I've started to rebuild my A50 Royal Star. Got the 18" Borrani rim replaced with 19" WM3, powder-coated drum, stainless spokes, new headlamp and associated brackets. I've mounted twin binnacles on the headstock, fitted the original speedo and now want to fit a tachometer next to it. The tacho I got with the bike is too deep to fit in the binnacle so I'm looking for a 'correct' beast.
I've looked at old Smiths references and find RSM3003-06 but this looks too deep. I read also that there is/was a SSM3003 made by Smiths where, I assume, the 'S' means shallow whereas the 'R' means Regular.
Has anyone found/used a shallow tacho, 85mm, 3:1 ratio about 40mm deep below the mounting ring? Or......has anyone fitted a digital equivalent?
The SSM prefix is for speedometers.
RSM prefix for tachometers.
Thanks Julian, simple when you know - I'm happy to learn having not had the occasion to buy/exchange/refurbish tacho/speedo before. SSM = speedometer shallow magnetic! Tachos were almost always called revcounters hence the 'R' I guess.
Regards, Splodger
Update.
I've got hold of a tach RMS3003/14 which is a shallower overall depth so I can now fit it into the binnacle. Shame about the cracked glass but I found a plastics company which will provide an 87mm dia, 2mm thick perspex disc for £1-50 so that's a useful bit of knowledge.
Some advertisers out there offering 'new' tachos which are claimed to be copies of the earlier Smiths models but be aware that they are about 10mm deeper than the originals.
Also, there are some very silly prices for genuine articles but I guess that rarity increases the value!