Author Topic: Still confused about breathing  (Read 2640 times)

Offline BSA_54A10

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Re: Still confused about breathing
« Reply #15 on: 17.12. 2010 12:01 »
Riding BSA's for 40 years leaves one with both thick skin and a reasonable sense of humour so you will have to work really hard to offend me.
The usual support for the long pipe is a couple of P clamps held in place on the end of longer primary case bolts then snugged up with a nut.
And yes it can make a nice sized vent in the cases if the chain grabs it so make sure that it is either firmly secured or you fit a tear away as close to the cases as practicable .
Bike Beesa

Offline Dynamo Regulators Mike

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  • Fareham, UK, 1960 A10
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Re: Still confused about breathing
« Reply #16 on: 17.12. 2010 18:49 »

The oil mist from my breather just seems to end up all over the frame tube just below it. It does seem rather odd that the plunger bikes, where the gearbox sprocket would be closer to the breather, had the pipe whereas it was deleted on the s/a machines.

Hi Ian

Mine was irritatingly messy too. Easy to mistake excess breather oil for a leaky chaincase. The cork seal on the timing side must have no play. I had not realised until this year just how critical this seal is to minimising 'misting' from the breather. I fitted a paper gasket under the cork disk to take up the thou or 2 of slack and the engine became much cleaner.

Sorry if you have attended to this point already. Cannot agree more about the hamfisted corrupting the efforts of the designers.

I wonder if BSA realised after the plunger bikes that the breather in a well sorted engine is unlikely to be a significant souce of oil escape, so saved a few pennies on the tube.

Mike Hutchings
A10, B50, T800; 1,2,3 (& DVR2)
Director, DRL