What did you do to your Yamaha today?

I got my '81 XJ650 Maxim "running" but only on 3 cylinders. Got deep into the electricals after I checked the carbs for the 4th time. Found out that, not my PO, but the PO's PO swapped the resistors in the caps with metal rods, 11k ohm from cap and wire to cap and wire. My PO had put non resistive plugs in.................ooops. Now I know why it can barley idle and was misfiring like mad hahaha. At least finding BPR7ES is much easier than the standard BP7ES.

 

A bunch of time tinkering on the 750 carbs. Found a couple issues. Improvement, but still some hiccups below 2000 rpm. Finished the day putting a new clutch in the same bike and a brief ride in the rain to test it out.

 

Blacked out my bars and installed a new petcock. Still need to hook up the lines and chopa bit off the end of the petcock lever so it wont hit against the bottom of the tank.

And there must have been a defective section on the shrink tubing I used on the bars, as the one small spot on the rh side didnt shrink properly. I'm just gonna tell ppl I just covered up a huge rust bubble on the bars, lol

 

I moved my XJ650 in the garage this weekend in order to make more room for the 1978 XS650 project I just started. There is alot of crud on it that so far I test cleaned and it looks really good underneath (engine panels, chrome etc). custom paint is in good shape too, some scratches but I may end up restoring to its original condition (paint tank, side panels and get a stock seat)
The bike needs nearly the same work I did to the XJ last winter plus some different ones. (hopefully I don't get the speedo scream of death on this one)
I already got carbs rebuilt and started the bike up last friday (not needing carb start).
Unfortunately the Rotor on the alternator was burnt up and battery was not charging.
Moved things around to more room to work around the bike and spread out tools
Already stripped front and rear brake Calipers and Master cylinders.

Bike was acquired on a trade with some gun parts that were collecting dust so it is basically just costing me the parts and time.

Things are going REALLY fast on this one cause of all I learned from the XJ650, extra tools I purchased and all the great Help I got from this forum!!!!

 

I wiped the oil that is slightly leaking from between the bottom fin and my motor onto the stator cover and did some nice Fall riding.

 

Got some new toys to play with...a Gunson Colortune and an actual Yics tool! Still not sure which side of the fence I'm on with the necessity of the Yics, but I suppose since I have one now.... "THOU MUST USETH THE TOOL!!"

The Colortune I've just briefly tried and had difficulty seeing the flame color or change. Probably my eyes. More testing needed...

 

Use it when it's dusk/dark outside, makes it much easier to see.

 

I would still like to find a way to keep the colortune wire from arcing to the deep plug well of an 'X'.

 

Do you use the plastic "periscope" shroud over the plug to shield it? But then again you probably don't have the clearance with the vertical plug orientation versus the angled plugs...

 

Yes, the plastic tube does nothing to prevent sparking, unfortunately.

 

after my gearbox lock-up a month ago, I drained the oil and took off the clutch cover to see if I could see anything horrible, but the clutch drum hides the innards from view, so I am preparing for pulling the motor out. I have seen mention of starter clutch problems - could this lock the engine? Could be stupid question of the week, but as Forrest Gump once said,

 

Made a valve cover gasket for the xj650lj.....

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Good chance the chain guide has broken up , splitting the case will have access to this . Here is what I did get a large wooden palate , put engine on this to keep from marring the engine case. Get several ziplock baggies, a sharpie marker , a large piece of cardboard draw out the shape of the case as you remove each bolt put then through the cardboard to keep each in location . The tools you will need is 10mm and 12mm socket and wrench as well . The clutch basket takes a 30mm socket . Recommend a set of metric allen sockets and a set of torx socket well worth the investment. Blue and red locktight, Yamabond sealant number 4 highly recommended. One caution when you remove the cam tensioner don't rotate engine it can skip time , of course if the chain guide is breaking up this won't matter as cams will need removed . The first engine I did took four days of working on and off , the second engine took two days tear down and reassembled. Take lots of pictures as you go . Cheers

 

Fitting BMW K100 panniers to my XJ.



Just need to cut and paint rail and fit Givi indicators or use the originals.

 

Sandblasted and pressure washed the frame yesterday and got it painted today. Just a rattle can Duplicolor job, but turned out ok. Gloss black with a can of clear coat on top. Tried to blur out the messy shop background on the phone and it made the whole thing look a bit cartoonish.

I considered taking this to a shop for powder coating but figured there was better spots to spend $350 on the bike. But between blast media and spray cans, this isn't exactly free either.

 

Roast, looking good.
I also used colortune but on my XS650 project this weekend. Yes, the spark lighting up masks the flame color but if you look and concentrate on the opposite side of the spark, you can see the flame. I did not even have to move my mixture needle on the XS, it was 3 turns out on both sides even after I adjusted it. 3 turns is where I started. That bike idles awesome.

On the '83 XJ650, I was going to go for a short ride yesterday after work before dark and youth hockey practice. Hit starter the 2nd time and nothing. Wiggle push button, nothing. turn off, on, nothing. Pulled out Volt meter to measure starter coil and no 12V.
went inside cause I knew of the starter thread:
https://www.xjbikes.com/forums/threads/how-to-test-your-starter-circuit.7828/

Being an Electrical Engineer, all I needed was that nice simplified schematic. I could hear the cut off relay click on/off when moving the engine cut off switch. I had 12V (to ground) on the red/white wire of the solenoid coil, shorted the blue/white to gnd and starter turned. OK, so its the push button or wires associated with it.
Pulled the headlight off and shorted the ground to blue/white wire inside the harness plug there and again starter turned. So, My push button likely is dirty. Makes sense. That is what I need to do next, pull that apart and inspect then clean it up. could still be a broken wire in the push button housing but odds are I'd say dirty contacts if not both. While I have the headlight off I think I'll pull some connectors apart and clean as well.

 

I will give it another shot at some point. I suppose it is similar to learning to weld where at first you just see a big ball of light and later learn to look through the light at puddle shape, arc direction, etc. My 750 is actually running much better now. I have vac synched a half dozen times and pulled the carbs as many times (new, flexible airbox boots are worth their weight in gold). Through all that I finally found one slide diaphragm was not seated and also vacuum leaks at the boots into the head. They calmed down considerably after that.

Good job on your troubleshooting. I printed out wiring diagrams and stuck them under the seat with the registration. Between that and a jumper wire, many problems can be limped home, even for us non-EE's!

 

How are you holding them under the seat? I've been thinking about how to store stuff under my seats of my other bikes w/o them getting away or falling off. I have a tool bag and saddle bags on my XJ up front but I wanted to put some papers under the seat of 2 other bikes that either have nothing or I sometimes pull the saddlebags off. Stuff like a copy of my registration and heck, a wire diagram is a great idea.

 

Just a ziploc sandwich bag laying in the airbox/fuse area on the 550 and the 750 has the little "trunk" that is only accessible with the seat pulled. Is the 650 different? I have added a rear bag on the 550 and have another that I need to modify to fit the 750, so those will become storage only because its more of a pain to remove the seat once it has the straps around it. The 550 also has the rear storage compartment accessible from the back, which is kinda nifty.