1993 harley davidson when u get around 3000 rpm i hear a rattle i think in the top end it is louder when i let off on the gas

Disconnect the stator plug from the regulator. Have your meter in Volts AC. Start the bike and watch the meter readings. typical output is 25 volts AC per 1000 rpm. So at 1000 rpm it should read around 25 VAC. At 2000 rpm it should read around 50 VAC. and finally 3000 rpm should produce around 75 VAC. Could be a little lower which is common.

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You must be talking about the anti-rattle spring. I do not know how to explain to you how this spring goes back on. Go to this site and it will show you the spring but you'll still have to figure out how it goes on. You may have to look at another Softail to see how it goes on. The brakes will work without the spring on there but the pads may rattle.
http://www.bikebandit.com/1993-harley-davidson-flstf/o/m1215#sch147081

Good Luck
Steve

Steve, when is the last time you adjusted your primary chain? If the chain gets too loose, you'll hear a rattle like that when you let off on the gas. If you pull in the clutch, you must let off on the gas to keep the engine from over revving. This is about the only thing I know of that could be causing the problem.

But, just to be sure, I'd drain the primary case and remove the outer primary cover. Disconnect the battery, remove anything that might be in the way. You'll have to remove the oval shaped inspection cover as well. Remove all the bolts and take the outer primary off. Then, you can adjust the chain easily. Adjust it so you have between 5/8" and 7/8" up and down play in the middle of the top run of the chain. Look on the inside of the primary underneath the top in the front at the bolt hole. You can see if the chain has been hitting there by the marks on the underside of the inner primary.

I hope this helps.

Good Luck
steve

I'd wait for the dealership. If you go messing with it, they can claim that you did something that voided any warranty the bike may have had. Let them fix it. You'll be better off that way.

Good Luck
Steve

That rattle if its a piston probably is the piston pin.If your piston were making the noise it would get louder and lock up sooner or later I would not run it until its fixed it will tear up your motor.

How many miles on the engine? Are all the tappets rattling. If all the tappets are rattling, you don't have any oil pressure. If only one is making a loud noise, you've probably lost a roller on the end of one of the tappets. I think a '93 model was one of the engines that had the cheap INA inner cam bearing. Previous models had the Torrington bearing and after '94, they went back to that bearing. I could be anything.
But, it it sounds good below and above this RPM range, it's probably motor mounts. The FXR had the small rubber engine mounts. Check the front one first as it's fairly simple to check. The rear engine mounts are on the through bolt that holds the rear of the transmission and swingarm in. You have to pull the swingarm out to replace these.
Look for something loose first and then move to more complicated things.

Here is a link to the aftermarket service manual.>>

http://sunnymeadcycles.com/files/1966-84_Shovels_Aftermarket_Service.pdf

Start by checking you're stator output, Put a meter on it in VAC ( Volts AC ) on the 2 wires coming out of the case ( on the left side of the bike ) run the bike General rule of thumb is 25 VAC for every 3000 rpm. ex: 25 @ 3000, 50 @ 4000, 75 @ 3000. On the older bikes as long as you're around 65 and up @ 3000 you should be good.

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Sounds like detonation ( aka engine knock ), Switch to premium gas. If the knocking continues after the first tank of premium then go to the dealer and ask for spark plugs one heat range colder than the stock plug for your bike. This should fix the problem.
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