I think there is reasonably good evidence a V7 Sport could exceed 120 mph.
First, it is known from a MIRA test, reported in a contemporary magazine article that I have, that the T3 would do about 116. (In fact, I estimated almost exactly the same value from a run I did over a decade ago, though my estimate was based on calibrating my tachometer with milepost markers at lower speeds.)
The V7 Sport, though only a 750, was in a higher state of tune than a T3, with 9.8:1 compression ratio vs. 9.5, and with a 7200 rpm redline, vs 7000. It also had no air filter, of course. [Edit: A V7 Sport is basically a short-stroke T3 (or T), at 82.5x70 bore and stroke, vs. 83x78. It has the same valve sizes (41mm inlet 36 exhaust) and the same carburetors (VHB 30mm) with different size main jets (142 for the V7S and 120 for the T3; the T, without an air filter, also used 142's).]
Using data found in the Chilton Motorcycle Repair Manual of 1976, the top-gear speed at redline for the V7 Sport works out to 126.6, vs. 118.7 for the T3.
Also, data found both in the Chilton manual and in the factory "Work Shop Manual" covering both models shows claims of actual top speeds for the V7 Sport at 130.0 and for the T3 at 121.1, both of those evidently corresponding to engine speeds beyond the redlines.
Whether a stock V7 Sport could really do 130 may seem doubtful, but considering that the stock T3 could really do 116, and noting the ratios between the calculated redline speeds and the claimed top speeds just cited, it seems likely to me that the V7 Sport would do at least 120.
We can convert the known 116 mph top speed of the T3 to a V7 Sport value using the redline ratios: 126.6/118.7 * 116 = 123.7, or using the top speed claims, 130.0/121.1 * 116 = 124.5. So about 124 would be suggested as the actual V7 Sport maximum using either calculation.
I just wish I had one.
Moto
