New xs400 problems.

A sudden lean condition could be an air leak. Like the plug on the unused vacuum port on the intake fell of.
Leo
 
I was mistaken, the sound is coming from the starter solenoid not the actual starter. Tried to start it earlier and I heard a loud snap somewhere around the starter area :banghead:. It still tries to start between the clicking though so I don't know whats going on.

Tried richening the mix and didnt really notice a difference. Sounded like I was getting some hiccups through the carbs. I pulled them off to clean them, maybe they just got some crud in them.
 
On the starter problem it could be several things. First thing low battery voltage, next dirty connections between the battery and startere relay, from the relay to starter. Bad ground side battery connections. Dirty contacts on the starter button.
If you take a large battery like from your car, hook jumper cables to it, negitive to frame, positive to a large screwdriver, touch the screwdriver to the cable to the starter on the relay, does this crank the starter? Is so you know the starter and connections to it are ok as well as the grounds on the starter.
Now with the key on unhook the blue/white wire on the relay and jumper it to ground, this bypasses the start button and should crank the starter.
If it does then the push button or wiring between the relay and button need work.
That's the testing, but it sounds like your relay is shorting out. If so it needs replacing.
On the carbs, yes it doesn't take much the plug the passages in the carb. So a good cleaning is a good first step.
Leo
 
Guess I didn't turn them out enough, went from 2 turns out to 4 and its not backfiring anymore but still bucking a bit. It seems my carb boots had come loose as well, didn't notice until I had already cleaned the carbs and was putting them back on. Doesn't look like that had anything to do with it but good to know in the future to check them every now and then.

As for the starter issue, I swapped in a new solenoid and its still acting up. Its not even really trying to turn anymore just a bunch of clicking. Is there anyway I could have put the cover back on wrong when I re-wired everything? I hear some rattling down there somewhere :(.

Edit: Damn, I hadn't even thought of the battery since I just went through all that stuff to get it charging. I swear my mind has been lost somewhere lately. Sure enough I just checked the volts and they are low. I guess its still not charging correctly.

To answer your question I tried jumping the terminals earlier on the relay and it turned over pretty sluggishly one time and that was it. I haven't tried the car battery yet or unhooking the blue/white wire. I've got the bike on the charger right now since it was below 12v.
 
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Ended up being a bad battery, I suspected as much but couldn't afford to replace it until now. Heres some issues im still having (the list seems to be getting longer every week :().

Im still getting a bucking, richened the mixture to 2.5 turns out. My plugs tell me im running really rich since they are completely black so I doubt turning them out more will solve it. I haven't messed with the needles yet but should i try raising them? I can't even remember If I have the adjustable clips or not.

My clutch has always been a bit funny, when I got the bike the lever adjuster was backed out almost all the way. Even after adjusting it at the case I still can't turn it in much without making the clutch completely useless. As of right now my clutch only engages like the last 10% of the lever right before you release it, the rest of the pull (what little there is does nothing). Since I have clubmans I tried shortening the cable which seemed to help give me more of a normal feeling pull but it still only engages right near the end. I've got a new cable on order to see if that changes anything.

I've got blobs of grease showing up behind my clutch cover on things, its pretty thick stuff. It's obvious that the chain is slinging it around as I also have it up the back of a couple of my shirts as well. This one isn't as much a big deal just means I will have to clean behind there more often just wondering if its normal. I saw some that looked to be silver too, kinda weird.
 
No, it's not normal, either you have an oil leak or using to much chain lube.
Clean it very well. Ride it a few miles and check for a leak, it may take a few tries to find it but once you find the leak you will know what to fix.
Most probably a bad clutch push rod seal or the seal behind the front sprocket.
Leo
 
Im still getting a bucking, richened the mixture to 2.5 turns out. My plugs tell me im running really rich since they are completely black so I doubt turning them out more will solve it. I haven't messed with the needles yet but should i try raising them? I can't even remember If I have the adjustable clips or not.

try a bigger mains, I think the pilot is big enough

My clutch has always been a bit funny

you don't say, only the other day my clutch said

"Man: This is the 4th time this year i have had to change the clutch.

Woman: Dont look at me, i dont use it."

I also have it up the back of a couple of my shirts as well.

no comment :D

This one isn't as much a big deal just means I will have to clean behind there more often just wondering if its normal. I saw some that looked to be silver too, kinda weird.

yep, if you have no chain guard on, the chain grease will fling. I clean mine with wd40 first then grease and wipe off the excess and leave to dry overnight.
 
Well its not an over-lube problem, I haven't even lubed it yet since I put it on. If it is an oil leak I would guess behind the sprocket since i've already replaced the push rod seal. I wouldn't have guessed oil though since it's so thick but I will clean everything and keep an eye on it.

I ordered a new tach cable too so I should be able to finish fine tuning this thing. I will try bigger mains.

As for the clutch, I know you never really can tell until you tear it down but I was looking at the xs400 section on Mikes and im kinda confused. All I need are the friction plates/springs?
 
Some of my parts came in this weekend so I decided to work on the bike a bit. I cleaned the chain like I used to with my sportbikes, de-greased with simple green and a brush and then lubed it with some chain lube. Now my chain is flinging red stuff from the o-rings. What gives? I figured cleaning it would help and it seems to have done the opposite.
 

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Looks like the chain flash rusted from the cleaning. I have gone to nickel plated ones on both my bikes because they will not rust.
 
Ya, thats possible. The chain wasn't new or anything to begin with but it sure didn't look like this. I've always used simple green to clean them so I didn't really think anything of it. That probably wasn't the cause but I read the manual and went to get some kerosene anyways. Im going to re-clean it and use some other lube.

The lube I used was this clear chain guard stuff from the local yamaha shop. The guy told me thats what they sold the most of. It comes out like a foam and turns into a sticky mess, I figured it would dry over the weekend but you can still touch the chain and it will come off on your finger, kinda like syrup.
 
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Finally got my tach cable in and all hooked up. Now I've been real easy on this bike since I got it running, pretty much shift to 6th and cruise. I was always under the assumption that I was running it pretty high up in the rpms. I've come to find out that's not the case. So far I have only been able to get it up to 4k rpms and it sounds/feels like the engine is screaming at that point. I can't remember which of my xs400's I pulled it off of but the tach shows redline at 9k. Im pretty sure at the point that the bike wouldn't even hit that if I tried. Im stumped, could it just be my imagination because of the open exhaust? Or something worse?
 
I got around to really working on the bike today. Checked valves, the left side had to be adjusted but the right was ok. I also put the new battery in, rode it around the block and I can feel a huge difference. It revs up alot easier, still haven't really taken it too much higher than 4k. I figured the old dead battery was causing the tci not to be able to work well and that might have been part of it but maybe my mains might not be big enough still.

I attempted to sync the carbs again using the homemade manometer. I can get it even for a second or 2 but then one of the sides starts pulling it. I've checked for air leaks and everything seems to be pretty sealed up.

What is the point of the double wall exhaust? Is it necessary? Im pretty sure when I re-routed the left side over to the right I must not have welded the inner pipe back because its rattling like hell inside there. Can I just go back in and remove it?

Heres a couple recent pics. After messing with the exhaust a few times this is how it ended up.

Edit: My tach needle broke today, in the exact same spot as the spare one I have (not suprised). The only thing I can think of is it happened when I took the bike off the center stand. Is there anyway to repair this?
 

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Re-routed the exhaust for the last time I think, scrambler style. This seems to have fixed alot of the issues I was having. I've seen others do this as well, anyone find a creative and somewhat cheap way to make a heat shield? I do plan on wrapping them at some point but since that will be a new task for me I may end up still wanting some kind of guard right where my leg is.
 
My bigger mains came in, threw in the #150 and it didn't really change anything. I also tried to add a couple washers under the needle to see if that would help but it didn't solve the bucking issue either. The bike did seem to run better in the midrange but struggled from a stop until i gave it gas like it was gurgling and would do it if I let off the throttle. At that point I thought maybe the #50 pilot/needle position was causing it to be too rich so I dropped down the pilot but then it started backfiring on decel but still bucking.

I figured maybe something got through the filter so I took the carbs apart to clean. In looking at the diagrams I can't figure what this hole goes to. What is its purpose? Something tried to come out during boiling and I noticed the holes on both carbs are seriously clogged. Dug out the thick layer of green stuff in it until I hit the brass piece down in there.
 

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