BSA Motorcycles

25 Apr 2015 | Author: | Comments Off on BSA Motorcycles
BSA A 50 Royal Star

BSA Motorcycles

greg.ames at

model identification

BSA A50?

looking to aquire a 1961 BSA. Dont know what model it is. Frame #A508771 Motor #A50.A.792


Sat Feb 08 2014

dbeadsmoore at BSA.

Could anyone help to identify this BSA. Also any ideas if it worth anything as is or to renovate. penrith australia English

richiesta scheda tecnica bsa h 20 del 47

BSA H 20 FURG del 1947

Richiedo se e’ possibile inviarmi scheda tecnica della moto bsa h 20 del 1947.Vi ringrazio in anticipo.


Can you please supply me with your original distributors logos for the mudguards? Just refurbished this motorcycle and after enquiries you were the original distributors for this machine.

bsa 500cc bsaSloper

hello that such I am looking for the manual bsaSloper exploded, and is 500 cc paradsecargar have some file that I have a noce desarmaday completamenete as aj from and thanks go

buenos aires

Mon Oct 07 2013

Lubrication questions

BSA Sloper 500 single

I am trying to resurrect my 1930 BSA sloper 500 single, which I have not ridden in over a decade. When I dragged it out to fire it up again this year, I had some concerns about the oil levels in the engine and the transmission. As a result, I have a number of questions before I start to ride this old bike again.

1) The engine has a dip stick adjacent to the fill spout on the right hand side of the engine. It is a very long stick marked with a 1 and a 2. There is not a clear indication of the full mark, and I am trying to recall whether the 2 means 2 pints low, and the 1 means 1 pint low, or whether 2 is low and 1 is full. Can you please confirm the markings on the dip stick, and where the full mark is?

2) Also, there is a plug with a fibre washer on the left side of the engine casing beneath the crank. I suspected that this is a drain plug for the crankcase, but when I opened it, only a small amount of oil ran out of it, despite the fact that the dip stick is still over the 1 mark, so I now suspect that this drain plug is either clogged (I did fish a wire through there) or that it does not communicate with the reservoir supported by the filler spout and dip stick on the right side of the engine.

So, now I am confused. Exactly what did I drain out of this drain plug, and how and where do I replace this lubricant, and how much do I add (is there a level plug somewhere)?

3) There is a very small tube inlet that angles back towards the rear, on the left side of the engine, high above the crank that appears to have had a metal tab to lock a knurled wheel or knob (although my knob is missing). I suspect that this is a device for oiling the primary chain, but I am not certain what this is for.

4) Could you please provide a complete primer on all lubrication resevoirs and fill, level, and drain plugs and locations of each, for the engine and transmission on a 1930 BSA Sloper 500 single.

5) I would also appreciate a recommendation for all appropriate fluids to use in each location.

6) Finally, there is a dial indicator on a knurled knob on the right side of the engine, close to the dip stick tube. I suspect that this adjusts the amount of oil distributed to the crank bearings, but I would also appreciate a primer on how to set and adjust this meter as well.

7) Do you have any technical manuals, or workshop manuals for this bike that you could share with me, or a source for me to acquire these manuals? I would be happy to reimburse any costs associated with reproducing them if you (or anyone else ) can assist.

I am really excited to ride this old bike, so any and all advice that can be sent promptly is genuinely appreciated.

Thank you so much.


Boston, MA, USA

Here’s a video clip of the bike. Please excuse the gear crunching as I had not yet adjusted the clutch!

1930 BSA Sloper 500 Single – YouTube

Thank you so much for your prompt response, as I am so excited to finally ride this bike.

I will try to take a photo or two to send you when I am next out to my warehouse, but I do not have one yet. I have sent you the maiden voyage video in the meantime!

I have made some progress since I wrote these questions.

Consequently, my inquiry has changed somewhat as well.

I have learned the following since writing my original questions.

1) The dipstick appears to be marked 0, 1 2, so I suspect that this references the number of pints that the crankcase is in need of. Also, I found a full mark on the filler port, which appears to coincide with the 0 mark on the dipstick, so I believe that I have solved that issue.

2) The plug on the left side of the engine case is still confusing me. Apparently there are two plugs with fibre washers beneath the crankshaft level, so I now suspect that the lower one is a drain plug and the upper one is a level plug. However, I am confused as to what is lubricated by these plugs as it seems to be separate from the fill reservoir on the right side of the engine for two reasons. a) The level plug appears to be considerably lower on the case than the fill line and dipstick full level, and b) why would you need a level plug on an engine with a dipstick? In either case, what does this area lubricate, and how do I fill it (through the level plug?)

3) I believe that the tube (which is actually cast into the engine case) and angled back on the left side of the engine is a device to adjust the amount of oil that is distributed to the primary chain case, but I appear to me be missing the adjuster device as there is no knob to turn, just the hole and a spring steel locking tab, which I suspect is intended to rest against the knurled adjuster knob.

4) I would still appreciate a primer on all lubrication cavities, fill, level and drain locations, and recommendations of proper lubricants for each cavity, especially the primary chain, as I suspect that the clutches are supposed to be wet, and I know that non-hypoid is preferred for wet clutches, but I doubt that these were available in 1930. I have been told that a straight non detergent 30 weight is suitable for this area? The primary chain case does not appear to be leakproof, so I am now wondering if it is intended to be dry with only periodic lubrication form the oiler described above, as opposed to being submerged in an oil bath like more modern bikes.

5) I am now reasonably certian that the dial indicator on the right side behind the dipstick, is an oil pump adjuster for lubrication of the main bearings, but once again, I would like to confirm this fact, and how to properly adjust it, so that I do not damage the engine or bearings.

6) There is also a plunger type piston on the right side of the engine which pops out when the engine is running. I suspect that this is an indicator for the rider to confirm that there is adequate oil pressure. Please confirm how this is used and how it is read.

Does the rider reset it during riding, or would low oil pressure allow it to collapse on its own?

7) I would be extremely grateful if you could reproduce and send the manual to me.

8) proper clutch adjustment to avoid gearbox grinding when accessing first or second from neutral.

Thank you so much for your offer to help.

I also sent a separate request this morning with regard to the serial number sequence on a 1921 Monet Goyon Three Wheeled motorcycle. I cannot properly read the first digit, and although thye bike was transferred to me with a 6 as the first digit, it appears to be a g or some other letter or dgit. Do you know what letter or digit these bikes typically had as the first digit on the serial number?

Thank you so much for all of your help and advice. I really appreciate it.

Kind regards,


Matchbox Motors Microcar, Minicar Motorcycle Museum

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