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Motorcycle Discussions => British Bikes => Topic started by: Sidecarcrosser on October 16, 2011, 02:27:40 PM

Title: T140E Timing Side bearings.
Post by: Sidecarcrosser on October 16, 2011, 02:27:40 PM

Hi All,

Could anyone help again please? I need to change the main bearing on the timing side as the crank I have just got has a smaller 1 1/8 bearing. The old one is a 6306 bearing but the internal diameter is now too big at 30mm. Does anyone know the part number please or can explain why this is different.

Grateful for any help

Thanks

Title: Re: T140E Timing Side bearings.
Post by: L.A.B. on October 16, 2011, 04:02:58 PM

Quote from: Sidecarcrosser on October 16, 2011, 02:27:40 PM

I need to change the main bearing on the timing side as the crank I have just got has a smaller 1 1/8 bearing. The old one is a 6306 bearing but the internal diameter is now too big at 30mm. Does anyone know the part number please or can explain why this is different.

Unfortunately, what you appear to have got is a pre-72 650 crankshaft which takes the 2-13/16 x 1-1/8 x 13/16 Imperial timing side bearing which broadly converts to 71.5 x 28.6 x 20.6mm.

The 72-on metric T/S bearing is 72 x 30 x 19mm (6306), therefore the Imperial bearing doesn't fit the 72-on T/S case and the metric bearing doesn't fit the pre-72 crankshaft.

Title: Re: T140E Timing Side bearings.
Post by: Sidecarcrosser on October 16, 2011, 04:34:56 PM

L.A.B,

Many thanks for your help - i was assured it was the crank for my bike so I guess I will ask them to swap it over. It's a shame i have just renewed the sludge trap which wasn't easy - had to machine the plug out. So lets see what happens next.

thanks again