Set of 4 pairs of springs for Classic Triumph Twins. We have designed these springs to be suitable for all uses. For a stock engine they are slightly stronger than standard ones and will hold their performance for high mileages without being so strong as to wear out the other valve train components. For high performance use they will take most high lift cams without it being necessary to machine back the cylinder head. They are made from the very best material available and feature a multi-rate to prevent surge.
Norman Hyde valve spring bottom cups are required with these springs..