Purchased a '95 Ultra about 4 months ago. Cosmetically, it looks to be in great shape. Don't know for sure about the mileage, it's showing only 18,000, but could be 118,000. Bike runs and shifts fine. The only thing I have noticed is that I hear a knock in the engine when I first start it up, but only when it has sat for a week or more. Usually goes away after about a minute. It doesn't sound like the motor is coming apart, just a noticeable knock/tap. It doesn't do it if the bike has only sat for a couple of days, only after sitting for a week or so do I notice it. It always goes away as the bike starts to warm up, and I never notice a knock while riding, just at startup. Oil level is full, HD 20W50. Any ideas what I'm hearing? Thanks,
Kenny.

 

It could be the lifters bleeding down if they're hydraulic but that would create more of a tap than a knock.

 

It's a lifter bleeding down... no, they shouldn't do that but it happens once in a while. Try a quart of Marvel Mystery Oil and if it doesn't go away within a couple hundred miles, replacing the lifter(s) is the next step.

 

You see a lot of mid '90s Evo's with no/low miles on em so it could be only 18,000 on it. Not sure if your '95 had the "B" lifters in them, I think it may have been '96 or '97 when they upgraded to the new lifters, with 18,000 and 15 yrs it would be just about time to replace them, the "A" lifter had a life span of about 25,000.

 

What are other symptoms of worn lifters? I have around 55k miles on my present lifters (full rebuild 55k ago). If they only last around 25k or so the I am overdue.

 

They can last forever. Post #1 perfectly describes one that either has a warped or worn plate in the hydraulc portion, possibly gunk that may clean out with the above mentioned oil or a broken internal spring. (they're tiny)

Bad roller bearings can make a rattling/scraping/grinding sound a lot like a cam bearing will. And sometimes if the bearings go or sieze, it'll sound like a marble in a clothes dryer.

You read and hear a lot about lifter failure but considering the vast number that are out there running, the failure rate is almost not worth mentioning, percentage-wise...