathe tooling.
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No pipe bender.......no problem
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This actually worked better than I expected.
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A thing of beauty. Now to trim it and fit it up to the frame
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I turned some plugs to help with the alignment/fitup of the frame hoop onto the existing frame.
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Plugs installed
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Fit-up and tacked for the time being.
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Thanks Jeff!

It's amazing how much different it looks from when I started out. Black wheels, some new rubber, and a new seat really transformed it. Mocking it up has definitely motivated me to hurry up and get this thing back together so I can ride it :)
 
I've been spinning my heels a little with the bike. There are a few things that needed reworking and I was kind of procrastinating like a pro......but I've finally started to make some progress again.

Fitted the stock 12.5" shocks in and there's only an inch of clearance to the frame hoop, so that's going to have to get fixed.
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I love my western facing garage. amazing light in the evenings.
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I turned some 1.5" shock extensions to give me 14" long shocks. They thread into the existing rod end with a stud and then the rod screws into the extension.
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Started turning the foot pegs for my rearsets I designed.
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Clipons and mirrors finally showed up!!!
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She's coming together. I had to toss in the motor to check for chain clearances with the new 14" long shocks.
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Just to let you know from experience-
With the rear jacked that high, and the front that low on the tubes, you will have a horrible handling bike. It will have very nervous/twitchy turning characteristics. The bike will also have poor straight line stability at higher speed. Be ready for death wobbles with any bumps while at speed. Even with a steering damper I was still getting shakes, and that was with my front higher than what yours is set at and with better forks. Lowering the rear down a bit fixed my issues completely. I didn't get much more time with it after fixing the problem before it was totaled, but I'm confident the issue was taken care of.

Basically, raise the front to where it should be, and try to get away with lowering the rear back down a bit more. Trust me.

Best thing to do is fabricate the rear/underseat for clearance instead of trying to use longer shocks.
 
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