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Fork Rebuild
This information was taken from a series of posts by Bill Royal, STOC
1137 -
http://www.silverstreakst.net/. They are largely unedited -
only reformatted.
I finally got a stretch of time between riding events, and family
visits, and other maintenance that might allow it and even the fork tool
kit that John O put together was available! EGADS - no more excuses.
So after a weekend of riding and a Monday back to work, I start. Easy
enough to begin with. Remove the handle bar trim plastic and the front
fender - the only plastic necessary to remove for this procedure.
Then, the brake calipers, hanging them carefully from the fairing with
cable ties, and finally, off with the front wheel. Not bad really, about
an hours worth of work and I called it a night.
Next night I am back at it, this time with my air tools and the 6mm hex
bit (extra long from John's kit) and a couple squeezes from the trigger
and the right fork's lower allen screw cracks open - yahoo! So it's off
to the left fork and that's where my first bump in the road occurs.
Applying the same technique as I did on the right side, but this time
the result is the allen bit stripping the head of the screw - oh well,
at least I was prepared (once again thanks to John O's advice) as I had
ordered a pair of new screws along with the recommended replacement
washers. So I leave this part for now and move up to the fork caps. Once
again, the right fork is no problem. After loosening the upper fork
clamp screws, the right fork cap loosens as expected with just my hand
socket wrench. I move over to the left one and damn, it just isn't
budging! I double check the clamp screw to be sure I wasn't dreaming
when I thought I loosened it, and no, it's plenty loose. So out comes
the 2 ft. breaker bar - this should do it. Damn! Still won't
budge. Now I am getting concerned... I had this left fork off about a
year ago when it leaked and rather than tackle the pair at the time I
took the fork up to my local dealer and had them replace the seals. So
they did that and two days later, I simply re-installed the fork, never
feeling the need to check the cap or anything else on that fork for that
matter. So my final attempt is with my 1/2 in drive air wrench through
the 3/8 reducer to fit John O's custom made fork cap hex drive socket.
Ratta-tat-tat-tat - not a budge. Another burst again - still no budge. I
triple check my upper pinch bolt - yes if I loosen it any more it will
fall out. So, Ratta-tat-tat-tat-tat-tat - it seems to maybe be moving
ever so slightly, but as I look closer I see that the cap itself hasn't
moved at all - it's the drive reducer now deformed to about 45 degrees
of it's normal orientation. This sucked it on there and I'm obviously
not gonna get it off. I am pretty pissed at this point, already cursing
the dealer 'cause I know THEY were the last ones to remove and replace
this fork cap... The torque spec is just 14 ft-lbs!
So I give up for the night, resigned to the fact that I NEED to bring
this fork to the dealer and am mentally preparing for the words that I
will need to get them to understand that they should be removing the cap
for gratis labor and that IF the threads are stripped it's gonna be on
THEM! Well, that plan is going to have me delayed 4 more days until the
weekend because that's the first I can make it in person to the dealer.
Rather than wait, I recruit my lovely better half to run the one fork up
there and I prepare her with the details so she can at least state the
case. So Thurs AM she runs the left fork up to the dealer, brings it in
and hands it to the owner and give him the story.
He takes it out back, and had his mechanics take a crack at it whilst he
returns up front to conduct some other business. This is all important
facts as will become apparent in a little bit... About 10 minutes go by
and the mechanic shows up in front of the parts desk with the fork cap
loosened. - No charge. When I get home that night I an very greatly
relieved to see that the threads are fine - I can only begin to imagine
what torque they put that cap on to in the first place but I know for
sure it's WAY beyond 14 ft-lbs!
So that night is billiards night and I almost never work on a Friday
night so all is status quo until that Saturday. Then I'm at it
disassembling the right fork. It's pretty straight forward, albeit a bit
messy. That fork oil is very slippery and it just runs on anything it
touches. I get the fork apart and let the pieces "drain" into a basin
lined with towels to absorb the oil. Then, it's on to my next challenge
- drilling out the right fork's stripped lower cap screw. After a
bit of guessing I settle on a 3/8 drill bit and chuck it up. I lay the
fork on the work bench with the head butted up against the wall so I can
give good pressure on the bit as I drill. I wind it up and start
drilling. I keep checking as I am worried about drilling too far and
perhaps drilling into the fork base itself. Every 30-40 second of
drilling and I pull it out and blow the shavings away with compressed
air. I am getting what I think it close to being too deep and it still
hasn't come loose yet, so I decide to switch to a smaller bit. One that
I am sure won't enlarge the fork hole if I go too deep. A minute or two
more with that and I can see that I am clearly deeper than the surface
of the fork, so I go back to the 3/8 bit and with a final 20 second spin
of that I feel the bolt come free. I pull out the bit ant the head of
the screw falls out on the floor. I tip the fork up and despite having
drained it for some time prior to this it's still dripping fork oil all
over the place! Anyway, long story short, I now have the bolt out and it
doesn't appear that I'm munged the fork base at all in the process. Of
course the copper washer is still stuck to the fork and it takes another
few minutes of careful digging and prying with various implements to
dislodge it but eventually it too comes off. I note that the washer, as
well as the threads on the bolt appear to have some sort of clear
looking hardened "goop" on them and I wonder if that isn't factory
applied thread sealant run amok attributing to the excessive
recalcitrance of the bolt. Sure am glad I took John O's advice and
ordered the bolts! That all consumes about a half a days labor and
I have other chores to attend to so that's it for this Saturday.
Sunday, I remove the parts from the drip pan, and wipe them all clean
and try to clean up the various spills and clean up the tools. Then,
it's on to assembly. I take the right fork first (hoping to have
continued success with right first!) and it all goes together pretty
well. I do use a very small amount of blue locktite on the lower allen
bolt as I hope to avoid any problems removing it in the future. Then the
new slider on the lower end of the fork tube and the tube go in place.
Now to assemble the upper busing. John's tool takes a little adjusting
and the bushing goes in about half way with a few gentle taps of the
hammer against a piece of 2/4 used to protect the end of the PVC Pipe
tool. Then I reverse the tool and use the other end to drive it in a bit
more, and then finally the last 1/4 in or so I used a long rather large
sized flat head screw drive. John's kit does contain a custom made
bronze drift but my big paws find it a bit tedious to use so I opt for
the screwdriver. I am careful to go slow and not scratch the fork tubes,
and it takes a few taps at each of the
4 90 degree compass points to fully seat the busing. Next is the fork
seals - the only concerns here is proper orientation and not damaging
them as you push them down over the tubes. The manual suggests applying
tape over the rim of the tubes, but I didn't do that and found it not a
problem to carefully push them down evenly over the tubes with out
damage. Of course, a generous wiping with fork oil on each of these part
helped a lot. I also ordered and there for replace the spring clips that
hold the seals in place though I probably could have reused the
originals. Finally the dust seals slide on and using the pvc tool drive
them home and we're almost done.
This is the point where you fill the forks with oil and set the level.
I had no idea of exactly how much to fill with in the first place so I
just dumped a little less than half the one container I had in. That
turned out to be a fair bit more than necessary because when I went in
the "turkey baster" it quickly filled the lower tube, then the upper
tube and finally into the bulb itself where it proceeded to start
leaking like a sieve all over the place. Did I mention to NOT attempt
this in the kitchen? Fortunately I was in the garage so no harm, no
foul. I clean up the mess and try again, this time only getting a bit
more oil out before I can tell I've got the proper level set.
I set this fork aside and set upon the recalcitrant left fork. For all
the trouble it gave me earlier, it goes together easily and it's not
long before I have it all rebuilt and filled with oil. Now for the fun
part. I set the springs into each of the forks and it's only then that I
realize these puppies are a fair bit longer then the stockers! I'm
thinking it's gonna be a B$%*& to get them compressed. I soon see that
there is just NO WAY to do the rest of this alone so I call up one of my
buddies from down the block and he comes over to give me a hand. I also
take a Bud break.
We start with the right fork now. Together with him holding the fork
steady and holding the "rod tool" to hold the damper up and ready to
insert the keeper I use a pair of flat tire irons through the spring
coils to compress them down until he can insert the keeper (this is the
right fork). He has to let go of the damper for a sec to do this since
ho too only has two hands but he is able to get it in quickly and we're
just about done here. Push the damper all the way down, remove the tool
and now to put the cap on. Once again, he steadies the fork by holding
the tube while I use the custom made cap allen socket as I begin to get
the threads engaged he also turns the tube counter-clockwise thus
speeding up the thread in and voila - it comes together like a charm.
The left fork is next, and even though it has a longer spacer it's still
easier overall to get together.
A short note about spacers. The Progressive manual calls for cutting
down the factory spacer on the left leg to 3.25 in. and doing away with
the shorter one in the right leg all together. But seeing as I am such
"big" boy these days (~275 or so), and having read about someone else
who went with a larger spacer before and was happy with it I decide to
go that route. The recommendation is to use Sched 40 PVC pipe, 1 in.
diameter. What no one has mentioned to date is how to cut that so that
it's square. There are the "ring around cutters that will cut a nice
square pipe cut, but the small ones say up to 1 in. So I buy one and get
it home only to find that 1" pipe means the ID of the pipe. The OD of
the pipe is more like 1 1/4 ", or just over the 1 1/8 capacity of the
cutters. The larger cutters of this type run about $30 so no way I'm
going that route. The ratchet knife cutter is affordable at $9 but it
will NOT cut a nice straight cut! So, on my third trip to the Home Depot
I am looking around and I spy the 3/4 Sched 40 couples - they are
exactly the correct OD, and exactly 2 in long each. I hadn't yet decided
on exactly what length spacer I was going with but two of these puppies
together made 4 " or just 3/4 longer than the recommended length. Since
I already heard that someone had gone 5/8 longer and been happy, I
decided that 3/4 over was gonna work just fine for me. Now, that meant I
still needed to cut a 3/4 spacer for the right fork but I used the knife
cutter and then dremeled the crooked cut even to get the right
dimension. So if you go this route be prepared,. Yes you can saw it off
but it's still tricky to get a nice even cut and it's messy but that can
also be made to work. Also note that using longer spacers does add to
the woes of assembling the caps on but I was able to do so in spite of
this.
So, that wraps up another night. It's off to work for me on Monday and
that night I plan to put the forks back onto the bike and be done.
Well, not so fast... I get the forks back on the bike and the wheel back
on and am in the process of bolting the calipers back on when I hit yet
another snag. Remember that wayward left fork I had to send up to the
dealer to remove the #$%(*)*@^ fork cap off? Well there's a little
collar bushing that sets inside of a needle bearing that is where the
upper caliper bolt for the left caliper screws through. As I am
attempting to torque that allen head cap screw in it feels like I may
have stripped the threads! No way _ I am set at only half the spec'd
torque. Closer inspection shows that the collar that the bolt torques
down on is missing. I look all over the garage for it and it's nowhere.
I clean up the work bench cleaner than it=92s been since I moved in and
still no luck... Now that part was on that fork when I removed it and if
it's not anywhere in the garage it HAS to be only two other places.
Either my honey's car or at the dealers. Well a thorough search of the
car turns up noting... CRAP! Another run in with the dealer is in the
offing. Next day I call up there and get the owner on the horn. I tell
him about the missing part and he immediately denies it's anywhere in
his shop. He swears to me that when my bride handed him the fork, he
walked it out back and "held it in my hands" while the mechanic put the
air wrench to it and that was it. It loosens up and he walks it back out
to my honey. Bull pucky I am thinking. I already KNOW that's a crock.
For one thing, she was very clear that he came back out and waited on
customers and the mechanic brought it back out in about 10 minutes.
Secondly there is NO WAY he "held it in his hands" when I busted off an
adapter and it still hadn't budged. Give me a break! Lying B)#&%)* I can
see this is going nowhere so and OF COURSE they do not have the part in
stock so I have nothing to do nut order up a new one and wait for it...
OK, fast forward 4 more days - I finally have the part in hand and the
rest of the assembly goes as it should The bike is back together and I
take it for a test spin. It feels NICE And no noise (squeaking) from the
forks as I had heard some say they experienced. Only after a full day's
ride will I really know the verdict however. The next day I get in a
nice 300 mile ride through the back roads of Florida that even most of
the natives don't know about. Man the ride is sweeeeet. Gone is the
vertical oscillations I had as if I was riding down a washboard even
when I was on smooth pavement. When I enter a turn the forks take their
"set" and stay planed unlike before when I could feel them set and then
unload a bit. I have not measured sag yet, but I can tell it's raised
some by how I don't have to raise the bike so far toward vertical to get
it off the side stand. Overall I am way more than pleased with the
results. Only regret is not doing them earlier!
So that's the saga of my fork rebuild. Only thing left to do now is
return the kit to John Oosterhuis with my sincerest of thanks and
encourage anyone out there who is thinking about it to go for it. I am
kinda thinking that if you ST has anywhere near 100K on it (mine's an
104,500) and especially if you still have the stock springs, and even
more so if you are not the average japanese weight - you probably NEED
to do them!
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