(NGC) 1980 Yamaha 850 triple help

[BSABEN]

Trying to get a 1980 XS850 up and running. I don't know its history but would guess it sat 10+ years. Cleaned the carbs and replaced all lower jets. Had the bike running enough to go for a 15 mile ride. It quit abruptly at one point but started back up enough to get home. Would no start thereafter. I delved in further and the valve clearances were tight. Re-shimmed so that all clearances are correct (to the loose side of the tolerance). Also went back through the Hitachi carbs. Still will not start. Compression is 135 - 145 and spark seems good (if a tad weak). Since it has electronic ignition i woul assume timing is correct and since it had ran a bit i dont think the timing chain jumped.
Any thoughts?

[Two Checks]

Bet the carbs got some junk in them. You did thoroughly clean the tank, yes?

[oldbike54]

 I would start at the battery , Japanese bikes from that era normally will not run on a weak one , which means it might not be charging properly .

 Also , don't try ordering parts for Hitachi carbs 

 Dusty

[Bulldog9]

Bet the carbs got some junk in them. You did thoroughly clean the tank, yes?

I would check to confirm you have spark, but is likely clogged carbs. These things can be beasts to clean. Best to strip them down, take to a pro to get cleaned (steam/ultra sonic), then re check jets and rebuild again. I rescued a 750 triple a few years ago, took 3 attempts to get clean. ALL kinds of little passageways that get clogged. Have you gone to Mikes XS? They have a decent selection of parts.

May sound dumb, but if you dont want to send out to a pro, buy a couple bottles of pinesol cleaner, strip the carbs down and let them soak for a week, then clean/blow out and rebuild. These are great bikes, and very robust, but the carbs are terrible.

[Rough Edge racing]

 Bike that old with may be the original electronic ignition...could be be issue like you describe,I had two electronic ignition failures and they were as you say, conks out, restarts and conks out for good.....Just because it sparks doesn't mean it's working properly...Of course it might be something else ...

[rtbickel]

Did you check the manual petcock to see if it was in the on or reserve position.? A 77 XS 750 was my first new street bike back in the day and I ran out of gas more than once after I forgot to switch it over.   Also check to see if any of the 3 sets of points have closed up.

[LowRyter]

You might look at the CDI box ($).  My '81 550 Seca would do the same.  The local wrench played around with the charging system (stator IIRC) and it ran well for 15 years.   The last three the problem came back and the trade dealer said they replaced the CDI box (?).

Anyway, I'd guess it's ignition related since it's a common Yamaha issue.

[Two Checks]

1980 model doesn't have points.
I had for a short time the same bike except this was the factory tourer with Vetter designed fairing/bags. It even had am/fm/cb/cassette.
What a gutless wonder. Rode nicely, though.
Didn't have it long enough to work on it.

[Rough Edge racing]

  If you need electronics for an older Japanese bike, very likely from my expereince, this place can be a good deal on some items..They do have stuff for Euro bikes also

       https://www.regulatorrectifier.com/catalog/

[dguzzi]

MikesXS.com  they can help!

[Lee Bruns]

the pick up triggers have a REALLY strange type of wire that goes to them. MIght be a break in the wire, in that last inch or so that wiggles back and forth.

[moto-uno]

  A quick and dirty trick to check for adequate spark is to bend the ground electrode back 'til it's almost straight , and then recheck for consistent spark.
The spark energy requirements are much higher under engine compression than they are lying on the cylinder to test for spark. Hence the electrode bending.
 Peter

[nc43bsa]

I have a factory Yamaha service manual for a 1980 XS850 H/SH.  I do not know why;  I never owned one, nor do I remember ever working on one.

If you need a copy of the wiring diagram, let me know.

[kballowe]

Spray some starting fluid in the intake.  If it kicks, then go back over the fuel supply/carbs