Hi, I am in the process of buying a DT175MX 1981. It is claimed to be a stock bike with a 15T front and 49T rear sprocket. However with this setup it only does 50MPH at 7000 RPM (Claimed by dealer). By my reckoning this means it will only do about 57MPH on the redline. The dealer is in the process of fitting a 16T front sprocket as I intend to use it mainly on the road. However surely the top speed stated by yamaha of about 65MPH should be possible with the stock gearing of 15T on the front with out redlining it? I would be grateful for any suggestions or comments on this issue. I nearly said to the dealer are you sure it was in top gear (sixth), but surely he wouldn´t make that mistake?