Knock pins R5B

[Greaser Greg]

So I opened this new project motor today and there are no knock pins on the crank bearings. What's up with that? May not be the original motor to the bike? Rd motor?

[Jspooner]

Do you mean the locking or retaining pins in the outer race? Someone probably rebuilt the crank with non OEM  bearings.

[SUPERTUNE]

Are you speaking of the locator pips on the main bearings?
Not needed on RD's crank main bearings.
Yamaha did that as standard for a lot of engines to clock the
outer race for models that have oiling holes on the outer race.
RD's don't need them for location. The oil holes are in between
the lab seal or outer seal and not needed as RD main bearings are a
C3 rated bearing.
So the pip means nothing.
Chuck

[SUPERTUNE]

So yes, like Joe said...was rebuilt before using non oem Yamaha bearings.

[Greaser Greg]

Ok great, thx.
So I'll just fix this, and this!

[Greaser Greg]

Do you mean the locking or retaining pins in the outer race? Someone probably rebuilt the crank with non OEM  bearings.

Yes, silly manual calls them knock pins.
Didn't see any on inner bearings either.

[Greaser Greg]

Are you speaking of the locator pips on the main bearings?
Not needed on RD's crank main bearings.
Yamaha did that as standard for a lot of engines to clock the
outer race for models that have oiling holes on the outer race.
RD's don't need them for location. The oil holes are in between
the lab seal or outer seal and not needed as RD main bearings are a
C3 rated bearing.
So the pip means nothing.
Chuck

Never know what you'll get used sometimes. Do you use non Oem for inner bearings in your crank rebuilds?

[m in sc]

they aren't available any more.  doesnt mean its a bad thing.

I sold a friend a bottom end once, had a bunch of spares and he needed one, and it had flat roller tz bearings on the crank when he opened the cases .

[SUPERTUNE]

You can still buy OEM Yamaha RD main bearings, too pricey, like almost double over the aftermarket high quality "Made in Japan" bearings I use in my rebuilds.
This allows for other upgrades to spend $$ on like using the RM125 rod bearings for the RD cranks.
Chuck 

[rodneya]

they aren't available any more.  doesnt mean its a bad thing.

I sold a friend a bottom end once, had a bunch of spares and he needed one, and it had flat roller tz bearings on the crank when he opened the cases .

You need to run straight cut gears behind the clutch if you want to use TZ bearings or they wont last very long

[m in sc]

oh, they were in there, basket and the primary, i was like 'wtf' . I was shocked when i saw it. was kinda pissed, i sold it cheap too. But, a good friend so was OK. 


i though the oem ones were discontinued. Huh, learned something.