Spark plug wire length sensitivity

[CatatonicBug]

I have ready many posts on here over the last year suggesting that if you trim 1/4" of wire off the end, and replace the spark plug caps, it will help with spark issues. However, I was always taught (about cars, mind you) that the length of the spark plug wires is extremely critical to the timing of the spark, since electricity takes time to get down the wire from the coil (via the distributor in a car). I was of the impression that the specific length of each wire was crucial for each different engine, which is why they have different plug wire sets for each make/model of car. Why is it that the wires on an XS can be trimmed without any negative effects?

[Mr.Bill]

I think that with the very small distance from the coil to the plug, really does not matter at all.

All sparkplug sets you see for cars have varying lengths, all depending on location to the coil or distributor.

What it comes down to is cosmetic, not having all the extra wire that is not necessary and possibly damaging if flopping around.

our bikes I would think are the same I would make them as short as possible and not even worry about matching lengths. The xtremely minute time and resistance differance is no biggie.

[hamjam]

electricity ,I will use the speed of something happening at the other end of the wire as in an electron entering the wire pushes out an electron at the other end of the wire, there are other methods depending on your definition of electricity and whether it is ac or dc, (play 'she shook me all night long here)travels at about 186000 miles per second or 982,080,000 feet per second so in a wire 1 foot long and taking 1/4 inch from the end should be a difference of .... you may work this out , but I don't think it is a very big number so I dont think it would have much influence on the spark timing Ford makes ford wires and Chev makes Chev wires so you won't be buying from the competitor ( my opinion )
Jim

[XS1100 Newbie]

It has been my experience for 40 years that it does not make any significant difference. Even in our race car i used to think that the resistance of each wire would make a difference, but that did not prove out. If you think about it, we are using copper wires (most of us). The spark is only detained by resistance, the lower the resistance, the faster the spark will get there. Cut some off the wire, and you reduce the resistance.

[dbeardslee]

I cut all my wires to different lengths without any problems. I get more concerned about a wire shorting out against the motor, so I try to hang them so they don't touch anything on the way to the plugs.

[Silent]

The main reason there's different plug wire sets for different cars is to compensate for the different placement of distributors in different makes of motors. That and to keep the wires away from the exhaust. Other than that it's all aesthetics.