New home for an old bike

[hotdog]

Not that it matters much - however, it looks as though it has been attached to a chair at some point in its life. Note the three 3/8" mounting plates on the LHS of the frame.
IMO I'd be stripping it down, the hole in the casing is concerning. It would be a rare occurrence to see a case punctured right behind the frame rail from an external object....
Not what you might want to hear, however, my moneys on either the rod has let go or there has been something caught up in the bottom end that punched the hole in the casing.

 

[59Tebo]

Not what you might want to hear, however, my moneys on either the rod has let go or there has been something caught up in the bottom end that punched the hole in the casing.

I would tend to agree with hotdog. Your picture "zooms" very clearly (without pixilation), and, it looks for all the world, like an internal event, causing a blow-out. A part, or piece of a part seems to have escaped. Yup. Splitting the cases will tell "...the rest of the story."

 

[hotdog]

After having a closer look at a spare set of cases, the hole is directly outboard of #4 crankwheel.
Possibly a broken clutch spring or loose clutch ball has been picked up and wedged between the case and crankwheel..?

Either way I'm curious to see what has happened there.

 

[TwoManyXS1Bs]

Agree with hotdog and 59Tebo, that case needs to be opened up. Not a critical structural area, but crankcase venting pressures will have oil blowing outta that hole.

It's in the upper case half, about an inch above the case parting line.


The red arrow in these cutaway pics shows the approximate location, about an inch above the case split surface.


Having the hole welded closed shouldn't be a problem, since that's not a structural area, and the right #4 flywheel has some clearance in there...

 

[geedubya]

Hey guys today I purchased what appears to be a XS-1B. It’s pretty rough and has had some questionable modifications to it. She does run but I haven’t ridden it yet and I don’t imagine I will for some time.
The problems so far are the electrics, the head light and front indicators don’t work and the seller also said that voltage regulator is also dead. There are a few extra tabs welded onto the frame to support a side cart too that will have to go.
The rear shocks have been moved from their original location but can be moved back to stock and the chain guard has been modified to accommodate their new position.
I’m not sure if the swing arm is original either? Some guidance on that would be great. The speedo has given up on life and the tank and side covers are finished off with a interesting choice of a rattle can blue.
The head is cracked where a larger gauge bolt has been used to marry the exhaust flange to the head. Any point trying to save it or should I look for a replacement? And will a head from any year fit or will have to be for an XS-1B?
I have owned a CD 650 before but that was a SH and was in better condition.
All and any help would be much appreciated

G'day Mate,

For $150 South Pacific Pesos I would buy it if you cannot get it as a runner you can always sell the parts.

IMHO stay with it, price is right and it looks mostly there.

Depends what you want to do, chop-it, cafe, restore, up to you.

GeeDub

Townsville

 

[Ozplumb]

Hot dog you were correct about the side cart. The guy I bought the bike off also had that sitting in his shed. It was rougher than the bike if that’s possible.
Twomany thanks for the detailed pics. On closure inspection it looks like you guys are right. On the right hand side of the hole there a pushed out section,(which may confirm the internal damage theory) that has a slight bur on it. I got about 5-10mm of penetration with a wooden skewer in the hope it was more superficial.
Geedub- you might be right. I should just grab it. As long as the hugs and kisses doesn’t see it arrive then I never spent the money.
And Skull I went down to the cop shop after work today and the very helpful police officer checked the engine number, frame and rego plate. She couldn’t find the number plate or frame number on her computer but she did confirm that engine wasn’t stolen

 

[TwoManyXS1Bs]

I suppose you could clean that hole area, and patch over with jb-weld and wire/screen cloth.

Otherwise, would need to do a complete teardown for welding.
Professional tig, or could try muggyweld.

https://www.muggyweld.com

 

[650Skull]

Good news on the motor info.......Bit of a question as to why the frame couldn't be found.........at least it isn't on the stolen list.........Did the check also include rebuild -able write off's??

I concur about the hole in the cases..........looks to have come from the inside............i would be doing a tear down for sure.

There was some differences around the tunnel area between the early XS1/1B and later heads and i think the dowls???...........XS1/1B expert 2M may pipe up.......

 

[TwoManyXS1Bs]

...There was some differences around the tunnel area between the early XS1/1B and later heads and i think the dowls???...........XS1/1B expert 2M may pipe up.......

Hey, Skull. Yeah, the big thing is the bridge in the 70-71 cylinder's camchain tunnel.

And, the camchain tensioner systems.
The only tensioner that'll work on these early cylinders is the sprocketed type "A" or "B".

Starting with the '72 XS2, the bridge was removed, and the tunnel widened.

This open tunnel allows the use of the later camchain tensioner systems, with the wider rear slipper.

Another detail is the enlarged head gasket surface, with grooved periphery, on the 72-on heads and cylinders.

A complete '72-on head and cylinder group can be fitted onto the 70-71 lower, but not the other way around, unless the camchain, sprockets, and tensioners are addressed...

 

[59Tebo]

2M, were there any advantages to the sprocket-type tensioner? Did they switch to the problematic plastic tensioner just to save money? Which (if either) would you consider to be more effective (better?)? Could a later motor be modified to accept the sprocket-type tensioner? Is this too many questions? With the motor for "The Basketcase" ('75) in pieces for a top-end refresh, I want to reassemble it using the best stuff available.

 

[TwoManyXS1Bs]

... Is this too many questions?

Hey, Tebo. Naw.
I'll see your "too many questions", and raise with "answer overload".

Let's start with Inxs's tensioner thread.

http://www.xs650.com/threads/cam-chain-tensioners.1056/

The "256" sprocketed tensioner applies a "point" load in the camchain path, which I feel is inferior to the later, gentler, curved rear slipper. Honda's tensioner evolution also went from sprocket to curved slipper. Curved slippers are a de-facto standard nowadays.

And, that sprocket has the 8mm "256" pitch. Not really suitable on a different pitched "447" camchain.

Do a forum search on "tensioner", posted by "Twomanyxs1bs".

You'll want to ensure that you have the tensioner with the lock nut.
Do a forum search on "tensioner nut", posted by "5twins".

The front slipper is the problematic one.
Have a look at JimD54's front guide mod.

http://www.xs650.com/threads/cam-chain-guide-mod.51730/

 

[59Tebo]

Thanks, 2M! Sometimes the only thing more expensive than a question, is the answer... Yes, I should've remembered reading those before.

 

[Ozplumb]

Skull the check didn’t include if it had been written off. I’ll pay for one online and see what comes up.
So I’ve got an update on the engine and that mysterious hole in the lower casing. I pulled the engine the other day and took off the top end. The amount of sealant and mismatched bolts were crazy.
So the good news, it seems the hole in the casing wasn’t from any internal event and more so some excessive screwing. I’ll add some photos where you can see daylight through the hole. Hopefully it’s just a weld job and that’s that.
The bad news is the wear on the cam chain tunnel. It looks like the cam chain has been running wild and free for a quite some time causing a fair bit of damage in the process. My question is will this damage cause problems after the rebuild? I understand that there isn’t any repair for damage like this. Even the cam guide bracket has copped a fair bit of damage too. Also the top ring on one of the pistons fell off in 3 pieces after I removed the cylinders. Might explain some of the compression issues. Thanks for your input guys

 

[Ozplumb]

Another photo off the hole in the casing

 

[5twins]

I think what may have happened is someone attempted to do a Heli-Coil repair on the case screw hole and drilled too deeply, right out the back side of the case, lol.

 

[gggGary]

Doesn't look like it's structural, or into an oil passage, JB weld and paint?

 

[TwoManyXS1Bs]

I see that the plastic is completely missing from your bottom slipper. The bottom slipper blocks can still be found on eBay. Recently discovered that there's 2 versions of the early type "A" slipper block, different clearance notches to clear the bottom of the cylinder's tunnel bridge. More info in here:

http://www.xs650.com/threads/excessive-timing-chain-slack.42215/

 

[Ozplumb]

Yeah all the plastic strips were either falling apart or were coming away. Twomany I had a look around but couldn’t find anything to replace the bottom slipper block. Could you give me a nudge in the right direction?
Thanks mate

 

[TwoManyXS1Bs]

On eBay, search "yamaha 256-12241-00".
I see 4 available. But that's in the USA...

 

[Ozplumb]

Thanks for that and thanks for the link. After reading I fear I might have the same problem if I get one of the slipper blocks off eBay. I too have the early design with the extra lip on top.