Build Log: '81 XS Triple Special.

[Lucky]

I didn't put this in Off Topic, becuse i figure it's a Yamaha, an 81, and another 'odd ball'. Hope you don't mind...

Let me start off by telling you that i had joined the Triple Forum, asked a few questions & got an answer back that 'I should use the search function, because all my questions probably were answered, this wasn't the bike for me (i should buy an XS ready to roll for $1,500) from a person who then tried to tell me  quote: "You CAN'T bend metal with a torch."  The other forum members then backed him up...

I got really pissed, called them names & haven't been back..  was I right or wrong? who cares? I don't...

I love you guys!  :D

So, I've been working on this bike as time allows, probably 10 hours a week..
I spent the first couple of weeks sorting up the wiring. it was hacked up!  i eliminated 6-8 splices/tap & twist togethers. cleaned all the connectors, & retaped the whole loom.

in the process i discovered the 3 causes of the wiring getting FUBAR'ed by the po's.  one was a failed reserve lighting device (switches the headlight to the other filiment if one fails). if the reserve unit fail, the headlights fail completely.  the solution was a simple one wire bypass.  The second cause was a failed lighting relay.  cleaning the contacts took care of that. The third problem was a broken contact board in the left light switch housing for the turn signals.  i fabed up a new contact board.  all the electrics work well now. also made up new battery cables.

interesting to note that on this bike, the lights have their own lighting coil, & the lighting relay is powered directly off one of the (unregulated) wires between the stator & R/R.  the headlight doesn't power up 'till the bike is running at least at idle.  you have to jump the relay to do diagnostics.

the p.o. is color blind, so he didn't even attempt to work on the wiring..

The other thing I have been working on was the carbs.  3 Hitachi sliders. old, abused & sorely needing rejuvination.  they got sonic dipped, new bowl gaskets made, floats adjusted & tuned.  they are a long way from perfect, but they run the bike halfway decent.  Rick G. has offered me a set of Mikunis (much better design) for the cost of shipping, but this bike is strickly low budget for now, so that'll have to wait.

Once i got the carbs worked out & the oil changed, i got the bike to run 'well enough' for now.  Starts & revs up easily. 

Thats when i discovered the next problem: the bike wouldn't shift into second.  Oh Crap!!!

A little secretive lurking on the triple forum & google searches pointed to a broken layshaft bolt in the trans.  (the layshaft holds 2nd & 5th gears) aparently a common problem for these bikes. off came the right engine side cover, drive gear, hivo chain, & the entire clutch assembly.  there was the dasterdly bolt! not broken, but backed completely out and blocking the shift linkage.  the stock bolt is grade 8.8 & aparently a bear to get the stub out when the head shears off, tomorrow it'll get a new grade 12 bolt, lock washer & red locktite.

i have to measure the clutch disks & springs before i reassemble, but either way they are going back in  & will get changed later if needed...

After the right side is back together i have to rejuvinate the aftermarket Jardine exhaust & reinstall that, adjust the timing chain tension (easy to do on this bike)  and probably adjust the valves, although there is a tool for that i'm going to have to either find for free, or more likely, make...

Pics and updates will follow...

--Lucky

[Rikugun]

I think the Tech Talk forum makes sense. Actually, I was hoping to hear some updates on the project.  :)

As far as the Triple Forum goes, sounds like you may have burnt a bridge. You should have expected the search engine comments though. That's typical of any forum newbie experience. Here you are a big fish in a little pond and there you're just another newbie squid. I can see where your nose may have gotten a little out of joint. Depending on how deep your pride resides you may consider eating some crow and return with hat in hand. They could be a great resource. Or maybe just lurk, I dunno....  :D 

It sounds like you've made some significant progress in sorting out various problems. Very interesting about the lighting coil and the reserve lighting device. With certain year Kawasaki's, if the charging system fails the headlight will not come on regardless of the condition of the reserve lighting module and associated wiring. Speaking of the charging system, you didn't mention if it charges? The early 750's had an excitable regulated field and separate rectifier - not so on the 850?

[Lucky]

oh yeah, i burned that bridge, lol.  that's ok.. it was just the assumption that got to me.  i was probably in the wrong, but i care not...

this bike has an integrated R/R like ours, but the coils don't even seem to be coated with epoxy.  they are more like altenator coils. i believe they are a delta design unlike our wye stators with a claw pole construction.  the bike charges well..

i had to laugh where the service manual says thread in the puller bolt in the center of the flywheel & tap with a hammer.  i already had the 3lb sledge out :>

[jasonm.]

Glad to hear the 850 is coming along. Maybe the triple forum guys were a bit too sarcastic...? You cannot bent metal with a torch...but it sure makes it much easier.  You have Hitachis. Maybe find the 750's Mikunis that can be made to work and are easier to service. In fact Mikunis 32 and 34mm(same as Hitachi) are on the XS400, XS360 and many others. SO parts are very common. Is it a Standard or "Special" version? The specials from Yamaha were the 1ts "cruiser Jap bikes. In fact I assembled a few XS850's when I worked at a Yamaha shop.

[Lucky]

It's a Special, aparently a lot more sold so parts are easier to find for them.  it isn't a Midnight Special as I first thought, but i'm fine with that..

I understand that the Mikunis are generaly considered better, but i don't mind the challenge of overenginering.  i had a thing for 350 chevy engines in my youth. give me a Rochester Q-jet over a Holley any day...

Plus the Hitachis are paid for, lol  remember, i said 'low budget' (for now)

[jasonm.]

a guy by me sells a lot of used parts. He probably has 2 or 3 sets of XS750 carbs on the shelf. Not complete...they are likely missing the slides.

[Lucky]

Layshaft bolt backed out.  it was blocking the mechanism & wouldnt shift.
usually the head breaks off.  replaced it with a graded bolt, lockwasher & red locktite..


thje turn signal switch was broken, i made a new contact plate from some thick acrilic sheet.  now if i only had turn signals, lol


another view of the fabed up aircleaner

[fret not]

FOCUS!   ;) :D  Lucky, you are making my eyes strain trying to see what you have there.

[Lucky]

Sorry, that's with my cell camera. i took some pics yesterday with the digital (a bit better). link to the album is at the bottom of this post.  i moved some pics so the links above may no longer work.

Yesterday & rebuilt both petcocks. again, some P.O. hacked them, they were full of grey silicone.  i managed to save the diaphrams, & the rubber bits were actually not bad. I sonic cleaned everything & put them back together. As if one Vision petcock wasn't bad enough.. lol

Also, the rear Valve stem was bent  ??? and wouldn't hold air.  i ended up cutting off the bent part, rethreading the inner stem & inserting a stem valve from a short rubber stem. it'll work for now.  btw, we were talking about it on another post, there is no way a standard rubber stem will fit in these rims. the hole is way too small.

Those are Vision mirrors you see on there as well as the lic plate light.  I've done almost nothing cosmetic, everything needs paint & polish.

The rear brake is completely shot, the pads were run halfway thru the backing plates, & the rotor is trash.  don't know how p.o.'s couldn't know this...  so i have the caliper compressed & i have to remember to stay off the back brake till they are gone thru..

I should be able to take it for a short run around the block today. we'll see what happens, lol

http://s153.photobucket.com/albums/s225/Luckyvision/81%20XS850/