BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: Greenfield on 08 Jul, 2019, 14:29

Title: B40 speedo drive grease nipple
Post by: Greenfield on 08 Jul, 2019, 14:29
Hi everyone
Does anyone know the size of the grease nipple fitted to the speedo drive of an early B40 (1962/63)? Its about 3/16" across the threads and guessing 30+tpi. Possibly 2BA? Its about the same size as on my A50 but its a coarser thread on that.
Title: Re: B40 speedo drive grease nipple
Post by: TTJOHN on 08 Jul, 2019, 20:56
Not sure but I think it's 3/16" whit, let you know later when I get a chance to have a look at one.
Title: Re: B40 speedo drive grease nipple
Post by: Greenfield on 09 Jul, 2019, 08:06
Its a Smiths 529397. Looking at the parts book the drive is shown as 66-6266 without a grease nipple. To add to this the threaded part is very short, so its difficult to get an accurate thread count. I've a feeling that the A50 might be 3/16" whit.
Title: Re: B40 speedo drive grease nipple
Post by: Greenfield on 11 Jul, 2019, 08:00
Problem solved. It is a 2BA thread on the B40 Smiths speedo drive. Its what they call a short version with only 3 or 4 threads so as not to interfere with the drive mechanism.  :)