The BSA A7-A10 Forum

Technical (topic titles must be descriptive) => A7 & A10 Engine => Topic started by: GuyboA10 on 01.03. 2008 10:59

Title: dynamo sprocket removal.
Post by: GuyboA10 on 01.03. 2008 10:59
Hey guy's,Re: 53' A10. i am trying to remove the dynamo driving sprocket from the idler pinion spindle which are both still on the inner timing cover. I cant work out how it comes apart, without doing damage. is the sprocket on a thread or does it slide off after taking off the nut and washer? Can anyone help me out ?
cheers Guy.
Title: Re: dynamo sprocket removal.
Post by: bsa-bill on 01.03. 2008 15:18
It's just a good fit on a taper, best to leave the chain on, remove nut and washer and turn engine while at the same time applying (gentle) sideways force to sprocket, ( like a very small pry bar behind sprocket).
You could heat the sprocket prior to this with a heat gun if you have one, it's not usually a great problem to remove.

If you have unlimited funds take the sprocket off the dynamo as well, throw both of them in a bin and buy a toothed belt system.

all the best - Bill 
Title: Re: dynamo sprocket removal.
Post by: a101960 on 01.03. 2008 15:19
The dynamo chain drive sprocket is a taper fit. Once the retaining nut and tab washer have been removed the drive sprocket should be able to be removed by tapping the sprocket with a hammer and a soft drift (copper for example). The dynamo sprocket is small enough to pass through the crankcase opening. I have a belt drive kit fitted to my bike, and the drive is drilled and tapped to permit removal by a puller. As I said though with the original chain set up removal is best achieved with a hammer and a soft drift. It should not prove to be to difficult. I hope it goes well. good luck.
Title: Re: dynamo sprocket removal.
Post by: a10gf on 01.03. 2008 23:15
I remember heating the pinion with a small blowtorch, tapping gently on it all around with a small hammer, all while having it under some pressure using an extractor (that I had to grind down to get the 'claws' behind the sprocket teeth. Suddenly it went "click" and got loose, took some time and patience.
Title: Re: dynamo sprocket removal.
Post by: farmboyuk on 11.03. 2008 11:28
I was just about to ask the same question, since I needed to align the timing marks. The heat gun worked at treat with a couple of taps with a rubber hammer!