Thread: km/h speedo for series 2a - part number ?

Originally Posted by JohnboyLandy

Thanks for all the input guys it all makes sense now except for one thing ....

In my suffix G Series 2a 109, the current mph speedo has "1408" written as expected, meaning 1408 turns per mile for 7.50 x 16 size tyres. So presumably the Series 2a km/h speedo (part number 540134) would have a number indicating turns per kilometer, and I calculate that would need to be 1408 x 0.621371 = 875. However, in the listing for 540134 on PA Blanchand's website for this speedo :

Buy Speedo with Trip SN6147-05A Part 540134

I think I can make out the numbers 888. Does that make sense ?

Thanks
John

The speedo in my 2a - out of a S3 109 - has 860. The exact ratio used will depend on possible sets of gears in the odometer drive, and may have changed slightly from time to time. Either 888 or 860 would be probably within tolerance to be equivalent to 875. Or perhaps the number you are trying to read is "860"?

Makes sense, thanks for your insight John. Even at 880, I think it's < 2% error.

Cheers,
John