New owner with no idea where my bike problems are stemming from

myleskilloneous

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I purchased a 1980 xs400g a few weeks back and I just can't get it up and running for more than a day at a time with no problems. I'm about to call it quits and sell it if I can't get it running soon because it's becoming a bit too pricey and time consuming trying to just get her out the driveway. I'm losing my job soon and was planning on taking this motorcycle camping around the state until school starts but I don't even feel comfortable driving it down the street.

Initially, it wouldn't turn over and the choke was stuck "in". I purchased a new battery and sprayed some carb cleaner into the air intakes and put some seafoam in the gas and oil. After dropping in the new battery it fired up nicely and I was able to take her out around the block a few times. Whenever I pulled the choke out (with pliers) however, it would die out immediately. Weird, looks like I'll just leave the choke "in" all the time.

TRANSMISSION
When I tried taking her around my block, I realized the transmission was having issues. It had no problem going to first but I could NOT get her to second or above. It wouldn't even move past neutral. A friend and I seemed to think the problem was that the shifting lever was physically hitting the part of the engine directly above it. He insisted the lever was bent a little from when we first picked up the bike (he drove it home for me, NO issues) so we loosened the lever a bit and I was able to wiggle it a few mm's "away" from the bike. Miraculously, this (or some fiddling with it at least) seemed to do the trick and the bike was able to shift through all the gears relatively easy. I've been able to take the bike out a bit further from home and go through more gears and I feel comfortable with it about 80% of the time. Sometimes when I come to a red light, put it in neutral, and release the clutch, the bike jumps forward as if it's still in gear and stalls out. Not cool, especially because getting it started can be such a pain sometimes. I've also had it act up and get "stuck" in 1st/neutral again without being able to go back to second which is scary when I'm in traffic and unable to accelerate. There's also been times I'm shifting through lower gears and the bike suddenly displays neutral but I am clearly in gear because I can give it throttle and accelerate. I always have to pull over and go through the lower gears over and over until the bike seems to "reset' or remember where it actually is.

I was pretty happy with the way she was riding the other day and took her out for an hour before and after work. Started right up when I needed her too, shifted through no problem (only a few minor issues getting stuck in gear sometimes or unable to shift out of neutral), and I was really happy when I got home that night. I put her in the garage and went to bed.

Came out the next morning and again, the engine wont turn over. I try kickstarting her a few times (shes never been able to start by kickstart alone, but it seems to help "warm her up"). She's alllllmost there every time but doesn't seem to have what it needs to turn over that first time and get going. I put her on the trickle charger for a few hours and she seems to have a bit more energy but still has trouble getting started. I get her started a few times and by adjusting the throttle adjustment am able to idle her around 1500 to warm her up.

This morning, after not working on or riding her all day yesterday, she again didn't have enough juice to turn over and get started. Tried kicking it for a little and it was almost there again with both kickstart and battery but unable to get started. Put her on the tricklecharger, came out and with a little move and luck and praying got it started again. I decided to use some carb cleaner again and spray it in there while she was running. The first time made her die out so I stared it again and was able to get some in there while it was running and I put her into 1st and 2nd on the center stand.

I went back to my stuck choke which is bothering me and hit it with some more WD40 in attempts to free it up a bit. I grabbed my pliers and was able to pull it out a few centimeters at which point the bike started revving up to 5,000 and going crazy. I quickly jumped up and hit the kill switch and the bike backfired loudly.

I have no idea what I'm doing and although I love the bike its becoming a bit much to try to get this running to where i am comfortable riding her. I get my license this weekend and wanted to take her out for a 4 day trip next weekend but don't want to get stranded when it won't start in the middle of nowhere.

Is there anything else I could be doing at home to help diagnose the problem or find a solution? This weekend I will try giving her an oil change myself which may flush out any shit in the engine that is still sitting there. Is there anything I can do while I am changing the oil to help the engine out?

Also, what could be the reason the kickstarter won't work as well? It would be nice to have this as a backup when the electrical ignition doesn't seem to be doing the trick.

Hope I don't sound like too big of an idiot. I really do love this bike, but my recent loss of employment and knowing what it might take just to get it running is making me lose a bit of hope in riding her this summer :banghead:
 
I will also be borrowing a friends voltometer this weekend to test the charging system. WIllem suggested that when I was initially having issued before I purchased the battery. It's still odd that after a trickle charge it still wont turn over right away, making me think it's more mechanical than electrical.
 
I also advise clutch adjustment. check if your spark is strong, if not start with the cheap things then ie. spark plugs, plug caps, oil, coils and lead wires
 
Your choke is working. With you pushing the choke "button" in, that turns the choke off. Pulling it out will turn choke on.

I also agree with the clutch cable adjustment. That will probably fix your shifting problem. Unless the cable is bad. When you pull the clutch lever, does it pull smooth?

Also Dont be discouraged. Dont look at the problems as a whole. Pick one thing then fix it. You may find that these problems are easy fixes.

Search the site and download the service manuals for the bikes.
 
The way you talk it sounds like your young an have little experience with bikes. If so you have a lot of learning to do.
Getting a 34 year old bike and expecting it to run like a new one is a bit foolish. In those 34 years was it kept in a heated garage with a good maintenance regiment? I doubt it.
Your bike needs a lot of TLC to come back from the dead.
As mentioned cleaning the carbs is step one. I'm more experienced with the XS650 but they used very similar carbs, we XS650 fans think of this, www.amckayltd.com/carbguide.pdf as our carb bible. It covers the BS34 carbs. Readit, print it out read it. Use it to tear down clean, inspect your carbs, Once you have inspected them you can buy any parts you need, DON'T buy carb kits, they seldom have all the right parts. Buying the parts you need like gaskets are cheaper than kits.
I would also recommend starting at one end of the bike and inspecting the wiring. Pull apart every connector, clean the connections. They can be tightened if loose. Work your way to the other end. This will fix most of your electrical problems before you have them.
Don't get discouraged. Your bike is a good bike and want's to be better. All you need is to listen to what it tells you and fix things that are wrong. It can be fun to fix things, and it really feels good when you do something right and fix the problem.
We all have been where your at now.
We all support you.
Leo
 
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So I came home from work and put new spark plugs in one night and it fired up like never before and had LOTS of power. I've never seen it pickup like this in 1st/2nd gear and was able to get it on the highway for the first time...Easy shifted through 4th 5th 6th and was cruising at about 70 for a mile or so when it slowly started to lose power. Shifted down into lower gears but it was obvious the bike was bogging down. By the time I was on the exit ramp it just completely shut off. I was able to get it started enough to get down the block into a residential area but the battery eventually lost all charge and I had to push it home about a mile and a half (most of it uphill...fuck)

Put it on the trickle charger when i got home and took a look at the fuse box the next day. The two clips that hold the main 20A fuse had a broken portion on one side so the fuse wasn't making contact properly. I ended up just cutting the wiring for this fuse out and replaced it with an in-line fuse holder for the main 20A fuse. I also decided to completely drain all the oil as I think there may have been too much in there to begin with. I thought my sight glass was dirty but I think it was just wayyy overfilled (this may explain it bogging down, especially losing power and bogging down uphill if the oil was flooding the carbs or something).

So, the oil drain plug on the bottom of my engine is super stuck and looks a little stripped from the previous owner (and myself) trying to get it off. I was able to use the plug on the left side of the engine to get some of the oil out and eventually loosened the 4 hex bolts on the L "Yamaha" cover (crank case cover?) which let a lot more oil bleed out. I left it like this while I was at work and came home to a very full drip pan of dirty oil. I put in a few quarts of new oil and took her around the block. Again, things were off to a nice start but after a few laps, especially the uphill portion, it bogged down again and lost electrical power. Seemed the battery was completely dead.

I think the bike definitely has some slight mechanical issues but they get hard to diagnose with the battery losing power so much. I bought a voltometer today on my way to work and am going to check the charge when I get home and after I idle it for a bit. If I feel safe enough getting her on the street I'll take her around the block some more and check the charge again to see if the charging system is working.

I think this will be my new focus since it'll be hard to address mechanical issues if the bike wont run long enough to diagnose them.

If it is something in my charging system, what parts would I go about replacing? My tank ended up empty today after running her for a bit so I'm going to use this opportunity to take the tank off and give the wiring a closer look from headlight to tail. it fires up nice when it's fully charged and warmed up a bit but i'm still not confident on the battery holding enough to take her out for a few hours or so.

Appreciate the constant help. I found a nice shop close to home where the owners first bike was an xs650 so I may drop it off with him for a few hours if I hit a dead end with this.
 
Sorry left of the last part on the link to the carb guide. Went back and fixed it.
On your charging system, Once you charge the battery, start the bike. Check battery voltage at idle, at 2000 rpms and 5000 rpms. At idle it will be around 12-13 volts. At 2000 rpms it should rise up to around 14 -14.5 volts. At 5000 rpms it should not go higher than the 14-14.5 volts.
It could be a bad connection, like your stock crappy round glass fuses and holders. You should replace them all. with inline blade type fuses.
Your field coil may have wires with worn spots where they pass through the cases. Same thing on the stator.
The regulator or rectifier may be bad.
Your repair manual has the test procedures for testing these things.
Leo
 
Dare I say the problems are solved!?!?

I think the oil ended up being the main issue, too much oil causing it to bog down at high speeds/uphill. I took her out for a few hours last night with no issues, hit 70 and maintained that speed for quite some time and the bike felt fine. I hooked up a cigarette lighter to the battery and had my phone plugged in the entire time, running high beams, and turn signals, doing anything I could to test the battery and it still ran well.

Garaged it last night but didn't put it on the trickle charger and it started up today after 5-10 tries (it always takes a few to get it going) and I rode again for another few hours with no issues. About 25 miles total since last night.

Shes out back at work right now and I'll be riding her a short distance home tonight (assuming it starts up)

I think it's safe to say I may have my big issues taken care of!
 
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