xs850 questions (2)

So.. I haven't given up on my xj650. But I bought a bike that's running so I can ride NOW, and I'll get the 650 done aspproject, as I currently still am (painted exhaust pipes last weekend actually).

I've got 2 questions though, since I still don't have manual for this triple yet.

1- which set of wires on this can I test to check alternator? Or better yet, can anyone share just that single page of manual?

2- I've got a spare reg/rec from my 82 xj650. Bought one and didn't end up needing to. Would that work for an 80 xs850, or is there an aftermarket one that would work?

Something is up with electrical system on this relating to alternator or reg/rec. Brand New battery got sucked down in about 10 minutes. There's more plugs on this one than my xj, so I don't know where to jam the probes for my DMM.

Thanks

 

Note - (posting as comment since 'edit' is being weird and a PITA on my phone) It's only got about 7300 miles on it too, so maybe I'm wrong but I tend to think alternator is less likely an issue than the reg/rec. Something is up with charging system tho, that much I know since I just drained a brand new duralast gold AGM in about 10 minutes.

 

Never had an XS850 but when it is running have you tried a multimeter set at 20v across the battery terminals and revved the engine at the same time?

 

Follow the wires from the alternator to the plug that connects to the harness. I think it's the white ones.

 

Something on the bike is creating aHUGE drain on the electrical system

Even if the charging system is completely dead, there's no way a bike would completely drain a brand new battery in 10 minutes

 

Yes, a full battery should allow at least half an hour of riding with no charging taking place.

 

Maybe I'm under estimating my up-time on it. I'm going to start it up and see how long I get riding around here, just for my peace of mind.

I did find that one of the three wires from stator is testing OL. Other two have continuity. Looks like that might be culprit

 

I get MINIMAL voltage increase at 2-3k rpm, even when I rev up into 5k rpm it doesn't break 13v.

The rectifier actually tests okay, I found testing diagram on waybackmachine page for Yamaha triples forum. So it appears I bought another unnecessary reg/rec, when my stator is actually the issue. Blah.

 

Sometimes wires are corroded under the crimp which can cause voltage drop but yours is open circuit. Worth checking anyway before buying any parts.

 

So accurate timing from first start to 'too low to turn over'- 24:23. That includes many restarts from stalling it out. Driving up and down our road (and a neighbors super long paved driveway that told me I could use it to practice too), 10-30mph.

So 10 minutes was a little low of an estimate. The white wire from stator with no continuity has me concerned though, as does the lack of voltage increase @ battery above 13v even at high rpm.

This was supposed to be a ready to ride bike haha. At least this engine works. I'm not opening it up until I get my xj650 running though. I *am* replacing whatever is broken now, and my carb boots bc one is leaking (audibly, and my revs are all over the place at idle). I trust seller that he had the carbs serviced last month, family friend going back years I don't think he'd screw me there. It runs beautiful except this charging system issue. Blah.

Man that was a FUN 24 minutes though. I could just get a backpack full of batteries and have a good little time hahaha

 

I'm going with 'i lost a leg on my stator' as reasoning. Gonna email Len and see if he's got one that'll fit.

 

When it cools off I'll give it a look
Both the bike and the weather. It's 91 out haha. This bike isn't in my garage yet, its parked over at my parents house and the pop up tent garage thing they have is HOT to work in, even worse than the sun. Thanks for the tip. Anything that saves me cracking case open at all is worth looking into

 

Problem identified, conclusively.

I ran the wires down for stator. Where they clear the back of the engine case, they weren't in the holding bracket intended to keep them off the exhaust. Cooked off one of the legs, the one in contact with the pipes.

I also discovered that the connection pipe between both exhaust pipes is missing. It's just entirely gone, pipes open rather than joined to equalize.

I did open the housing and check stator, it's beautiful. Everything in there is pristine. Just that wire got melted a ways down the length.

Needless to say, I ordered new exhaust gaskets so I can drop the pipes (need to remove them to properly run wiring for alternator). Len said they're out of stock for stators, but fyi he said they CAN rewrap them if anyone ever needs that done. I scooped a new one up on eBay that already came though, it's is great condition too. I'll swap that in once I get pipes off since it's got cables in good shape. Then I'll fix the wires in my current one and have it available as a spare. I need to figure out the pipes too.

Debating on spending the $ to have proper pipes welded on, or just using JB weld and DIYing it to hold me over until I can get a 3 to 1 system on it.

 

Decided.

I've got a brand new delkevic 3 to 1 coming. Also bought a lift & rolling seat today since I'm sick of laying on the ground.

Waiting for everything to show up. I'm going to replace stator, install new exhaust gaskets & pipes, do oil change, new air filter, pull and clean carbs & replace boots and intake tubes, and while I've got the tank off I'm going to redo the diaphragm for the petcocks.

No JB weld, I'm going to just do it right and be done. Just waiting on shipping now.

 

Finally got new pipes on. I had to remove the engine guard to do so... So I'm going to have to make sure to not drop her now.

Very glad I did new system instead of JB welding it. Not only was the connection tube between the two sides rusted out and completely gone, but one of the cones was practically falling off because it's so rusty. It was in significantly worse than I'd thought.

If I can ever get this stupid oil filter cover off I'll be able to keep going through my to do list. It was cranked down right by previous owner, and was partially rounded and is rusty. vice grips can't even get a good lock on it. I finally gave up and called it a night.

 

Do you have these or buy them at your local Harbor Freight? Great for removing rounded bolts. Torque your replacement oil filter bolt to spec be easier to remove for later oil changes.

https://www.bes.co.uk/irwin-bolt-gr...bQTyU2xFgosLsvXNJ30behsnLb0En75oaAsonEALw_wcB

 

@Franz nope, I don't own a set. I will tomorrow, hah. Going to go up to harbor freigh and snag a set. I need to get some tools warranty exchanged so it'll be worth the trip.

Since I've gotta wait for new bolt to come anyways, I'm going to just put oil in and some more seafoam and consider this an actual wash for the engine. It was chocolate syrup coming out, so even with what I imagine is a nasty filter, I'll run some clean oil through it for the week and give oil change next week once new bolt shows up and I can get this old one out.

Today I got new exhaust on, carbs cleaned and installed with new boots and airbox joints, new horns wired up. Was a productive day.

Hoping tomorrow to have back up and riding, should be easily done. Then I can get back to work on my xj650. The pipes for that will be done this week and I can get them installed. I've made room in garage to work properly on things (and got a roller seat) so I can get working on making progress on that one again.

 

Does the new exhaust work like my Motad where you don't need to change any carburettor jets?

 

@Franz according to their website... Plug and play, no jetting required.

I'm far from even a competent amateur... But it runs quite smooth compared to the stock pipes. I cleaned carbs but did not jet at all.

 

Then again this is what have now vs what I replaced. Anything would have been an improvement in performance hah. Combine a functional exhaust, cleaned jets, and new non-leaking carb boots & airbox joints, and new oil ... It's hard to know the benefit each individual bit was. Exhaust sounds way better (and is quieter now), engine itself sounds better and runs smoother, idle is stable and doesn't rev to the moon.. it's like a whole new experience on it.

 

I like the exhaust system and the bike. Nice machine. How l wish Yamaha had put a kickstarter on the XJ machines especially with the starter clutch in the crankcases.