Poll: What do you think is the most "difficult" timing belt to service?

[road_rascal]

did they fail visual inspection at 100k miles as required per the tech manual which required the replacement?

No- the bike only had 50K on it but it was 10 years old when I did the belts. I was doing other work to it which had most of the plastic off anyways so I figured I'll just replace the belts and check the tensioner bearings.