Why would you need to prestress spokes to improve the ride of the cyclist? We just send cyclist out the door with new bikes or new wheels and tell them to come back in 30 days to get them tighten the spokes up again (but in reality we only true the wheels). Is this how your shop operates? If not, you are unusual; if so, you are normal. Do you believe that spokes are made of a magical metal that stretches once and then cures or gets harder and never stretches again? Time to end that myth. Buy Jobsts Brants book The Wheel. Open the book and read it for comprehension. You will find four descriptive drawing that show how the elbow angle will change in the hub flange, how the hub flange will deform to create a better seat for the spoke, how the spoke will have a spring coming out of the hub flange and out of the rim. When they are corrected these four things will make the spoke appear longer and it did not stretch. So sorry there is not a magical metal that stretches once and get harder or an Easter bunny leaving eggs around your yard.Sadly there is not a great process in his book to show you an effective, non destructive, measurable, consistent method to prestress and seat spokes. I will let you know all of the different methods I have learned over the years from professional wheel building companies, professional schools, professional trainers; and one process that was invented by engineers who also invented the wire spoked wheel. The most barbaric methods I learned from my peers. These methods did not damage wooden, steel and plastic rims but not so good for aluminum or carbon fiber /aluminum rims. STANDING ON THE SPOKES! Do not ever do this as a professional! Yes Schwinn taught this method for years in their Schwinn School. I wonder what the difference in loads would be with a 300 pound mechanic and a 100 pound mechanic, with boots versus crocks, bouncing versus standing, damage to the rim on a wooden floor versus concrete, HOW DO YOU MEASURE WHAT YOU DID FOR CONSISTENCY AND HOW IS THE PROCESS NON DESTRUCTIVE?
cyclist who dopes agrees to stick spanner in spokes
There is a School that today still teaches to stick a screw driver or a flat wrench between spokes and twist. The thickness of the screw driver or wrench is undetermined. The spoke tension is unmeasured during the procedure. The round shaft screw driver (used in the manual) damages the spokes. The effectiveness of this procedure is not verifiable and destructive.
WHY is this important to the ride quality of a cyclist? When spokes are not pre-stressed they will become effectively longer and looser as the elbow changes angle and seats into the hub flange. Looser spokes do not transfer acceleration loads, braking loads, or turning loads as effectively as correctly tensioned spokes. Loose spokes also fatigue at a faster rate and break more often than correctly tensioned spokes. A spoke get tightened and loosened 11 times in one rotation of a 700c wheel. 2ff7e9595c
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