Low915's Intro and Build 1979 Xs400

Low915

XS400 New Member
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On a whim decided to purchase one of these bikes knowing next to nothing about motorcycle mechanics or maintenance. Armed with this website and a few others I began to tackle this project not realizing the amount of frustrations and little victories it would bring. The bike was not running when purchased, but the previous owner assured me it was the previous season until the starter went out and he left it to sit in storage. Once in my possession I began to assess with the little knowledge I have what it would take to get this guy running.

First, I started with a new battery as the old one had cells almost completely drained. Success/failure#1- Motor and starter turn but bike will not hold an idle without throttle held wide open. At this point I found this lovely site and began to follow the steps that so many have followed before. The hope now is to get the bike running before the season ends then complete a full tear down repaint and replace anything necessary.

I then changed the oil and rebuilt the carbs with a carb kit using stock jetting sizes. I also reset the static timing following guides from previous threads. Success#2 the bike now runs on choke but dies the second the enricher is pushed in. I also replaced the tach cable which was snapped in half at purchase.
Next was tuning the carbs which with a lot of trial and error (including confusing the pilot jets with the mixture screws on which needed to be turned out) the bike now runs holds an idle albeit high and still dies when the enricher is pushed completely in. Which I suspect i need to reclean carbs and replace carb boots (in the mail as we speak)

Had a few other problems that i had to solve through trial and error but for brevity sake left out.

All in all I am excited to see how this bike turns out.
 

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Other issues that presented their ugly head is a rear master cylinder that wont hold a pressure which i think is due to a bad seal inside the piston assembly which will be eventually replaced by a brembo ps13 once I can find someone to help me weld new brackets.
-I also had to replace the rear tire and tube due to a leaky tube.
-I'll prob eventually have to rewire the bike due to previous owners poor sodering on wires they replaced here and there. Gonna hold off on this since the wiring seems to work without problems for now.
-Plan on replacing the oil filter bolt this week due to the head stripping the second i touched it.
 

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Also the starter at periods will turn but sounds like its not grabbing onto what ever it needs to and the engine will not turn. This is intermittent and the starter works perfectly about 75% of the time. Any idea what is causing this or what i can do to fix it?
 
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