Well, so I got everything all together and she rode fine and about a block from my house I got a sudden very loud tapping but it was hard to tell where it came from. Got home and had a look and the front motor mount bolt came out. Replaced it and went for a ride today, no problem and then on the freeway again a loud tapping all of a sudden about 30 minutes into the ride. Tapping when letting off the throttle mainly. I thought the bolt I replaced had maybe come loose but it was fine. Rode around over by this giant park by my house that is under construction and no noise, I could rev it high with no noise. Took off again and suddenly again loud tapping but not really in synch with the motor or anything and would go in and out. Then it stopped and I rode home and it would come and go at various degrees of loudness. I cannot pinpoint where it is coming from while riding and it doesn't do it at idle. I am at a loss but I did just have the exhaust off, so I am thinking either an exhaust leak or possibly a lifter is going bad. I rebuilt the motor about 1500 miles ago. Thoughts? I am going to pull the exhaust later when it cools down and see what it looks like. I did get a loud backfire when I started it today as well. Something is going on, but other than the loud inconsistent tapping at times it seems to run and idle fine.

 

Very interesting, please keep us informed. You're clearly a superior mechanic, so I'm sure you'll track it down. Good luck!


John

 

I think it's a worst case scenario. I removed the forward pegs as I thought maybe the exhaust was hitting the pegs. I don't use them anyway as I prefer to use the mids but it was nice to have both. Took it for a ride and once it got up to temp the tapping started only on deceleration then it became constant and did match the rpm and I could now hear it at idle. I got off the bike and gave a listen and bam....sounds like it's coming from the bottom end. Well, everything seemed good down there when I had it apart so I didn't rebuild it but oh well, looks like the motor is coming out again and getting torn down to see what is going on. I'm out of town this weekend so I guess I will get it apart next weekend. At least it didn't give up the ghost so it should be serviceable whatever it is. We shall see.

 

Ugh! What a bummer. I think I've only read about a couple lower end problems on a Sportster being posted over the years. Kind of amazing. I think the 2004-06 cranks may have had issues, but it seems like most all are pretty solid. Seems like you caught any problem well before it became catastrophic.

John

 

Ya, one of the downsides of no gauges is no odometer so when I bought it I had no idea how many miles it had on it. Should have just rebuilt it when I had it apart. Oh well.

 

Just saw a video of a bad lifter and it sounded pretty much like my bike sounds so maybe it's just a lifter. New S&S lifters when I did the rebuild but perhaps one bit the dust. I guess I'll find out soon enough.

 

Bent pushrod or something sounds way better than rod, good luck with it

 

My only other thought would be to check the oil pressure before you tear it down

 

I pulled the dipstick and there was a little pressure when I popped it off and oil looked to be flowing freely. The bike never got hot or anything. Based on the dipstick gauge everything seemed normal.

A couple of times recently the bike has backfired when I tried to start it. And a couple of times it has just died for no reason and then wouldn't crank over right away. Yesterday it backfired out the carb pretty good and died. This is also why I was thinking it was the lifters as maybe the valves are not opening/closing properly at times causing it to backfire/die.

After seeing the video I am hopeful it is a lifter and not a rod. Only one way to find out. At least I can get at the pushrods and lifters without pulling the heads and save me the cost of new head gaskets if it is in fact a lifter.

 

Now the bike won't even run. Starts then just slowly dies with the choke on. I don't think I will start it again. I might be able to pull it apart tomorrow afternoon when I get back.