1978 XS650 Special Project

Spoke too soon, Had pulled the guide to take the picture (then eat dinner) and did not even notice the plastic was de-laminated and sitting there in the engine at the bottom of the chain before the lower cam chain gear.
I'd say I was darn lucky to do this now

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Working to polish next, but slowing me down getting to that are removing some of these gaskets, They are really stuck on the points/advance covers and sump cover.
Ordered a brass scraper. My gasket remover spray is only good at loosening up residual small thin scraps.
Thx 5Twins, I put Citristrip and some Aircraft Pain remover on the gaskets and overnight its coming off. The Aircraft paint remover seemed to work better.

Is there somewhere I can get a new Points harness? The 2 wires that go from the points up to the coil/condenser joint.If not that can I get the fiberglass insulated wire and the crimp connectors from somewhere? I think I already have bullet crimps in my stash from other bike restoration last year.
so, points harness came in. Thx jpdevol
Gaskets removed later this week.
I aligned cam chain and installed master link. Did not like how the pins peened in so cut it off and installed the spare I purchased and much happer with that.
Put the valve cover back on , since I loosed up the val tappets, I set the clearance for those.
Timing advance parts back in. I'll put points in after engine is put back into the frame.
I also took time to polish up the side covers and tappet covers. Not a mirror finish but a clean look.
Did you pack the grooves full of grease in the outer bushings on both ends of the cam? That's what provides the lube for the advance rod. It lasts a long time but will need to be done again eventually, say in 5 or 6 years .....



The factory recommends a grease with moly in it. I use VW CV joint grease because it has a very high moly content.
There's also an alignment thing going on with the advance rod. There is a locating pin on the points end for the points cam and another on the advance end for the little disc. They must point in the same direction .....

Advance Rod.jpg

Since the holes for the pins go all the way through the advance rod, it's possible to install them pointing opposite or 180° to one another, Doing that will throw the timing off 180°. To aid in proper installation, Yamaha put alignment slash marks on the little disc and the advance backing plate (yellow arrows below). Make sure they point to one another .....

Correct Advance Install.jpg
Thx 5twins. I did not remove the nut on the points cam lobe so I was thinking I did not have to worry about the pins matching on the rod.
I made sure the arrow was on the outside showing rotation.
However, in my photo I took those lines are not on the same side.

I just un do the weights from the disk and rotate to fix it? (well, I have to pull it out anyway to lube the grooves)

I will admit I put the advance rod at the end of the evening sunday and did not open up my service manual to double check what I was doing, just watched the Aussie brat build video which I think he sometimes skips some stuff. so thx for mentioning this!

Yes, your timing would have been 180° off, lol. You'll want to lube up the rest of the advance unit as well. I lightly grease the pivot posts and just brush a light coating of oil on the backing plate. The plate is just raw steel so if any moisture was to get inside the cover, it would rust. Do the springs too. In the future, to keep it lubed, I just dribble a few drops of foaming chain lube on the posts and springs. I do this when it's hot so it penetrates better. You do have e-clips for those pivot posts, right?
came back from an out of town trip last night and took care of this before I forgot.
Grooves were greased and advance rod is back installed.
Edit: forgot to put some oil on the clips/springs. will do that when I get home :)
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Yes, but don't use much, just basically wet it down. In operation, the spinning advance will just fling off any excess lube and just make a mess inside the housing, lol. That's why I like the foaming chain lube. Once it sets, it turns to a gel and sticks and stays in place.
wet it down, got it, thx

I sanded down the tappet covers w/ some dremel wheels I got which are 400 & 600 grit. They worked great to remove the black spots. Followed by 800,1000,1500,2000 grit paper then Mothers to polish. I could stand to clean up the left side cover some more but that's easy to remove and do after the bike is back together. Also removed the chrome chain guard and cleaned up that better than I could if it was still in the bike. While I had the engine out, I cleaned up some more of the connectors in the harness too.

Boys helped me move it into the frame and jockey it into position to put the bottom mounting bolt in.
I still have to prep some things before putting back together like reinforcing the sump filter, cleaning up some of the mounting brackets.
The new sump filters seem to be better than the original ones so has anyone had the new style with the external mesh and internal plate w/ holes fail?
I also need to clean up the junction that connects the cross pipes in the muffler system cause I don't want to be banging that in.
Wondering what I might use to lube that up put together? Aeroshell (high temp anti sieze)?, motor oil? Bearing grease?

Also, the main drive chain guide that mounts on the shift rod below the gear on the back left of the engine, Is there a certain way to adjust it? It can rotate some and I take it put more or less tension/drag on the main chain.

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Yes, I thought that new reinforced filter would be just great, but it's not, lol. At the first oil change, I found it torn out just like the originals do. If you take a close look at one, you'll see they didn't reinforce it at the weakest point, so what good is that? .....


And besides it tearing, one of the magnets fell out, lol. So, not only did I have to patch it, I had to "glue" the magnet back in as well .....

Sump Filters.jpg

But I should add that this all happened before I learned you have to go easy and keep the revs down until the oil heats up and thins out some. Since I learned that, I haven't had many filter tears. I have another new one in my "collection" and so far it's holding up fine.

But, when you patch the rips at that one end on the pointed side, it just shifts the pressure point to somewhere else on that end. Eventually I found one of my patched filters torn on the opposite side from that patched point, I patched that too but now I install a "filter guard" on that whole end of the filter. It's not a 100% oil tight fit but it does cut down a lot on the pressure that end is now subjected to .....


I have several different patterns and each guard is custom made and fit because I discovered the magnet on the back side is located differently from filter to filter .....

I find it easiest to replace the carbs at this stage - tilt the engine forward and slip em in easy.
Thx. I have had no problems slipping them in by just removing the acorn nut for the cam tensioner.

5twins, I was planning to follow your wrapped and bent cover by making it from paper then transferring like you did. I think it would make sense to put some holes in it to allow some oil in and distribute the flow. I would put the holes towards the top knowing it will allow some across the bottom gap as I was not going to JB weld anything
Well, you do want to patch up any tears or holes with JB Weld. If the screen is still there, just ripped, it makes an excellent backer for the JB Weld to adhere to. If the screening is gone, then a sheet metal patch will have to be fabbed up .....




I don't have any pictures of it, but I did put JB Weld all around the edges of the patch once it was installed.