HARLEY 1970/79 Sportster 1971/79 MECHANICAL FULL Advance SPRINGS

These Automatic Advance Unit Parts are the finest available as stock replacement parts. Use them with confidence. Lubricate pivot pins and shaft with high temp antiseize  upon assembly. Designed to outperform and outlast anything out there, this tuneable mechanical advance unit is the finest available. It features a heat treated stainless steel base, pre-lubricated heat treated weights and three sets of color coded springs that allow you to select three different advance curves to meet your engine's requirements. Tuneable Features: BLACK Spring - Allows full advance @ 1400 RPM BLACK  Spring - Allows full advance @ 1400 RPM BLACK Spring - Allows full advance @ 1400 RPM Advantages: Eliminating spark knock and detonation means longer engine life and more low end horsepower and torque. The only mechanical advance unit kit that allows you to adjust your advance curve. A must if you have performance work done. Even minor performance changes can require a different advance curve. in different adds in my e bay store i sell 3 different advance spring buy all three save on shipping. Tuneable Features: Black Spring - Allows full advance @ 1400 RPM (same as OEM) Silver Spring - Allows full advance @ 2000 RPM Gold Spring - Allows full advance @ 2600 RPM The only mechanical advance unit kit that allows you to adjust your advance curve. A must if you have performance work done. Even minor performance changes can require a different advance curve. V-FACTOR in this add you only get 1 set of BLACK springs. BLACK Spring allows full advance @ 1400 RPM Fits Big Twin 1970/1979 & Sportster 1971/1979 Fits Big Twin 1970/1979 & Sportster 1971/1979 Package of 2, (Imported) ONLY IN BLACK sold 2 IN A SET  this add is for 2 BLACK SPRINGS FOR 1400 RPM   only. WANT A SET OF THE DIFFERENT RPMS gold-  2600 rpm or 2000 SILVER  THEY ARE LISTED SEPERATLY IN DIFFERENT ADDS IN MY EBAY STORE. BUY MORE SAVE ON SHIPPING.