Forum bmwbike.com

The official pinstripe layout decided by Mr. Huggett with BMW in Münich this
spring is as follows:
Wide line: 5mm
Narrow line: 1,5mm
Distance between the two lines: 4mm

Would this fall on the R51/3 model with raised 2?! inch from the edge of the fender as mine is the later 1952. I will try doing it freehand ( beugler ) and need to order the size.

Secondly....how should the engine finish looks like..definitely not polish i presume but what is the best chemical / manual application to achieve the most suitable dead
metal / shade finish.

Thanks

Jon
Ps. Mark , I have ordered anew...kindly check on this. Sorry for the commercial plug.

Hi Jon

Your observations regarding pinstriping are correct.

Re engine finish, originally, BMW used to shot blast the aluminium castings with stainless steel balls, followed by shot blasting with 1 - 3mm aluminium shot. This brings our the most beautiful dull silver sheen.

Chemical cleaning as never been my favourite as irrespective if the chemicals are acidic or alkaline, it is extremely difficult to neutralise the aluminium. If the aluminium is not neutralised, it can start to discolour and shows signs of efflorescence (leaching out of salts on to the surface). In addition, the chemicals do not remove the deep ingrained dirt very well. If you cannot blast the housing, then only painstaking scrubbing with an abrasive cleaner (my favourite is still the old fashioned VIM for bath tubs) with help.

Best regards,

Mark
Mark Huggett GmbH

I saw an interesting "repair" made to a portion of an engine case that someone had started to polish. First, the polishing looked terrible and of course the person gave up soon after starting. The repair was accomplished with a slightly worn piece of coarse grit sandpaper and a wooden mallet. The restorer simply hit the back of the sand paper with the mallet while moving it over the surface to be "unpolished". the results were not perfect but pretty good (definitely better than the polishing) and very easy to accomplish with almost no special equipment.

When I want to clean the engine case, I use WD-40 and a stiff brush. WD-40 is an excellent solvent and leaves a nice sheen on the case.

Al Olme
Minneapolis, MN

Jon,

Oxidized heads/fins and blocks can easily be cleaned just by using an electric drill with the proper size stiff brass circular brush. Do this operation on dry surface and then apply WD40 with clean rag if necessary to bring it to a "duller" surface look. The brass brush will not scratch the metal surface as some steel ones will.