As long as the scale is precise it should give you the weight of the bikes
relative to each other.
Accuracy has to do with being close to the truth. Precision has to do with repeatablity.
If you can weigh one bike repeatedly and the scale gives the same reading every time then at least it is precise. It may not be accurate but it will give you the weight of each bike relative to the other bike.
What is he
uncertainty of the scale? How does the dial read? If the scale reads in 5lb increments then the scale is not capable of +/-one half pound - you have too much uncertainty. If on the other hand, it reads down to the ounce then one half pound is well within the scale's uncertainty.
Bottom line - you probably need a better scale.
