Hi My recently acquired 750SS carbie of 1998 vintage is great in every way except the MPH speedo is reading very high, almost exactly KMH in fact. The odometers are also reading high by the same factor so I was wondering if the bike might have a KMH drive gear on the front wheel? I always thought the drive gear was the same and the speedo differed between MPH and KMH, but it's got MPH marked on the face, so seems to be the right one. Any help most appreciated. Cheers Glen
Glen I think there are some numbers stamped on the plastic housing (they are faint you may need to clean it and get on you hands and knees). I don't know what yours should be but perhaps someone with a speedo that is correct could compare. Cheers Gaz
I may be wrong but I think there's a difference between the speedo drives on the carb and injected models. There's a guy on EBay selling replacement drive gears (which I assume are 3D printed) and he has two listings: Carb is listed as 25 tooth and injected is 27. It seems you could have a compatibility issue, such as a later speedo with the original speedo drive. That's just a hypothetical but it could explain your issue. Beyond that I'd just take everything off and have a look; checking the speedo cable and condition of the drive. If you're feeling brave you could open up the speedo unit but hopefully that won't be necessary.
There are different size speedo drives between carb and injection. I think there's at least 3 different drives
Hi Do you have a link to the eBay listing? I have done a search and come up blank. My error is larger then 27/25 though, more like 27/17! Cheers Glen
Sorry Glen, I'm pretty inept when it comes to phones and the like and I've never been able to figure out how to add links to a post or in other applications. Whats App is easy though. Despite my incompetence, if you search under 'Ducati 750ss speedo drive' his listings reliably come up as 3rd and 4th. The first has a picture of an engineering drawing and the second is a picture of the drive gear itself. The later speedo drive is available to buy new but the earlier carb version has been discontinued. Either search under 'bike parts Ducati' or have a look at Stein Dinse in Germany who are an excellent set up with loads of stock.
Thanks, I have found it listed as 1998. My bike is a 1998, but only because it was left over carbie stock I think. I need to take mine apart and compare to his drawing which is very handy to have. https://www.ebay.co.uk/itm/15420637...%2BEmk%2FCkFAw%3D%3D|ampid:PL_CLK|clp:2047675
I agree. There's only so much you can achieve trawling the internet. Easy enough to take the wheel out and go from there. His drawings are excellent so hopefully they'll prove useful. I noticed on your link that the listing shows postage. I used the EBay app and the listings I found are free post.. Different price as well. They should be £18.
I haven't looked through the whole thread, but mls to kms is 1.609 which is very close to your 27/17 (1.588)...
Hi Yes, £18.00 and I was offered a discount too. However, I messaged the seller telling him my problem and he said I needed the complete assembly, not just the gear so my search continues... Cheers Glen
Just to let you all know that I have overcome my over reading speedo using one of these little Kmh - MPH converter gearboxes. It fits between the drive box on the front wheel and the cable. It took 2 mins to fit and seems to work perfectly. https://www.ebay.co.uk/itm/114431076545
