1978 Xs650SE Barn Find

I don't want to cheap out, but do not want to pay hundreds of dollars either. Just want something that will keep me dry when riding in the rain.

Anyone have any other suggestions or brands to look at?

Tim
 
I put 50 miles on the bike today. It ran great. I am going to lubricate the throttle and clutch cables and definitely need to re-torque the head as I was getting some more oil seepage once bike was warm.
Just recently after awakening the 79 and doing test rides I too had a head leak seeping. That was was concerning as I want to ride, not tear it down.
A very careful recheck of the head bolts found one to cinch a bit in front.
Now I just warm up the XS with only moderate throttle. Once it is hot, then don't be shy to push it. Run it 50 to 100 miles hot. Shut it off at home and let it completely cool again. Wipe it all clean. Doing this a few cycles of slowly all the way up to temperature and again back to cool. That cooks off any remaining oil from previous and with a little luck, yours may seal up as well.
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:thumbsup:
 
Thanks again for all the input and suggestions on re-torquing the head. Got all bolts torqued to spec. The big ones on the top were a little loose. I started bike and let it warm up and did not see any leaks (previously after 2 minutes of running bike would smoke from the oil seeping).

If weather holds today I am going to ride it into work (30 mile round trip)

My best friend and I have a 150 mile round trip planned for Saturday. Really hope everything comes together!

Tim
 
Well, good for you. Be aware that if you still have the rubber/metal washers on the 4 outside acorn nuts, they will always loosen up and head re-torques will become a part of your regular maintenance routine. Oil flows down those 4 outer studs, that's why they have a rubber sealing washer on them. But rubber isn't hard enough to keep the nuts tight. Many of us swap those 4 washers out for brass or copper ones. These are hard enough to hold the nuts tight but still soft enough to seal the oil in .....

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I've looked close o_O at the original steel/rubber head bolt washers. It is interesting that by design there is a noticeable step (counterbore) on the top. The rubber hugs the threads too.
I've wondered if the design intent was to quiet engine noise?
If they are in good shape, I still use them.
Luckily mine are.
 

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Good afternoon everyone,

I hope everyone had an awesome weekend! Mine was an eventful one to say the least...

Yesterday my buddy and I had a planned 80 mile charity ride, it was approx 150 miles total round trip. The weather was perfect, but unfortunately my bike came home on a trailer. The ride began at his house approx 30 miles from the initial meet up spot. Bike ran amazing with no issues and I thought it was going to be a great day. The bike sat in the sun on blacktop for approx 45 minutes as we awaited other rides to show. Once kick stands were up, about 3 miles in, the bike started to sputter and lost power. After a quick look around I noticed there was no fuel getting to the carbs, it vapor locked. I opened the gas cap and bike started up and seemed to run as normal. I was able to make it to the 1st meeting spot (gas fill-up) 42 miles with zero issues. After fueling up, I went to start the bike and nothing. I was able to kick start the bike and let it run for a little bit thinking the battery was charging. We left for the final meeting spot and after 15 miles the bike was starting to shudder and cut out. I made it another 5 miles before the bike lost power again and it was totally dead.

I got it home and started to diagnosing:

I went and purchased an AGM battery to replace the lead/acid battery and the bike started right up. I grabbed the multi-meter and the bike was not charging again.

Pulled the left side case off and ohm tested the used rotor and it was dead.

I am in the process of talking to Jim regarding a rewound or may go for a PMA set up.

All in all, I made some good memories and met some people who either owned or know someone who owned a XS650.

Tim
 
I am in the process of talking to Jim regarding a rewound or may go for a PMA set up.
Fix what you have. Stock charging system is just fine. Jim's rewound rotor with a solid state regulator will be almost trouble free. You will need to change brushes occasionally.
 
This is why many of us mount a voltmeter on our bikes. It will let you know if charging stops and maybe you can get home before the battery drains and the bike dies, lol .....

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I found a free moment between homeschool and lunch and was able to pull stock charging system off bike and look everything over. The voltage regulator looked alright and connecter was good, wish I could say the same for the rectifier. Below are pictures. It is very corroded. I have not ohm tested anything, but I think the rectifier may play a part in the used rotor dying in 2 weeks. I've also attached a picture of the 2 week old brushes. 1 appears to have worn at a very quick rate.

Tim
 

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I found a free moment between homeschool and lunch and was able to pull stock charging system off bike and look everything over. The voltage regulator looked alright and connecter was good, wish I could say the same for the rectifier. Below are pictures. It is very corroded. I have not ohm tested anything, but I think the rectifier may play a part in the used rotor dying in 2 weeks. I've also attached a picture of the 2 week old brushes. 1 appears to have worn at a very quick rate.

Tim
That stuff should clean up. All that ugly doesn't mean the diodes are bad.
 
Hmmm..mmm
That brush looks broken .spring ?? .the one that wears the most should be the outer one ..
Longer distance traveled
Are you sure the rotor is shorted .. ?? I would measure again on clean surfaces
If problems with the inner brush that may be a reason not charging
Is the rotor on properly and not wobbling or loose ?

Are the tracks on the rotor clean and even ?
The rectifier can be Working as J - Mech says above.

Perhaps enclosed will help
rec1.JPG rec2.JPG
 
Jan- The shorter brush is the inner one - it is hard to tell but the locating cut out for the pin is towards the front of the picture. What would cause the brush to wear so quickly? high voltage?

Everything was cleaned prior to install and the rotor slid onto the crank very easily and looked even when I put everything back together.
 
What would cause the brush to wear so quickly? high voltage?
If the regulator was dumping 12+v into the rotor constantly, it would increase brush wear.... though prolly not as dramatically as that. Did you get those brushes from MikesXS? I've read that those are junk that wear out prematurely, but I've no first hand knowledge of that.
If that rectifier was dropping 1 or more diodes, you'd be losing some of your alternator output back to the battery. The regulator would see that as not enough charging output and run the 12+v to the rotor constantly.... shortening it's life. Everything ties together and a single failure can affect other components.
When I send your rotor back, I'll throw in a modern rectifier in the package. At least we can get that part sorted.
Without me going back through 9 pages, are you running the original regulator?
 
Jim,

I am running the original regulator. When I put the other rotor on I was getting 14.3-14.4 volts when reving the engine, so I thought everything good to go. (boy was I wrong). As my wife says, I should expect to replace things as the bike has 34k miles on it and did sit for 10ish years prior to me finding it in a barn.

Getting a little dishearted, but with help of the forum, I am sure I can get the bike reliable again.

Tim
 
Getting a little dishearted, but with help of the forum, I am sure I can get the bike reliable again.
No worries. With all the help you're gettin' here, we'll get you sorted out eventually. An over 40 barn find can be a little cantankerous. You'll get there.
After you install the rewound rotor and new rectifier, it's best you revisit the regulator. You might find it overcharging.
 
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