How do I get my replacment forks back into the lower triple tree on my 1987 FLSTC (Heritage Softail Classic),?

Well, yes. The fork seals are located at the top of the fork slider un the "slide tube cap". This makes me wonder exactly what did you replace when you say that you just replaced the "fork seals". To get to these oil seals, you have to disassemble the forks tubes. Remove the front wheel and fenders. Down where you took the axle out, look up into the end of the slider and you'll see a socket head bolt, 6mm. Loosen this bolt before you take the tube out of the triple tree. Remove and repair one tube at the time. When you get the slider off the top tube, you will see a retainer ring in the top of the slider. The seal is under this ring. The new oil seals must be replace squarely in the tube. When you reassemble the tube and put it back in the triple tree, there is a specific amount of fork oil that must be added to each tube to properly refill it. You must use the "dry" quantity when refilling the fork tube because you disassembled and completely drained the tube. I'm sorry but I don't have this quantity of fork oil for this late of a model bike. I work on the earlier model bikes only.

good luck
steve

I don't have the instructions for the Softail but I do for the Dyna series bikes. I'm pretty sure it'll be the same.

Loosen the upper triple tree clamp pinch bolts and remove the upper triple tree and handlebars.

Raise the front end off the ground and loosen the fork stem bolt and allow the front fork assembly to drop down approximately 5 inches.

On the left side of the steering stem thare is a "half-moon" indentation that has been machined into to steering stem for the lock. Let the steering stem drop until this indentation is in full view.

Now, there is a set screw that holds the lock into the frame steering head. The set screw screws upward into a recess in the lock mechanism. The set screw is covered by a lead plug so that it is not easily seen or gotten to. The book says to use a scribe to remove the lead plug.

Unscrew set screw.

Insert a key into the lock and turn slightly

Wiggle and pull the lock assembly until you get it worked out far enough to get hold of the lock with a pair of pliers or something.

Rotate the steering stem slightly until the lock comes out.


Good Luck
Steve

To replace the front seals on your Heritage, you'll have to pull the windshield and the nachelle off the front of your bike. Lift the bike off the ground and remove the front wheel and fender. Then loosen the pinch bolt on the lower triple tree and take the top cap nut off at the upper triple tree. Then slide the entire fork assembly out of the steering head. Take the top plug out of the upper fork tube. There will be a large spring under this plug. When you take the spring out, there should be a tapered end on the sping. Look closely and make sure you put it back in the correct direction.

Underneath the lower fork slider where the axle goes, there is an 8mm socket head bolt. This bolt takes a special "piloted hex key" to remove it but I have gotten them out using a "brand new hex key socket" and an air wrench. The hex key socket must be brand new since the depth of the hex key socket is so shallow.

Once you have the bolt out, you can pull the fork tube out of the lower slider. The seal is in the top of the slider. Remove the snap ring and pry out the seal, Notice the direction the seal is facing. After you assemble the fork tube assembly, pour in the appropiate amount of the correct oil for a "dry" rebuild.

Reassemble that tube and do the next one. Only do one tube at the time. Don't forget to torque the pinch bolt on the lower triple tree. 25-30 foot pounds. Reinstall nachele and windshield.

Good Luck
Steve

many things can cause this ,if you change your seating postion ( lean forward / move backwards does it go away?....

front forks loose at triple tree,
new front / rear tire more aggressive tread than before,
front wheel loose,
worn head bearings,
bent rim,
loose spokes if any,
wrong tire pressures,
loose handle bars
,some new addition to change the handling of the bike , rear seat rest etc,

probably the stem nut on the top triple tree.

You have a few to choose from inside the headlight bucket.