The bike is at my father's so I'll be able to start working on it and take more picture in the weekend.

This was my first bike ever. I am thinking about buying an other boulevard s40  and use this one for the pieces but I have to admit that now something makes me anxious about buying an other one. This engine usually makes a good run? Should I buy an other model? Looks hard to find a use engine here at a reasonable price.

Don't allow this rare problem sour you on these bikes. We have guys with over 100,000 miles on theirs. Someone already said that if someone over torqued a particular part inside there, it would crack.. Sounds to me like someone was in there and screwed up. Maybe even Heard it crack and decided to sell it.
If you bought it from an individual, I'd consider going to visit,, don't act like it died. Just go talk, ostensibly for more maintenance history, ask about simple things, like sometimes the first start of the day, it needs choked,, once he's comfortable, talk about maybe one day, you might have to go into the engine, ask if he has the shop manual..

Feel for the right time to ask him

Did you kinda want to puke when you heard the sprocket crack?

Or

I heard it takes some real care in some places in there.

I'd probably wanna puke if I heard that sprocket crack..


IDK what you have in it, but if you get lucky, you can get a motor for four hundred bucks.

The ignition changes some years, getting that right is important and some of these guys know and of that by heart.

I'd hate to see you buy a crap motor..

Ya know, if you got another Savage, you could ride, enjoy having a bike and as you learn about these things, keep your eyes open and see about getting a motor and fix your dead one. Then, with two, you could start playing around with one. Most people decide they want to change things a little. Get one like you want it, maybe sell the other?

the beads

Just curious - if you don't mind, what did you pay for the motor?  How many miles are on it?

Your "broken" engine parts are likely to bring you nearly as much as you paid for the engine.  A good low mileage head, camshaft and rockers is worth some money, the cylinder and piston could be in good shape, side cases, clutch, etc.

Here you see the pin installed in the drive gear.  It's a super-tight press fit and shouldn't come out.  Something has to continuously work at it to make the pin come loose.

If the primary drive gear nut is over tightened, the cam drive sprocket can fracture and collapse.  When that happens, there is no longer sufficient pinch to keep the balancer drive gear from moving.  Now the drive pin takes all the load.  The picture of the fractured cam drive sprocket that I previously posted tells the story.

Because the primary drive gear nut is left-hand threads, I suspect it gets overtightened a lot.  Inexperienced mechanics may not recognize that it's a left-hand nut and try to rotate it counter-clockwise to remove it.  It doesn't take much to fracture the cam drive sprocket.  Other wrench turners may know the nut is left-hand, but they use an impact wrench to tighten the nut (probably because they don't have a good way to keep the engine from rotating).  Either scenario can result in a fractured drive sprocket.  If it's only partially fractured and goes unnoticed, it will fail in operation.  Once it fails completely, all the pinch is lost, and the drive pin is now subjected to cyclic stress and inevitable failure.

If anyone doesn't think that these nuts get overtightened on a regular basis, take a look at BlakeEM's nut.  See how the corners of the hex are deformed and folded over in the counter-clockwise direction.

Here you can see what happens to the drive key on the balance shaft.  Oooooo Baby, that hurt so good.  Another Ebay find.