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I have a 750 sport as well as my Monster, the sport has 16 inch rims and i have eventually found tires to fit it, they are Avon Azzaros, these are a lot higher profile than the original Michelin's making the outside diameter of the tire the same as the monster, my problem is the speedo drive on the sport has packed up and being meant for the original tire size probably would not be very accurate with the higher profile tires fitted, I cannot get hold of an original one but can get one for a 17 inch wheel, which measuring the monster tires is the same outside diameter as the new tires that are on the sport. to my thinking, I should be able to fit the available speedo drive to the smaller rimmed wheel and get a relatively accurate speed reading , or is there something else that i should be taking into consideration that I've missed - the overall outside diameter on both tires is approximately 23 inches

any thoughts would be welcome
Pete

When I bought my bike, the previous owner installed a later SS front end, complete with the speedometer drive. The speedometer reads 1.3 mph for each mph I travel, which is more due to the difference in gearing between the speedo drive and the speedo. This is likely something you'll have to work through, too.

The speedo drive that came on the Sport is different than what was used on the later Supersports/Monsters (and also different than what was used on my '92 SS). A friend of mine, who parted out an early SS, is mailing me the speedo drive from that bike--if that doesn't solve my issue, I'm going to switch to the black speedometer that I know matches with the later speedo drive.

I'd rather keep the white face, but I don't like overstating my mileage so much and having to constantly "think" about my speed.

Good luck.

Ben

bit of an update -
Dave M had an old one lying around and has kindly sent it to me to see if it is usable, either to repair it or to use as spares. there is a small crack in the casing which i should be able to seal up, araldite is looking favorite as an immediate thought, but perhaps j&b welder may be better,
Will Keep you updated.
Pete.

The early years SS models came with white faces that look exactly like the one on the Sport. Get them for relatively cheap on e-bay.

Cheers,

They're actually identical in size and spec. Only difference is some have a reddish/orange line at 55 mph and others don't. Probably more of a US/British specification than an early/late specification.

As far as my gear issue goes...I got the "new" speedo drive tonight. Had I realized it was in today's mail, I wouldn't have dawdled at work today, and gotten home before 8 pm.

Consequently, I was able to install it. But that took a bit longer than I wanted since I wound up grinding down the spacer so it would fit better. Had to shave about 3mm off. (The one that came with the bike had machine marks, so I have no doubt the previous owner did the same as he was trying to work through this issue.)

Tomorrow (or Saturday) I will take a test ride on the measured mile, and see if this resolves my issue. Fingers crossed.

Ben

Well, after last night's surgery, the Sport now has a speedometer that reads at a 1:1 ratio. (I'm sure it's not perfect, but it's a helluva lot better than the 1.3 indicated miles per 1.0 actual miles I was getting at first.)

Which means, after a little more fiddling/assembly tomorrow, I'll get to use the bike on a real ride. :-) And I get to keep the original, albeit slightly inflated, white speedometer.

Ben

keep us posted on how the 1:1 works out. I tried a 1:1 on my stock sport- and it was way off. recently i have been using a 2:1 - and it is much closer-- but probably about 10% pessimistic.

Oh, sorry, I didn't mean that the ratios were 1:1; I meant that the speedometer is now reading about 1 mile per actual mile traveled.

I don't know the ratio of this speedo drive, but it came off an early 900SS, and worked with a similar white Veglia speedo. Completely different looking than what's on my newer bikes.

I suspect it's the same speedo drive that's on the 851/888 (with the 17" front wheels, of course). If anyone updated to the 17" front end from an SS, look for one of those.

Thanks.

Ben