First Bike - No Idea What's Going on

Silviculturalist

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I just bought a project 72' xs650 off my brother that he decided he didn't want anymore this is my first bike and while it runs it doesn't do so for very long and i'm looking for some help. I'll try and be as thorough as I can:

  • According to my brother the engine and transmission are solid and were rebuilt by the guy he bought it from.
  • My brother got it running and then promptly let it sit in his garage for two years until I bought it.
  • The main issue currently is that my left cylinder isn't firing, however the bike still starts on one cylinder. It has new plugs, boots, and spark plug wires, so is it safe to assume it's the ignition coil?
  • It's been converted to kick only, this isn't a problem but i'm sure it's important to know
  • There's gas in the oil, my brother claims that's probably just because all it did was sit for a long time. My other friend claims this is because I can only get gas if the petcocks are on reserve. I don't know enough to dispute either.
  • The forks leak and I don't know if it's better to try and rebuild them or just buy new forks?
I really appreciate any help you guys can offer. I'm way out of my depth on a lot of this but I bought this bike intending to learn.
 
Welcome!
First it might be nice if you tell us your level of ability with a wrench so we know how detailed our explanations need to be. Also, give us some good pics of your bike so we can get a good idea of the overall condition. We love pics here. :geek:
 
OK
If this was me I would not run it at all with " Thin Oil " since that can cause damage
Do a quick oil shift and inspect what comes out for metal

The first thing I would do is measure charging voltage across battery .. running
even if it is running on one cylinder only.
Is the battery charged ?

Most likely there is a need for Carburetor service ..
And tank service.
depending on how experienced you are with tools there are different approaches
More info if it is stock and so helps and pictures
 
Fuel in the oil can be caused by a sticking float holding the float valve open, the float level is set to high or there is some dirt on the float valve face. Yes the petcock has to be left on for the fuel to get to the carb. Drain the oil and refill. 20/50 is a best all round and do not use Full synthetic oil as this will make your clutch plates slip.........Do some research on wet clutch motor bike oils.

If your bike is kick only it would pay to check your charging system and let us know what you have. When people convert to kick only they will often put in a PMA system. It is important to confirm this for diagnostics and problems that can arise from PMA's
 
Welcome to the forum from one of the many Wisconsinites, that one guy from Illinois will be along shortly! Be sure to set your forum preferences so you are notified when you get replies to this thread.
When you take your pictures remove the two "round" covers on the LH side of the motor, one is down by the crankshaft, the other is up on the head. We want to see whats inside those covers, and inside the round cover on the RH side of the head too. Don't forget to back up and get pics of the whole bike. Pics will be a BIG help to figgering everything out and getting you on the road reliably.
Yes oil in gas; a left on OR leaking petcock, AND an issue with a carb float valve. Both are very common, um it's rare if one or both DON'T leak on bikes that have sat for a long time. You really need to get a flashlight and check the inside of the gas tank, rust in the tank is VERY common, causes all kinds of carb issues.
Let this thread become a journal of your progress, it will help you know what has and hasn't been done. IF you want an education about EVERY last part of a 1972 XS650 read mailman's thread no finer work exists on the care and feeding of a formerly derelict XS2. It's huge but the first post has an index to take you right to the many parts of working on an XS650. Lots of tech very well explained, with piles of pics (see a theme there?) and entertaining side journeys. He's like having our own private Peter Egan.
 
Welcome to the forum! And congratulations on your new XS2, good luck with your project. Photos man photos! :geek:


He's like having our own private Peter Egan.

Separated at birth? :D
9519A821-8841-4796-93B6-FD4A72F294AE.jpeg 137B6161-0355-41C4-8710-6CCBCD66ACA4.jpeg
 
Alright here's some pictures! Sorry about the quality, it's night here and our garage lights are starting to go. I can take some better ones tommorow or more of whatever somebody may want to look at.

The huge bundle of wires looks a mess because I took all the electrical tape off that was wrapping it up so I could follow some wires better. Worth mentioning that my taillight and turn signals sometimes work(??) But the brake light doesnt come on and the turn signals dont flash. But I figure thats stuff for when I have a bike that moves and wont tear itself apart.

I checked my timing points earlier and they werent corroded and were both set at .014

Also under the seat there is a small 4 cell battery and a rectifier but that was all. I just couldnt take a decent picture of it at the moment

Edit because im remembering things:

I had texted my brother and asked if he had ever checked the float levels, he said he had and they appropriate. I wouldnt know if thats something that will go out of whack from just sitting or not. And I looked in the gas tank and it looks like theres a small amount of surface rust, definetely no chunks or anything flaking off.
 

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Great, what we needed to see!
You checked the points gap so you know some about mechanics.
I'll back up a bit forgive me if I cover things you already have checked or knew.
Three things for a cylinder to run; compression, fuel, spark.
Have you run a compression test on both sides? I do this on every project bike. You should see at least 125, closer to 150 is a strong number but it'll run on anything over 100PSI
Have you checked for spark on that spark plug?
Are you sure it's getting fuel?
If there is ANY doubt about the plugs buy new. That's a bit harder than it used to be the correct plug a BP7ES is not easy to find in the US now. You can find BPR7ES but then you need to find plug caps that are not resister type.
Here's some plug and cap info. https://www.xs650.com/threads/what-have-you-done-to-your-xs-today.32082/page-509#post-702168 if new isn't in the plan heat em up good with a propane torch to clean them.
Then on to the rest of the ignition system; checking, trouble shooting Get a test bulb clipped on the ungrounded side of one pair of points, check for bright light that goes out at the proper time. If the battery set up is not giving you a good 12 volts get a small battery charger hooked to it so you have strong power for the ignition to "get it going". Guess I could write novel here but we are talking about standard old school ignition trouble shooting covered endlessly in many manuals. Um you need to find, download a copy of the factory manual, or much better get a hard copy of it. A Haines or Chilton manual helps with the basics also.
Ignition condensers are a fairly common old part that dies of age. Then the coils plug wires caps can be checked tested. Good grounds through out the wiring harness are often overlooked trouble spots. From the factory the condensers on the top left engine mount have their own ground connection, it should still be in place.
I can see a couple things in your picture that might not indicate the highest quality of engine overhaul work....
xs2.jpg
 
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A bike that looks like yours will almost always have several things that weren't quite right, not discovered or properly fixed, and resulted in the project finally shuffling to the back of the garage. Finding those items through methodical troubleshooting, keeping track of what you have done, and what still needs checking, can often get you back on the road in short order. BUT just hunting for "a problem" can make for a long frustrating slog.
 
As a suggestion, start with ignition... make sure both plugs are firing. Then make sure they're both firing at the correct time. Once you know it's sparking at the right time. Then move on to the fuel system. You need to get access to a compression tester and follow Gary's suggestion somewhere in the mix. Just plan on going through one system at a time. Methodical wins the day.
 
Your tank appears to be a newer Special tank. Can you get us a "look down" shot at the top of it? If it is, it's possible the internal rust may not be all that bad.
 
That's a bit harder than it used to be the correct plug a BP7ES
Yamaha calls for B8ES for XS2s also hard to find. I've been running B8EG in my XS2.
He also may want to check his frame and motor numbers to see if they match. I see the de-compressor has been removed and a newer cover in its place. Someone may not have liked the looks of the de-compressor or the motor may have been changed. Looks like a fun project.
He might want to look through my thread. Frames and cases have been know to crack/break on the XS2. Not as comprehensive as Mailman's but a few problems he didn't have.
http://www.xs650.com/threads/its-past-time-to-start-xs2-resurrection.53396/
 
Your tank appears to be a newer Special tank. Can you get us a "look down" shot at the top of it? If it is, it's possible the internal rust may not be all that bad.

The right side fires just fine. But the left side gets no spark,I swapped the plug, boot, and cable to the right side and then it sparked just fine. I live with two mechanics and they both just told me to replace the ignition coil. I know the wiring is probably a mess on this thing though, there's just so much it feels completely overwhelming
 
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