Hole in Crankcase Cover

[littlebriar]

What is the 1/2" diameter machined hole that is above the kick start shaft that leads into the crankcase? On mine, the hole is about 1/2 to 3/4 in deep. I have attached a picture which shows the one I'm worried about. It looks like it's open to the crankcase. Maybe the casting blew out in the bottom of the hole? I took the cover off to replace the clutch and found some loose metal parts which were all bent up in the bottom of the case. I'm trying to figure out where the parts came from and while looking around I found the hole in question. There's some jagged edges down in the bottom of the hole and I looks like something broke in there. The bike runs fine. I think maybe the last guy to own the bike must have left something in the case when he replaced the clutch.

Any help would be appreciated.

[Bansh-eman]

nothing goes there. it actually gets covered by the gasket when the cover is on. not sure what the intention was of putting it there.

 

take some picts of the metal your talking about.

Edited January 29, 2008 by Bansh-eman

[chevrolet banshee]

What is the 1/2" diameter machined hole that is above the kick start shaft that leads into the crankcase? On mine, the hole is about 1/2 to 3/4 in deep. I have attached a picture which shows the one I'm worried about. It looks like it's open to the crankcase. Maybe the casting blew out in the bottom of the hole? I took the cover off to replace the clutch and found some loose metal parts which were all bent up in the bottom of the case. I'm trying to figure out where the parts came from and while looking around I found the hole in question. There's some jagged edges down in the bottom of the hole and I looks like something broke in there. The bike runs fine. I think maybe the last guy to own the bike must have left something in the case when he replaced the clutch.

Any help would be appreciated.

All i can say is that hole is sopost to be there. now the metal chucks arnt. i don't know why they are there.

 

Chevshee

[littlebriar]

All i can say is that hole is sopost to be there. now the metal chucks arnt. i don't know why they are there.

 

Chevshee

 

 

Thanks for the reply. My hole is completely open at the bottom. I can stick an allen wrench right through to inside the crankcase. Is that normal?

[chevrolet banshee]

Thanks for the reply. My hole is completely open at the bottom. I can stick an allen wrench right through to inside the crankcase. Is that normal?

Ther is a hole in the bottom of your case? Is it like from the outside threw to the trans or something?

[littlebriar]

Ther is a hole in the bottom of your case? Is it like from the outside threw to the trans or something?

No, the hole is shown in the photo on the first post. It's inside the crank cover and leads into the rear of the crankcase. As I look at an exploded view, it looks like the hole does not lead into the crankcase but rather some sort of chamber to the rear of the crankcase. I think I'm OK. I thought maybe the hole had blown through into the crankcase. Of course, if that was the case, I doubt if the thing would run. The engine runs fine so I must be OK. Still can't find out where the mangled metal came from though. I found an exploded view at yamahaoftroy.com and that has helped a lot. Maybe I find find something missing?

[Bansh-eman]

ill say it again, take picts of the metal. if its just shaving its from your clutch

[chevrolet banshee]

No, the hole is shown in the photo on the first post. It's inside the crank cover and leads into the rear of the crankcase. As I look at an exploded view, it looks like the hole does not lead into the crankcase but rather some sort of chamber to the rear of the crankcase. I think I'm OK. I thought maybe the hole had blown through into the crankcase. Of course, if that was the case, I doubt if the thing would run. The engine runs fine so I must be OK. Still can't find out where the mangled metal came from though. I found an exploded view at yamahaoftroy.com and that has helped a lot. Maybe I find find something missing?

Ok sorry, ya that hole go's threw all the way to the other side of the trans. Its normal to have some shavings in your oil. What kinda oil do you run?

 

Chevshee

[littlebriar]

OK, sounds like the hole is not a problem. I couldn't get a close up picture good enough to send. The metal piece is about 1/2" long and appears to have gotten tangled up in the gears. It's mangled pretty bad. Definitely not shavings from clutch wear. I think he must have left a washer behind on the last repair.

Thanks for the help guys. I'm going to give it one last look over and then put it back together.

[BigRed350x]

There's actually a couple holes like that in the banshee case. I know a few of them, and some of the weird mounts (or what appear to be mounts that just weren't machine out) were for the speedo mounting hardware on the RZ streetbikes that these engines were based off of. Some of them are oil relief holes and for lubrication of bearings and bushings... I think that one is for something that was on the RZ engines, but not really sure. Maybe a consideration for future engine modifications yamaha had in mind but never got around to doing??

[RZBansheeMan]

Yeah "BigRed" I think that hole in the pic is for the speedo drive on the RZ, I think it was driven off the clutch gear and runs in above the tranny right under the boss on top of the case where the RZ speedo cable bolts to.

[Lepew]

Is your mangled piece of metal look like part of a snap-ring? Check to make sure the snap-ring for the kickstarter idler gear is still there and the end of the transmission shaft is not chipped off. I have seen banshees loose the snap-ring there and go thru the main gears. Also check the clutch basket nut lock washer. I have also seen the clutch basket nut lock washer break and small chunks of it come thru the clutch.

[FireHead]

There's actually a couple holes like that in the banshee case. I know a few of them, and some of the weird mounts (or what appear to be mounts that just weren't machine out) were for the speedo mounting hardware on the RZ streetbikes that these engines were based off of. Some of them are oil relief holes and for lubrication of bearings and bushings... I think that one is for something that was on the RZ engines, but not really sure. Maybe a consideration for future engine modifications yamaha had in mind but never got around to doing??

Word. :geek:

[Bobman13]

Its For the RZ350 Tach Drive System, It's Cheaper for Yamaha not to change there Mold. Don't worry about it.