For good sound quality on sport and unfaired motorcycles, earplug speakers beat helmet speakers. If Koss earplug speakers (#3081 $17.00) do not fit snugly enough, an improved version can be made by combining a pair of Etymotic earplugs (#1030 $15.00) with the Koss speakers*. The Etymotic earplug's silicone ear pieces remove with just a bit of force and no damage. Shorten the Koss plastic sound tubes to half the original length and insert them into the Etymotic's silicone ear pieces. The fit is perfect, they stay in ears better, and the sound is unaffected. The modified earspeaker is sensitive to proper insertion, so care is needed to get them in right. A bit of saliva on the mushroom pieces can help. Putting them in too far may close the passage through the Etymotics and kill the sound, but when inserted correctly they provide a significant noise reduction and excellent sound. Donning a helmet usually does not affect placement but it can. Many other types of ear plugs may be combined with Koss earplug speakers, so experimenting can produce a personalized setup.

Jabra ear Gels (#3078 $9.00) work well with most 'ear bud' type speakers. They can also be modified for improved fit and function. Use a moto tool or a sharp knife blade and sandpaper to remove any pressure points that are causing discomfort.

Audio cords are not difficult to modify. Longer cords can sometimes unexpectedly catch on tank bags or riding clothing and be distracting. The ideal cord is just long enough to go from the audio output to the ear speakers, without restricting a full range of head movement in all directions and for all riding positions, including riding while standing up. Some riders like to have the ear speaker cords end at mid-chest, and then use a separate stretch coil cord to reach the audio output source. The parts and tools needed (solder, heat shrink, jacks, plugs, etc...) to make these modifications are available at most technical electronics shops (Radio Shack, etc...).
* Suggested by Robert Pierson

Warning! Some of these devices block out ambient sounds important for safe riding. Do not use where other road users may be present. Some of these devices may not be legal for road use in your area. Check local laws before using. If in doubt about safe usage, do not use. We do not encourage use of some of these items on public roads. Some items may interfere with your ability to hear stuff that is going on around you, and that stuff may hurt or kill you.