Model 50 specifications for 1961

Previously Alan Throssell wrote:

I have found a picture of my bike that was takenaround 1964 you can just make out the seat is "two tone". The only other difference Ican see,is the rear damper cover tops were originally "dove grey".

Regards, Alan

Hi Alan,

Thanks for prompt response, will discuss seat "Options" with Leighton's butlike the "Two-Tone" approach with grey top & black sides. Niceperiod picture of later model 50, especially the 'go-faster' checkered dove grey Girling's. I too have seen matching top spring covers in Dove Grey but as the paint on this is really good, after some TLC at the weekend, will see how she tuns before making any rash decisions!

Fortunately we still have available non-ethanol 98 octane BP âUltimateâ fuel here which I run all my bikes on.

Would you or anyone lese recommend changing the ignition timing from a âstockâ 38? BTDC for this modern fuel?

Thanks again.

Regards Steve

Previously Niall Topping wrote:

Very nice bike, though not as exotic as the ultra-rare BMW R50S behind it.

I find 36 degrees full advance better nowadays to prevent pinking.

Cheers,

Niall

G'day Niall, thanks for the timing tips, that photo was taken at the Bay to Birdwood event several years ago and I have been fortunate to acquire her recently, condition is the same. I am also a member of the local BMW club and there are a few real gems out there but not seen enough road time,. Anyway will post a current photo once the "Refresh" is completed. Hope to have her running tomorrow. One other question regarding air filters. There is some tin-ware in-between the oil tank and battery box with a hole punched in it. Looks suspiciously like this was done for an air cleaner but there is no way this is a straight feed to engage with the carburettor due to the inlet port offset! Current carburettor fitted is a Mk I concentric but may revert to a Monobloc. later A short bell mouth is fitted to the concentric but now very little space before you hit the oil tank. Some sort of filter is desireable, even a SS / brass fine wire mesh filter / bell mouth would stop the rocks but cannot seem to track one down.

Any other ideas out there?

Thanks to all for your kind comments and technical response.

Rgds Steve

Brilliant Neil, will order a filter and check what's inside the fitted carb, as just cleaning out the fuel tank (UGH!) and fitting a new fuel tap / filter.

As she has not run for a while, carb is coming to bits right now, so will check with your details supplied. Got plenty of faster bikes and as I don't need the speeding tickets, looking forward to getting this one going. Someone has already converted her to 12 V but many dodgy connections to re-terminate and double check all is good.

Thanks for your support and look forward to alternative air filter details.

Best regards Steve

Previously neil_wyatt wrote:

Good point Michael, did you ever see the air filter arrangements for the WD 16H for desert use?

I'll say again that I do have a proto type pancake air filter for the model 50 and once found will photograph it but it is basically a slim version of the more common ones.

If it is worth while I may have some made in stainless BUT I have to find it first. Been a while, I know...

Steve, sounds like you are down under: That being the case my advice to you is to use BP Ultimate. It was available when I was in NSW a while back and I believe still E0, so less corrosive elements to worry about in your fuel system. Or solvent to loosen years of grime into your Amal.

Hope to be in NZ early in 2015, I'll be checking on the Ethanol situation there.

Yes Neil you are correct; ex pats living in South Australia and again yes, I only use BP '98 Octane Ultimate' which is, at the moment, E-0. Sorry can't help you with what the score is in Kiwi-land....

Would certainly be interested if you were to make a suitable filter for the model 50. I have a 1940 WD 16 H to rebuild but that's a way off. The Volkes "On Tank Mounted" desert version air filter is a monster!

NowWhile âRefreshingâ this bike also found an additional number on front LHS engine casing.

Numbering is vertical top to bottom, C4825.

Does this mean anything?

It is NOT a casting mark, but stamped with letters and number stamps just like the engine number.

Any ideas?

Thanks for your responses!

Rgds Steve

Previously Niall Topping wrote:

That number C4825 is the Works engine No. and the 'C' denotes Coil ignition, I believe, I have an early 1959 motor with C30, I don't know whether any were built after the move, or if they were, if they had separate engine numbers anymore, the twins didn't.

Thanks Niall, I will order a full factory certificate.

Again thanks to all for your help.

Rgds Steve

Hi Neil, just stripped the 626 for a 'service' and found a much larger main jet, fitted (250). So will purchase a few smaller to 'dial-in' this one correctly. Indeed 210 is correct for a Monobloc / Concentric; needle jet is a 106, slide is a #3. Will check the needle type tonight. Just fitted a new 'stay-up' float kit , filter gaskets etc and Viton needle after removing a lot of crap!

Thanks again for yourassistance..

Rgds Steve

Thanks gentlemen,

I have fitted a 200 main jet and have ordered a couple of others to give some options. Should be running at the weekend and we will see. I have used a Gunsons colour tune for years with success and will check mixturewith that.

Back to the workshop!

Rgds Steve