More Progress

Got the bike ready to strip the wiring harness out of. The headlight bucket and guages are off and when the new ignition gets here tomorrow or the next day I'll be abe to put it right in.

Got an 80 harness on eBay for $35. I did the math and it was cheaper than buying new conectors from the vintage electrical connector site. I figure I should get the thing running first for as little as possible and then start upgrading after that.

Picked up an actual Yamaha Factory Service Manual on eBay that covers these bikes:

XJ650G - 1980
XJ650RJ - 1981
XJ650J - 1981
XJ650LJ - 1982
XJ750J - 1982
XJ750RH - 1981

Ever since I used to build street racers out of 280Z's as a kid I've had an obsession with owning the actual factory manual for anything I'm working on.

Carb rebuild kirs got here today but it will be a while before I use them. My first pass on the carbs will be a rough cleaning and polishing of the slide channels and general un-mucking of the bowls and the rest of the carbs. just to see if I can get it firing. First I have to either grind down some old screwdrivers to fit the screws on the carbs properly or just shell out for a proper set.

I have a few tap and die sets but I see that FJForever selles taps for the various scrws on the carbs and the rest of the bike. Are they odd sizes or will my set do? I assume that data is in the factory service manual but it is coming by media mail and it could be several weeks before I receive it.

So far my only major concern is the intake manifold boots. At least two are cracked. I've read all the info here on the site about repairing them and the numerous fixes sound about like what we used to do back in the day.

My actual concern is in their removal. Only one of the eight securing hex head screws backed out easily. The rest have that feel to them that you start to recognize after snapping your fair share of bolts off in engine blocks. When I apply pressure they don't budge. When I apply a little more I can feel/sense that the head wants to move but it has that kind of resistance that tells you if the bolt does not come loose that you are about to twist the head off of it. Anyone have any tricks? Heating is obviously. I tried the tapping trick but got no love.

Anyone make aluminium replacements? I looked around but it seems there are more chopper parts for the XS bikes than the XJ bikes.

Generally, with a cylinder that was already off the bike, one with hex screws like the Yamaha at least, I'd put it in a vice on the and use the screw heads as a basic guide and drill out the cores of the screws and then peel the remainder out of the threads. Easier than breaking them and then trying to center punch an uneaven surface and line a drill up. With the head on you have a good start and can use it as a guide for size and position. Problem is I am no ready to tear into the engine yet. I wanted to leave that until after I had it running and sussed out the overall condion. No need to rush into a rebuild unless it needs it.

After I determine whether it needs a new ignitor, regulator,etc, I'm positive it will need coils as these are cracked, I'll order all new bearings - front/back wheel, goose neck and probably swing arm as well. Also brake pads front and back and a rebuild for the front brake system and the fuel petcock that I just got off eBay.

I have already lined up some time in my friends paint booth to do the tank, headlight bucket, side panels and perhaps the rims. I just have to get motivated and run then through my blast box to strip off the original pain - what's left anyway.

Other major bits left after all that are new tires, handlebar control pods - ALL my switches are toast, new cables all round and a seat/helmet lock.

Case savers and forward controls are on the 'eventually' wish list.

The cabs are going to take the most time to deal with - assuming of course the engine has good compression all round - I have not done a rack of carbs in probably 15 years other than the side drafts on my MG's (and those are easy). Either way I'm all in now so no turning back

And the hunt for a cheap, running, daily rider while I work on this project continues.

 

Ciberatt sounds like you have all the ducks in a row Im with you on the intake bolts its better to cut the heads off and deal with them than to break them and have to deal with an uneven mess you could always drill a tiny hole on an angle through the head and shoot some penetrating oil in there for a few days have you tried PB blaster or kroil oil before great products kroil is a little harder to find than the PB Blaster but is worth the extra effort check industrial supply houses for Kroil. If your gonna do the carbs you might as well do the shaft seals while you have them off, the manual makes a big deal about busting the rack down but I really dont know why to tell you the truth its not hard to do at all. Good luck to you

 

Yes shaft seals are on my list for the second, final, full rebuild. First I want to get it 'stumbling' and see if there are any rod knocks... With only 10k on it you would think not but then looking at the whack job the PO did on the wiring repairs who knows how hard he road it or if he ever changed the oil...

Drill a hole in the head to shoot in lubricant? Now there is an idea I had not considered... has this worked for you in the past?

I wonder... to avoid the problm in the future maybe drill tiny channels on two sides of each bolt so you could shoot solvent in from the heads...

Speaking of shooting solvent... I read the bits here on the board about using the small wire kit sold by XJForever to clean the tiny passages but was thinking... when doing the Strombergs on my MG's I usually put them in a parts cleaner and use my compressor to blow solvent through the air passages. This has always worked for me on those carbs. I would think it would work on these as well...