CB72/77 Gearbox Bearings Clearance ?

Phil-UK · Post by **Phil-UK** » Fri Nov 01, 2013 5:53 am

Hi

Tried using the Message facility to ask a couple of individuals but it doesn't seem to be working so I'll ask via the Forum.

Are the 6305 & 6206 Ball Races in the gearbox meant to be STD or C3 clearance ?
I know they both have snap rings so would be 6305N but the clearance makes a difference to price from a bearing stockist.

I've looked at a collection of old bearings taken from various transmissions and none are marked "C3" but I don't know if clearance is normally marked.

thanks in advance

Phil

G-Man · Post by **G-Man** » Fri Nov 01, 2013 1:27 pm

Phil

I got your message and sent a reply...

G

Tinman · Post by **Tinman** » Fri Nov 01, 2013 8:15 pm

And the answer is?

G-Man · Post by **G-Man** » Sat Nov 02, 2013 3:44 am

Standard or 'normal' clearance is around C2.5 or CN. The tightest clearance is C0 but not usually deployed where heat is involved or where there are interference fits for inner or outer races. C0 would be used where very precise alignment is required.

As the radial clearance increases, so does the axial clearance and the bearing is also able to resist more axial load such as when helical gears are supported.

The difference between 'standard' and C3 is minimal.

G

Tinman · Post by **Tinman** » Sat Nov 02, 2013 6:14 am

Thanks for the explantion G-Man. I figured they'd be a good substitute.

Phil-UK · Post by **Phil-UK** » Sat Nov 02, 2013 6:42 am

Thanks ... STD it will be, certainly cheaper and more available.
The genuine Honda 6305HS is between $11-@%15 over while a 6305NR is about $6 all plus P&P.

Phil

jensey · Post by **jensey** » Sun Nov 03, 2013 3:22 am

Hi,

The lineup of bearing play is a little strange, from tight to loose: C1 C2 C0 C3 C4 C5
C1 is the most tight bearing, C5 has the most play. I use C3 bearings in engines because of the tolerances and the heat / cold cycles in engines. The price difference between C0 and C3 is minimal,

Jensen