Speedo drive ratio

[Dave L]

I know I asked this question once before but I can't find the answer!What is the speedo gear ratio for my 250 strada worm drive take off?Is it 2:1? I remember Jon saying his used Smiths clocks and they seem to be 2:1.Italian classics seem to have an 83cm cable that joins everything together.Also, I would like to know the same info for the tacho.Thanks,Dave

[Samurai]

I was told by Nigel Lacey that the ratio should be on the base of the Speedo. I can't confirm this as I've not got around to looking.

However, I can tell you that it may take some digging and time to find a correct drive, depending on the ratio you require of course.

I needed a new drive to replace the original Veglia one on my 175TS (Italian version) with 18 inch wheels and searched high and low. Several specialist breakers confirmed they hadn't seen that early version for years.

I finally found a CEV on on eBay in the US but had to swap the worm drive around to get the output cable to turn in the correct direction to drive the Speedo. I'm guessing that this was because it was made for a left-hand side fitment, as the oil nipple ended up being upsidedown too?

I think I might have a link to the drive (15mm axle hole) if it's any help, I'll try and dig it out later. Just be warned that I'm not convinced that it was the correct ratio for my Speedo, as it seems to be consistently 10 mph fast, unless you accelerate very steadily and hold it at a steady speed. Given that I fitted a cycle Speedo whilst I was waiting, plus the fact that the needle always waved a cheery approximation of the speed in any case, I wasn't too bothered in the end.

[Dave L]

Hello Samuri, thanks for the info.I have just had a look at my speedo and there isn't any writing on the bottom,only "walker lic vdo" on the face along with the Ducati logo.I have bought a gps speedo which I'm considering using but I'm not sure of its legality here in Spain.

[Jon Pegler]

Hi Dave
I think the VDO/Walker instruments fitted to the Spanish Stradas and Forzas use a speedo head that works at 1600 revs/mile.(1000 revs/km)
This uses a 2:1 speedo drive gear with an 18 inch wheel.
The Strada with drum front brake will use the same internal gears as the Italian 250/350/450 that has the gears on the hub, behind an external cover plate. Diana, Monza, Mach 1,early widecase etc..
Earlier Spanish models used the separate speedo gearbox. I think Samurai is describing that type of gearbox on an early Italian 175.
The tacho ratio gearbox is also 2:1. This runs from the camshaft, that is running at half engine speed, into a tacho instrument head that runs at 4:1
The speedo and tacho drive cables fitted to an Italian widecase Scrambler, using CEV or Veglia clocks will fit a Strada

Jon

[Dave L]

Thanks,Jon

[Samurai]

Thanks for correcting my misleading answer, I don't have any experience of Mototrans models, as you can no doubt tell

For what it's worth, in case anyone in future refers to this thread looking for info on the earlier bikes with the separate Speedo gearbox, here's the link to the one I purchased https://rover.ebay.com/rover/0/0/0?mpre ... 3599076816

Hope this may help someone in future.

Jas.