k91

Very nice!

Anybody know what size the pilot jets are on a 1980 XS400? I got it to run more consistently after replacing the faulty coil so I'm looking to place my order soon. Oh and the carbs don't have the movable clip on the needles its the 79 that does.

Cool project. Keep us updated.

New coil is on the way.

Nevermind I'm a dumba$$ ... figured it out a couple minutes later. 1980 has no points But I tested the coil and the secondary winding failed the test. So now I have to find a coil.

I think I figured out why my bike was running ok then not running at all. The left side is loosing spark. I tried to pull the points cover but the rear screw has some kind of plug in it? This is on a 1980 XS400. My other bike a 1979 has a screw in each hole. I tried picking around it to pop it out but it doesn't move. Its not rubber either. I guess I could try drilling a small hole and getting a screw in it to pop it out. Any ideas?

drewpy - You mean change the location of the clip? Do I move it towards the tip of the needle more or back towards the top of the diaphragm? I think now the clips are on the 3rd ring back from the tip of the needle. xs360 - The pods I bought say they are for 1980 XS400s but they were too small to fit over the carbs but fit perfectly on the intake tubes. So I didn't really gain any extra space. I think the mains are 132.5 stock right but what are the pilots? I was thinking about the Part #07-0041 taper tip mufflers from www.mikesxs.com to replace my blown out stock cans.

I was out on a test ride yesterday and the bike started bogging and barely kept running. I checked the plugs and they are both black which I figure makes sense since the airfilters have been soaked with fuel many times. So I pull the filters out and run again. Much better. But I check the plugs again and I'm lean of course. I have a set of pod filters to put on and I want to replace the stock mufflers. Any thoughts on how many sizes to go up? Maybe 2 sizes to start?

Thanks XS I'll try that tomorrow. In my haste I tried pushing the tips back up through with a screwdriver but only managed to break them off flush with the carb passage. I'll see what happens.

So I'm tearing down the carbs on my 79 and I notice the tips of the idle mixture screws stayed in the carb when I removed them. Well that explains why they never made any difference when it was running but now what do I do? I tried pressing on the tips from the inside to push them back out but that didn't help. Any ideas or am I stuck finding another set of carbs? Maybe I could just drill them out but I have no idea what size the hole is in the carb or if I have a bit that small.

Did the ball bearing in the clutch fall out maybe? Or you could try running through the adjustment procedure again.

Wow drewpy that silver bike is awesome Thanks for the pic.

I usually run at least 89 octane in my bikes since that has additives in it unlike the junk 87. I guess I'll order carb kits too since my old bowl gaskets are a little leaky anyways. Here's a pic of the beast when I brought it home if anybody is interested.

Thanks for your help guys Whats everybody running for oil as far as weight and brand? I bought some new carb holders last night so hopefully that cures my surging and racing at idle but if not its time to blow apart the carbs again.

I doubt I could be so lucky. Any ideas on the oil out the exhaust? Oh and has anybody ordered from that http://www.partsnmore.com/ place? They seem to have the best price on airfilters I've seen. Also the XS650 carb holders are the same as the 400 aren't they? Mikesxs.com has a set for the BS34 carbs but they are a different yamaha part number between the 400 and 650 but they sure look the same. Any idea?

It probably is the original. Now the mystery deepens again. Did another compression test this morning cold and it was 142 in left and 145 in right. So maybe I jumped the gun yesterday. I guess I'll have to do a leakdown now and see what happens. Maybe a valve is sticking when hot. And this was supposed to be a quickie project

To adjust the freeplay on the clutch lever you just adjust it at the lever itself. Loosen the bigger lock nut and turn the smaller one away from the lever until there is about 2-3mm of space between the lever and the lever holder. If you cannot get the lever to be within 2-3mm you need to adjust the clutch under the rubber cap on the left side of the bike(if you are sitting in the seat). Pop the cap off, loosen the 12mm nut and turn the screw until you feel some pressure then back off 1/4 turn and tighten the locknut. Now you should be able to make the adjustment at the lever. Hope that helps

Sorry to make this my first post but I'm feeling pretty bummed right now. I bought a second XS400 about a week ago in the hopes that it was nearer to seeing the road than my current project XS. Well I guess I was wrong again. It started, it ran, it seemed to drive around at least when I brought it home. Well I spent the last week cleaning, adjusting, and fixing what I saw. Today I changed the oil and filter, cleaned the screen, replaced the plugs and cleaned and lubed the clutch. Well now it doesn't pull itself in any gear but I can hear and feel it shifting. It also seems to leak oil from the left cylinder right at the exhaust?? I did a compression check and found about 100 PSI in the right and 92 in the left. I guess its time to put it on ebay for parts Any hope? I did drive it around yesterday and a couple other times too. I'm thinking the carbs were sticking and filling the engine with gas so now the rings are toasted since the oil I drained seemed to be mostly gas. But what is up with the clutch?