Lucille pulls another one on me....

Yes, this front guide appears to be the 650 motor's "Achilles heel". I think pretty much every long time 650 owner is going to have to deal with it. Hopefully only once though, lol. The originals have lasted all these years (30+) and are just now starting to fail regularly. Hopefully the replacements will do the same. That means most of us won't have to worry about another failure in our lifetimes. The replacement should outlast us, lol.

But, it's not a bad thing having to go into one of these topends. Usually other things need addressing, not to mention just cleaning all the carbon out. Valve guide seals are often all hardened up now, cam chains stretched, valve seats leaking, ring end gaps too big (rings worn) or bores worn. They also benefit from some minor porting (basic clean-up of the "lumps and bumps") and the elephant foot valve adjuster screw mod.
 
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Yes - I agree. In fact, virtually all machinery of any kind has at least one component or system that fails earlier than - or more often than - the others and it appears that, for the XS650, the front guide is it.

I'll keep tabs on mine and will report back any further difficulties.

Pete
 
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Pete's -00 early guide showed up.
Thankyew, thankyew.

Compared to my '71 guide, it has the larger mount base of the '70 guides.
Pete's '70 guide on left, my old '71 guide on right.
XS1B-FrontGuides-01.jpg XS1B-FrontGuides-02.jpg

That means that there were at least 2 variants to the -00 flat guides.

Now, back in post #189, Beags64 reports another early -00 guide.
Condensed pics, original on left, replacement OEM -00 on right.
Beags64-FrontGuide01.jpg Beags64-FrontGuide02.jpg

Beags64's new guide is a mystery. A -00 part number, large/broad mount base, but with a channel shape. What can't be seen is if this new guide is arched, like the -01 guides, or flat/straight like the -00 guides. Beags, help, is it arched?

If it IS arched, expect installation problems with a Type "A" tensioner system.
Ref: http://www.xs650.com/threads/excessive-timing-chain-slack.42215/
 
Some time ago, I ordered o-rings of various durometer hardness, for a different project. Been comparing them against all my front guides, and can take a wild guess at what these guides are.

Here's a durometer chart.
Durometer04.jpg


Using the Shore 'A' scale,
- The MikesXS -01 guides feel about Shore-A 60-70.
- Maxpete's -00 NOS guide feels about Shore-A 80-90.
- My old '71 -00 guide feels at least Shore-A 100, maybe Shore-D 70.

For the sake of interest, here's a chart showing friction vs. hardness, steel dragging over an elastomer.
DurometerFriction.jpg
 
Thanks txxs!

My work life has gone nutty again so I have farmed out the rebuild to an excellent shop in London ON (about 180 km east of us). They should have it done by the end of August in time for me to put some miles on her before the Vintage Yamaha Rally in North Carolina at the end of Sept. I was at the shop the other day and they’d already completed the work on her head - it looked super!

Pete
 
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While reading the many pages of this thread, it just dawned on me. I pulled the bottom plate and side filter on the 2nd oil change. The bottom filter was clean but the side cover filter was dirty. Not grit or sand or metal. I'm used to seeing lead shavings from the old 72 crank, but dirt? My father always told me that cleanliness is next to Godlyness. When I saw the dirty filter, I thought, there is no way I left all that dirt in the cases. (And there is no way.).
Oh, front and back are both from Mike's. The 2nd OC was at about 1300 or 1400 miles. With the Castrol synthetic 10-60 I plan on going the full 2000 before changing again, but now I might lay it over and check the side filter at 1000. If I'm lucky, or should I say we for those of us who went to the soft side, it may be just the initial "wear in" of the rubber to the chain. I am, of course, trying to be optimistic. Oh, and no strange sounds yet.
 
Attention Sportsfans!

As you know, Lakeview and I popped Lucille’s engine into the frame the other day and then my usual nutty life happened for a few days - which totally hijacked my time. I got a few hours in on Thursday and then finally today, I completed the install with engine mounts torqued, exhaust installed, clutch cable connected, carbs and throttle cable hooked up, oil filled, fuel lines primed and.....


After that little test, I finalized the ignition timing (thank goodness for Pamcos and e-advancers), installed the fuel tank and side covers and went for a little ride. There was an odd “sqeaking” sound from the top end - but I put that down to the elephants feet valve adjusters and the new seals and o-rings on the rocker shafts. It was audible, but sounded pretty benign. I had checked the clearance and timing chain - all was well there.

After a few minutes of riding around my neighbourhood, the squeaking sound disappeared entirely and was replaced by.....


Perfection...absolutely wonderful.

I’m so happeeeeeee!!!!

VYR - here we come!!!

MANY thanks to RobinC for helping with the extraction and transport to London and to Lakeview for the transport back to Windsor and insertion back into Lucille’s frame. ..and of course, many thanks to everyone for the kind words of encouragement.

Pete
 

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