Bad News

[Nessism]

Keep your head up Dave. Hopefully the damage won't be too bad. There is at least one guy parting a 650 in the For Sale forum, maybe you can pick up a cheap crank from him?

[Dave_17954]

pix

heres some pix of the upper end...these are the good ones. the ugly ones will come when I open the cases lol

[Deivets Cetdar]

WOW! and i am worried about changing my Clutch cable...

You are a pro. I hope you get this fixed. It seems to me that you have tore this engine down within a few mins. "internet time". I am worried bout my clutch cable and am still trying to believe everyone about the "Carb Rebuild" is an easy thing. I didnt even now there were such parts in a bike. Good photos and I hope the best for you. Me I'da sold it but as i said earlier "YOU ARE A PRO!". Good Skills! ( I don't believe in "Good Luck" ).


Man those pictures scare me!

Whew!

Deivets Cetdar

[Dave_17954]

Thanks for the kudos....I sleep with my suzuki service manual under my pillow so I can absorb all the knowledge . I'd guess not being afraid to dive in and getting your hands dirty gives you good feeling of satisfaction when it comes to your bike. I actually felt a little nervous when brian was dialing in my carbs last sat in Indy not that i doubted his ability but that someone else was wrenching on her. I've learned alot from all the guys here in the forums so never be afraid to ask questions and btw they do like pictures lol. I've spent so much time studying this motor its kinda like when your in the service and they blindfold you when you tear down your rifle and put it back together. I actually could have had this thing apart alot sooner but I bought a used minivan that needed brake work done so I'd at least have some wheels in the meantime. Luckily its all metric to so when i get tired of working on one I just turn my stool around and start on the other . I was lucky and never had to clean my carbs (yet) but any of the guys or gals on here would be glad to help just remember pictures man they love pictures.........

[H.M.S.]

In those pics of the first time you rebuilt the engine is that the same #3 con rod that failed this time around? It sounds like you know what your doing so I assume you had ALL of the rods rehoned and the crank polished out after the bearing failed the first time. The heat from a failed bearing will cause the rod to warp out of round and you will get an incorrect reading for your clearances. You said you set them at .07 - .09! I hope you meant .0007 to .0009. And that is a little tight imho. Especially for a high revving engine like that. I would open them up to .0009 to .0012 AFTER you hone the rods and polish or cut the crank again.

[Dave_17954]

when i said .07-.09 thats in mm. according to my notes the #3 shims are set at intake .06mm and exhaust is .08mm. If you convert those to inches they would be intake .0024 and exhaust .0032. Just use the "magic" conversion number that all good machinist learn early on lol (25.4). I used a dial indicater to check my crank and rod cap end and both were well within spec according to factory service manual. the original reason i tore motor down wasnt because the bearings were bad it was because of the tapping noise from the rings running over marks inside the cylinder on #4 and actually although the bearings were worn down the #4 bearing was far worse than #3. There was no lower end noise at all. Numbers 1,2 and 4 are all still tight even tho #4 was the worst off. Will check my torques on those 3 to see where there at when I open it up here very soon.

[Dave_17954]

lower end pictures

Ok I'm posting a link to all the lower end pictures instead of trying to show them all here. Hopefully this will work. First off all the cap nuts were torqued to spec including number 3. looks to be a bearing failure. I'm open for ideas on this one.......By the way the crank looks I'd say its shot along with the #3 rod and bearing or whats left of the bearing. Rest of the motor looks good.

http://s489.photobucket.com/albums/rr252/dave_17531/

[TheCafeKid]

Oil
delivery
Failure

[Dave_17954]

I was wondering about that since them new bearings have no oil holes in them but then again why did none of the others fail? I remember asking the suzki guys about not having that oil hole in the new bearing and they said there was sufficient lube there and wasnt needed anymore and that was where all the older bearings were failing like mine on 3 and 4 because of that hole being there. yet on the crank bearings they actually increased the oiling capacity with the new style bearings.

[reddirtrider]

The oil holes in the rod bearings are to lubricate the pistons. If the new bearings don't have them, they are not correct. Lack of those holes shouldn't cause a rod bearing failure, but would have long term consequences for your pistons.

The oil gets to the rod big ends through the crank. No obstructions in the oil galleries in the crank? Were there oil holes in the crank mains, and were they positioned correctly?

[Dave_17954]

yes.......

[Bribird]

The oil holes in the rod bearings are to lubricate the pistons. If the new bearings don't have them, they are not correct. Lack of those holes shouldn't cause a rod bearing failure, but would have long term consequences for your pistons.

The oil gets to the rod big ends through the crank. No obstructions in the oil galleries in the crank? Were there oil holes in the crank mains, and were they positioned correctly?

Ya the holes used to be for the rod squriter.. Suzuki has dropped that design, and says that "splash oil" is sufficent to lube the cylinder walls and piston pins. I went thru the same deal when I ordered all new bearings for my motor. The design change allowed the oil pressure to not drop at that point, and increased the oil to the crank and rod bearings.

[reddirtrider]

So, since the rods were torqued correctly, miced out and the clearances were in spec, the crank had no obstructions in the oil galleries, and the crank mains were installed with the oil holes lined up with the oil delivery holes in the block, then there's no reason for the bearing failure.

Apparently god doesn't like you. Just kidding, but I don't see any reason for this problem.

One last question, is the oil pump in spec, or did you use a new one?

[TheCafeKid]

Oil porting map is faulty. Its the bane of the PBC motors. If the pressure drops it seems even an instant, or there is enough of a clog somewhere to cause flow problems...boooom... Grenade on wheels... Not to rub salt in the wound, but Ive yet to see a RBC motor have these types of problems on this board...

[reddirtrider]

Oil porting map is faulty. Its the bane of the PBC motors. If the pressure drops it seems even an instant, or there is enough of a clog somewhere to cause flow problems...boooom... Grenade on wheels... Not to rub salt in the wound, but Ive yet to see a RBC motor have these types of problems on this board...

Sure Roller bearins are more reliable, but also more expensive to produce. A vast majority of the internal combustion motors on the planet have plain bearings and survive quite nicely. I wouldn't necessarilly blame this on the type of bearing used.

What baffles me is that it appears to be correctly built and there isn't an identifiable reason for this failure.