To Split, or Not To Split (was broken sump bolt)

Yes, #15. Depending on the year of the motor, you should find a copper or rubber/metal damper washer on the plunger .....

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You can easily and safely pull the adjuster screw/spring/plunger assembly out as shown above with no ill effects. No loose parts or anything will fall off inside. Earlier motors used a 2mm thick copper damper washer. Later motors used a 3mm thick rubber/metal washer. If yours is missing, to determine which damper washer is correct for your assembly, measure the length of the adjuster screw. If it is 60mm long, it takes the 2mm thick copper washer. If it is 59mm long, it uses the 3mm thick rubber/metal washer.

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Without checking the serial number, this engine indicates it’s a 1981. The copper washer is in place. Bummer!

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Because a missing damper washer isn't the cause of his engine noise then. But Marty, do a careful cam chain adjustment with the motor running. Tighten the adjuster up until the plunger practically stops moving, then back it out a little to get some in-out motion back. No movement means you're set too tight. It won't hurt anything to crank it in that tight momentarily, just don't leave it set that way. See if making the adjustment as tight as you safely can helps any with the noise. If it's going to help, you'll actually hear the motor get quieter as you tighten the adjuster more.
 
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Throwing this out there. When I set valve clearances, I rotate the engine with the rotor nut feeling and searching for the most clearance and set the gap there. Rotate only in the run direction. (CCW)
That may be bad advice to share. But I do it. Two 79's in a row now have been very quiet after doing this.
 
Because a missing damper washer isn't the cause of his engine noise then. But Marty, do a careful cam chain adjustment with the motor running. Tighten the adjuster up until the plunger practically stops moving, then back it out a little to get some in-out motion back. No movement means you're set too tight. It won't hurt anything to crank it in that tight momentarily, just don't leave it set that way. See if making the adjustment as tight as you safely can helps any with the noise. If it's going to help, you'll actually hear the motor get quieter as you tighten the adjuster more.
Without having these instructions, that is exactly what I did. Once I got it bottomed and not moving, the noise had not changed a bit.

I also ran with one of the valve covers off. There seems to be plenty of oil up there.

So, it was a practice oil change. I’ll focus on putting the original together. Now, where did I put that replacement transmission?

If the Ozark rally happens, I’ll likely be on an XS Eleven.
 
Throwing this out there. When I set valve clearances, I rotate the engine with the rotor nut feeling and searching for the most clearance and set the gap there.
That may be bad advice to share. But I do it. Two 79's in a row now have been very quiet after doing this.

I appreciate that, but I’m sure that’s not it. They went tight after the first run. It pulls hard, so I believe the cam is aligned properly.
 
Yup - it sounds like your front timing chain guide is chowdered Marty.

Sorry if that is the case - I know that you and your crews must be working like mad to keep things moving in the logistic chain.

Pete
 
I'm weighing my options. :shrug:

The engine in my bike is not leaking or smoking. It pulls well in the approximately five miles I operated it. It has noise that is most likely caused by the cam chain tensioner. Otherwise, the history of this 1981 engine is unknown. I am considering removing it and replacing the front shoe on the cam chain and putting the engine directly back in the bike as is. I believe I have the required gaskets.

My original engine is what I ultimately want back in my bike (for whatever convoluted reason). It has over 57,000 miles on it. It is upside down with the bottom cover off. I've been running with a broken transmission for about 15 years. Somewhere in my mess is a replacement. So, I need some seals and I can reassemble and put it back in the bike. It's still going to smoke as it at least needs valve seal replacement. Otherwise it runs good and I know the history from the very beginning. So, it will run.

If I'm going to throw any money and time at an engine, it will be the original one. (There is no logical reason for feeling the way I do.) So, my inclination is to do bare minimum to the spare and run it. Meanwhile, reassemble the cases on the SK engine. Then park it until I have inclination to do a proper overhaul. Or leave it all as is until I do the overhaul. I have an XS1100 that is healthy right now, so I can ride. I also have a long list of priorities like most of you.

In the end, once I'm dead, this bike will end up in the junk heap anyway. No younger person will want it or possess the necessary skills to keep it going.

Thoughts?
 
Yeah - I’d suggest doing the minimum to get the “new” engine running and reliable and then taking your time on Ol’ Smokey. That way, you’ll have a bike to ride while you are repairing the engine - and then you will wind up with a serviceable spare engine that you can either hold onto or sell on the forum to someone else who needs an engine that is known to run.
 
You've now seen first-hand the amount of work required to get into one of these - lots, lol - what with having to remove the engine from the frame and all. When I go into one, I like to do all that needs doing for that reason. On a topend, besides the front cam chain guide, that also includes valve guide seals and a valve job (hand-lapping to re-seal usually), rings if the end gaps are too big (and they usually are), and a new cam chain if the mileage is anywhere near 20K. I also like to install the elephant foot valve adjusting screws (requires some rocker arm grinding) and clean up the ports a bit with a Dremel. This is what I did to mine about a dozen years back and it's given me all these years of good service for just a few hundred dollar cash outlay. It's getting near time to go back in there, mostly because gaskets are failing (still runs fine) but I can't complain. I'm happy with the service it's given me. This time I'll bore it.
 
You've now seen first-hand the amount of work required to get into one of these - lots, lol - what with having to remove the engine from the frame and all. When I go into one, I like to do all that needs doing for that reason. On a topend, besides the front cam chain guide, that also includes valve guide seals and a valve job (hand-lapping to re-seal usually), rings if the end gaps are too big (and they usually are), and a new cam chain if the mileage is anywhere near 20K. I also like to install the elephant foot valve adjusting screws (requires some rocker arm grinding) and clean up the ports a bit with a Dremel. This is what I did to mine about a dozen years back and it's given me all these years of good service for just a few hundred dollar cash outlay. It's getting near time to go back in there, mostly because gaskets are failing (still runs fine) but I can't complain. I'm happy with the service it's given me. This time I'll bore it.
If I read into this, you're saying to do the engine I want to keep. OTOH, once I feel I'm done having a spare, can I get back what what I put in it?

Thanks to those of you who continue to put in your :twocents:
 
I'm pretty sure most of us never get back dollar-wise what we put into these old bikes. I think we get back more in the way of satisfaction and enjoyment from their use. Are you saying you don't plan to keep the spare engine? Seems to me it was pretty handy to have on hand considering your current situation. I have a spare engine as well that I've been meaning to rebuild so I could swap it in while I re-do the original again. I just never got around to it, lol. But now that my original is coming due for refurb again, I'm going to have to get on this, lol. The spare engine came from a $50 parts bike that was pretty beat, so I wouldn't trust just sticking it in there without going through it first.

Let's face it, any hobby is going to cost you some money. As far as motorcycles go though, I feel the 650 can be a very economical choice if you do most of the work yourself. They made near half a million of the things so used spare stuff is still pretty readily available for not too much money. Granted, many of the parts need some TLC and refurbing, but for me that's part of the fun. If I wanted something I could just put gas in and go, I'd buy a new bike. But there really aren't many new bikes that appeal to me, although that new Royal Enfield 650 has attracted me some (I even test drove one).
 
I'll give some thought to the spare engine thing. I have two XS650 projects waiting in the wings, as well as another Eleven Special. No I am not building any old bike to sell. I'm just considering my need or desire for a spare engine and how much to spend on it. I do this because it brings me joy. There's a strong argument for spending my time and money elsewhere. Thanks for the insight.

BTW, I just got off the phone with a friend who just completed his first 1000 miles on the new 650 from Royal Enfield. At the risk of hijacking my own thread, he changed intake, exhaust and ECU. He sounds thrilled with it. Just the same, I may get even more enjoyment out of my old stuff.
 
It is a very nice bike but is much more "refined" feeling than our 650s. I suppose that's to be expected because it's a brand new bike and brand new design, but I have to admit, one of the big things that draws me to our 650 is it's somewhat "rough around the edges" character, lol.
 
It is a very nice bike but is much more "refined" feeling than our 650s. I suppose that's to be expected because it's a brand new bike and brand new design, but I have to admit, one of the big things that draws me to our 650 is it's somewhat "rough around the edges" character, lol.
I prefer the 360 crank to a 270!
 
our 650 is it's somewhat "rough around the edges" character, lol.

HEY - whaddaya mean “rough around the edges???” :boxing::boxing:

The Yamaha XS650 is without a doubt, the finest motorcycle ever built. Why, it came right from the factory fully equipped with:

- an incredibly powerful engine that is as smooth as a baby’s bottom.
...hmmmm, well, ok it’s pretty quick and the vibes aren’t too bad if you put foam Grip Puppies on the grips and you’ve got an @ss that’s tougher than a rhinoceros hide...and, oh yeah, the front timing chain guide hasn’t de-bonded.

- an electric starter that works silently and efficiently every single time.
...OK, the starter often works, most of the time and it sounds good, if you have your ear plugs in...

- an ultra-efficient and reliable AC alternator-based charging system.
..ummmmm, well, the alternator works OK, as long as those fiddly little brushes aren’t too short, the windings haven’t vibrated off the rotor and battery acid hasn’t destroyed the wisely-positioned rectifier...oh yeah, and the spiders haven’t built a nest inside the 1930s-style voltage regulator.

Well, OK, perhaps they are a little rough around the edges, but we’ve got Jim’s rewinds for the rotors and everything else is fixable - and they sure are fun, plus the exhaust note - now THAT is the best!!
 
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If I'm going to throw any money and time at an engine, it will be the original one. (There is no logical reason for feeling the way I do.)

I totally get it. Owning and maintaining these old bikes , there’s nothing logical about doing it. I could’ve had several really nice modern bikes for the amount of money I’ve pumped into these old antiques. It’s purely because we love doing it. You want to keep your original engine because you want to....
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BTW, I just got off the phone with a friend who just completed his first 1000 miles on the new 650 from Royal Enfield. At the risk of hijacking my own thread, he changed intake, exhaust and ECU. He sounds thrilled with it.

Forum member Geedubya in Australia has a new chrome tank RE, and he absolutely loves it! They really are tempting.
 
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