New XJ750 owner

Too bad the bike isn't new. :lol:

I have been browsing this site for a few days and I think it is a great place for XJ info.

I just picked the xj750 up today and plan on working on it for the next couple of months to bring it back up to a respectable condition.

I dont have any way to post a pic of the bike, but trust me, everything needs a bit of work or replacement; except the frame, engine, drive shaft and wheels.

There seems to be some confusion as to what year it is. Is there an easy way to tell?

Great site!

 

Give us your VIN # and we can tell the year.

 

Great, its:

JYA5G2000CA109xxx

Ill keep the last 3 digits private.

Thanks for any help, I can't wait to return the bike to its former glory.

 

Best I can tell it's a 83 XJ750RK made for the US market.

XJ750RK
5G2-000101
100000
5G2
1981
X


XJ750RK
5G2-150101
200000
5G2
1983
X

Oh, and welcome to the group, send some pics when you can.

 

Ok, now I can post pics. Here are 2 I just took.





Yes, I'm a living room mechanic, who needs a shadetree? :wink:

 

I see a fairly complete bike that just needs some TLC and what better place to do some wrenching than in front of the tv watching your favourite program.

I take it that SWMBO is either very understanding or non existant. :wink:

The big question is, does it run?

 

the latter would be true.

 

Looks like a worthy candidate for salvage. Nothing too extreme. Good catch.

 

Thanks. cost me $300.

Im hoping I wont have to put too much cash in to it.

Currenty Im making a list of what needs to be fixed or replaced as I strip down the bike.

It is going to go slow, because I am noting the order and names of every componet I remove so I can reverse it later during reassembly.

When I come across something I dont know or understand I look it up.

Go figure, thats a habit one gets into after spending 10 yeasr as an Air Force mechanic / technition. :roll:

 

Glad to see those tax dollars weren't wasted. I bought an 86' XT 125 off a Navy Avionics tech who pulled the same thing. He stripped the bike, putting the hardware and parts into individually marked plastic baggies. Man that made reassembly a breeze. Good way to go. Good luck on the beast, I'm certain you'll have a gem on your hands shortly.

 

This is nuts! This bike has WAAAAAY to many wires!

A sensor and indicator for everything. I had to check the make of the bike.... nope it's not a BMW. :lol:

Im half-way tempted to manufacture a custom cannon plug assemply for this beast. Are all Yamaha's this infested with electronics?

 

These early bikes are actually rather simple. Modern bikes have tons of extra sensors and such that make looking at your "mess" enjoyable. I would sit down with the schematic for your make and one by one chase the wires from the device to the plug, mark it and move on to the next. You should have all of them found by the end of two beers. Remember you only have to find one in each connector to get the connector identified.

 

Has anyone just ripped out the computer and wiring harness and all the extra safety circuits, then set up a standard old school electrical system in a XJ series bike?

Is there anything that the computer does that's critical to the operation of the bike and cannot be bypassed or eliminated?

Taking into account the condition of most of the wiring connectors and the fact that the clock box is shot. I can save the rectifier, TCI unit and of course the starting system.

I would put on an after market cable driven speedo and a tach that uses coil ignition timing. Then maybe wire up an oil and fuel meter if it didn't make too much of a mess to do so.

Would revamping the electrical system like this be... sacrilegious or maybe just prudent?

 

It would be more trouble than it is worth. The wirng system is as simple as it gets. If'n I was you, the only conversioin I would consider would be to an earlier 650 that runs just the TDI and regulator such as an H or J model. Not much different than what you already have. The "computer' isn't really a computer on these bikes, just a swich for a little light. Easily by-passed and lived without. I'd offer to fix it for you but I've got two other bikes on the plate and a wife who wants her back porch back.

 

Wow, those exaust pipes were a pain to remove.
Im sure it would have been better to remove the front wheel first.

 

as far as i know the previous owner of my bike took off the nuetral swith, and sidestand switch, i want to bypass the other stuff although i would like to keep my warning light for gas/oil....i can figure out if my brights are on i think :wink: ....but i havent tore into it yet it'll be a month or so before i do...if you figure out any shortcuts lemme know, good luck and nice bike!

P.S. i LOVE to use my bathtub as a parts cleaner, and do short work at the office/home/friends house...my garage has no power so i feel ya bro....i feel ya

 

Once I check out the engine and decide to proceede with reassembly, Ill make up a new schematic.

When I'm satisfied with the electrical design I'll design a new wiring harness.

If it all works as planned, I'll remember to post the diagrams here with a parts lists of anything I add or change, keeping in mind that someone might want to use it.

I still havent been able to pull the engine out of the frame, I have been on anti-alergy pills and they have knocked me out for the last few days. I did try to pull it last night, but I just couldnt pull it over the mounts by myself.

My dad lives in town, I invited him to pop on over Saturday. :wink:

 

Well I decided to give it another try.

My engine is out! Woot!

Though, I think I need a steam cleaner for the spot where it came to rest... my carpet. :x

Oh well!

 

Doh! Congratulations, you have yourself a cool conversation piece in the living room. A little brake cleaner ought to get that out (or Oxyclean). Sorry to hear about your allergies. Mine went ape last week and I'm on shots!!! Claritin is great stuff. I'd get hoppin' on that clean up job, doubtless Mamma isn't pleased.

 

Cool, my dad stopped by and we took the engine to get pressure washed.

It's a lot cleaner, but still dirty. It will do for now.

Next step is to break down the engine.

 

Wow, looks pretty clean to me! Built a '86 XT 125 in my apartment bedroom once back in '89. Had a blast, didn't spill a drop. Of course convention dictated that I put down a sheet of plywood, covered it with plastic sheet, and layered on more cardboard and newspaper. Three days later, wheeled it to the front door and fired that sucker up!

 

This is great! The old owner of this bike said that it wouldnt start anymore so he stopped riding it.

I know why... It would seem a wire pinch clamp worked its way in past the little rubber boot that covers the + post on the starter, effectivly grounding it out.

I took the starter apart anyway, brushes should be good for another 2 years of use. The communtator and windings looked great too.

I tried to break loose the head bolts... they didn't budge, I need to get a big breaker bar.

 

Got my 81 from a fellow who pinched the kill switch wire when he replaced the handle bars. Good on you!

 

Thanks!

 

I have one question after all of those great photos - what kind of bird do you have?

BTW, I just discovered I have a spare speedo/tach set from the '83 Seca parts bike I had. I'm not itching to sell it (I'm a packrat), but if you want to make an offer, PM me.

 

2 albino parakeets. I dont clip thier feathers, so they have reign over my living room.

Thanks for letting me know about the speedo, but there is a big motorcycle salvage yard in town and I'm going to be able to get everything I need from them.

 

I've got a white (but not albino) cockatiel and a sky-blue parakeet, so the play-gym didn't go unnoticed