The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: A10Boy on 15.09. 2009 19:30

Title: Solid Lead Bronze TS Bush
Post by: A10Boy on 15.09. 2009 19:30

Team
I know we've had a lot of discussions regarding TS Bushes and thought an update might be useful when I saw this on ebay.

http://cgi.ebay.co.uk/B-S-A-C15-B40-crank-bush-SOLID-LEAD-BRONZE-35_W0QQitemZ320414443973QQcmdZViewItemQQptZUK_Motorcycle_Parts?hash=item4a9a3069c5&_trksid=p3286.c0.m14 (http://cgi.ebay.co.uk/B-S-A-C15-B40-crank-bush-SOLID-LEAD-BRONZE-35_W0QQitemZ320414443973QQcmdZViewItemQQptZUK_Motorcycle_Parts?hash=item4a9a3069c5&_trksid=p3286.c0.m14)

I had one made by Mike [no connection] for my A10 during my recent engine rebuild. Its really well made. I had it fitted and line reamed by Derrick at T&L Engineering who also did my crank regrind. Derrick said it pushed into the hot cases just right and fitted really well.

Mike is very helpful and made me one to my requirements it was delivered in just a few days. I would recommend Mike's bushes to anyone who wants a real Lead Bronze Bush instead of one of those pegged steel backed ones.

Title: Re: Solid Lead Bronze TS Bush
Post by: nigeldtr on 15.09. 2009 21:51

Hi,

I have an A10 with a worn TS bearing and was wondering if the bushes have to be reamed for alignment or size or both? Is it not possible to simply drop it into the warm crankcase? Out of interest what sort of clearances are needed?

Thanks

Nigel

Title: Re: Solid Lead Bronze TS Bush
Post by: A10Boy on 15.09. 2009 23:17

As you will see from other threads, after the bush is fitted it has to be reamed for alignment and also to the size of the crank journal. Its best to have the journal re-ground only just sufficient to clean it up.

The clearance crank journal to bush is 0.0015. [or 1 1/2 thou].

The OD of the bush is sized to press nicely into the cases when warmed, if the housing has worn, bushes with larger OD's can be made.

 

Title: Re: Solid Lead Bronze TS Bush
Post by: nigeldtr on 16.09. 2009 05:51

Andy,

Thanks for the info.

Nigel

Title: Re: Solid Lead Bronze TS Bush
Post by: A10Boy on 16.09. 2009 21:30

Nigel

A word of warning although you probably know this. Be careful of running your engine with a worn bush as oil pressure to the big ends will be greatly reduced and can have serious results.  *ex*

Title: Re: Solid Lead Bronze TS Bush
Post by: nigeldtr on 16.09. 2009 21:36

Thanks Andy, I am aware, thats why I have fitted a new SRM pump and oil pressure gauge so that I can keep a close eye on things main will be replaced over the winter when I have some more time.

Nigel