77 xs400 starting problems

Yeah captchrome I was thinking about shimming it up first to see if that starts to produce some results. Ive got some shims of various thicknesses that I am gonna play around with today. The needle im running is the y264 that I came across on this forum, was told this was a very close approximation to the 5z1. The picture is from xs650.com user 5twins. 1000013388.jpg
I believe it is a little longer than the y265. Middle clip position with 132.5 main and pods on the hpipe has given me the best performance so far.

Tstidham, I thought about this as well. Don't really know how I could test the tach, I've got the idle set at 1200 and the tach holds steady there, when I hit it with the strobe the timing marks line up and it advances like it should. My only thought is that maybe the dash is from a different xs with a different gear ratio on the tach. There are pics of the dash on the first page of this thread if you wanna look. All I can say for sure is that when I ride it on the country roads it loves to cruise at 3k which seems pretty normal to me.
Maybe describing it as screaming at 4k isn't accurate. It sounds like its spooling up when I start to get up there and it feels like it wants to give more. I know these short stroke motors are designed for the high rpms but I'm a novice to bikes and wanted to get some other opinions on it before I blow the motor up. I get it, its hard to really diagnose a problem like that through text but I thought I'd throw it out there anyways.
 
When setting clearance for your valves with feeler gauges, how do you determine the correct fit? Should there be absolutely no way to get a .006 feeler gauge in there? Should it be kinda difficult to get it in there? In the machine world .001 is .001 so nothing over the tolerance should fit period. What do yall look for?
 
Alright cool thats how I've been doing it.

Been working on sealing an exhaust leak. I know there's a crush washer in there but this one has a spacer of some kind on it.left side looks toast. Anybody seen anything like that before?
 

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There are two types of exhaust manifold gaskets I have seen. One is the spiral wound type that you have in your pictures. The other is a copper crush washer type (it looks like a big copper ring). Either works and both get deformed once they are tightened up between the head and the manifold and must be replaced as they are one time use parts.

When installing these gaskets, make sure that they stay in the head securely when you are installing the manifold. If the gasket is loose, use some grease on the face to keep it stuck in position. The grease will burn off and smoke on start up, but at least you will get the proper seal. It looks like your left one moved during install.
 
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