1978 YAMAHA XS650 SE.

1978 YAMAHA XS650 SE. This 1978 Yamaha XS650 SE is now Tax and MOT Exempt. The XS650 with the 654cc Air cooled parallel twin looks and sounds like an old British bike. Modifications made by Mike include: Pipes and stuff T.C.I ignition XS charge P.M.A ( Permanent magnet Alternator) Chromed engine cases Stainless Steel down pipes Tulip style tail pipes. The YAMAHA XS650 was introduced in October 1969 and produced until 1979. The "Special" cruiser model was introduced in 1978 and produced until 1985. When the Yamaha XS 650 was launched in October 1969 it had one of the most advanced engines in its class of large parallel twin motorcycles. The engine and gearbox are unit construction with the crankcase split horizontally for ease of assembly whereas almost all competitors in its class in 1969, are either unit construction with a vertically split crankcase or pre-unit construction with separate engine and gearbox. The XS650's engine was used in AMA Professional Dirt Track Racing by national champion Kenny Roberts. In 1969 only the Laverda 750S, and the Honda CB350, also launched that year, matched the XS 650's construction and SOHC valve operation. The 1970 model was designated the XS-1. Subsequent Yamaha Xs650 models were XS-1B (1971), XS-2 (1972), then TX650/XS2B (1973), TX650-A (1974), XS650B (1975), XS650C (1976), XS-D (1977), XS-E (1978), XS-F (1979). 1979 was the last year of the so-called "Standards" (an unofficial term commonly used to differentiate it from the "Special". The Special has pullback bars, a teardrop tank, and other differences in appearance). The Es and Fs also came in Special form: XS-SE (S for Special) and XS-SF. From then on they were Specials only to XS-SG, XS-SH, XS-SJ, XS-SK. There was a Special II (Two) model designation in 1978. 1979 (XS-SF-II), 1980 (XS-G), 1981 (XS-H) which were models with fewer chrome parts decals instead of plated plastic on the side covers as well as drum rear brake and wire wheels versus disc rear brake or cast wheels. The Special II was offered until 1985, the last year for the XS 650. The first two model years (XS-1 and XS-1B) were kick start only, with an electric starter added from the 1972 model year on. This had a compression release added to the front left exhaust tappet cover resulting in a square versus triangular cover found on the other exhaust and intake covers. Upon removal of the compression release mechanism in 1974 due to updated starter, the square cover at the left exhaust valve was continued. Standard rear tire is 110/90-18. Special rear tire is 130/90-16. Because the Standard tyre is narrower it will steer a bit more quickly. Because the Special tyre is wider it will tend to be a bit steadier in a straight line. Overall gearing is not changed from the Standard, as the two tires are essentially the same outside diameter. Prior to the XS-B model, the bike had a reputation for speed wobbles but adjustments to the 1975 setup overcame these. 1976 models had the front brake caliper moved to the right fork leg, behind the fork as opposed to in front of the fork. This placed the brake caliper nearer the steering pivot centre-line, requiring slightly less effort to steer. Mid-'77 the front forks had a major redesign: fork tube diameter increased from 34 to 35 mm (1.4 in) and internals were changed (although this also holds true for various years of the same tube size). The entire fork assembly (with triple tree) will swap either way but fork parts are not equivalent. Also the brake caliper changed from a 48 mm (1.9 in) dual piston cast iron design for the 34 mm (1.3 in) fork to a 40 mm (1.6 in) aluminium single piston floating caliper for the 35 mm (1.4 in) forks. The brake caliper mounting lugs on the fork sliders are of different spacing for the 34 mm (1.3 in) and 35 mm (1.4 in) forks so the calipers can't be swapped. The XS 650 was produced until 1985. The last model year was 1983 in the United States, with Canada, Europe and other markets continuing into 1984 and 1985.