Fork Question

[Toolmaker Tim]

Haven't been around for a bit, but decided to tear into the 79SF and get back on the road. Ordered a set of SS brake lines and have run into a couple issues. First one is the stock banjo bolt has the hole too close together/ the banjo's are thicker than stock. Solutions or comment as to whether this is an issue anyone else has seen? Second issue concerns a leaking fork seal. The left side brake disc and pad are soaked with oil, so they will need to be cleaned up and maybe the pad s replaced. While I was looking over the fork tubes before rushing into anything I realized the fork tops are not the same distance from the upper triple tree. Left measures .195 above the triple tree and the right tube top measures .156 above the TT. This may or may not be an issue, but the fact they are not even bugs me. Plus it makes the caps to the air valves VERY close to the handlebars. I had no plans to move the position of the tubes while changing the fork seals, and I haven't removed the front axle or fender so I won't lose fork alignment, I had planned to work on one side at a time so I kept a point of reference to work back to. With the forks already uneven, this throws my plans into disarray. Willing to listen to any advice.

[crazy steve]

...I had no plans to move the position of the tubes while changing the fork seals, and I haven't removed the front axle or fender so I won't lose fork alignment, I had planned to work on one side at a time so I kept a point of reference to work back to. With the forks already uneven, this throws my plans into disarray. Willing to listen to any advice.

There really isn't any 'fork alignment' to lose; particularly if the tops are uneven. Unless you have some bent components and the PO has forced/misaligned bits to compensate for it....

To realign the forks is simple; if you're replacing fork seals, pull both forks off the bike and rebuild them. Reassemble in this order:

1. Loosen the stem bolt on the top tree so it can rotate, and all the pinch bolts.
2. Install the forks in the trees, adjusting 'height' in the trees so the forks are even at the top. How much they are out of the top tree is up to you; I'd make sure the cap clears the tree, you can make minor adjustments in bike height by changing this. Torque the lower tree pinch bolts now. This will 'pull' the forks into alignment in the forks.
3. Lightly snug the stem bolt, then torque the upper tree pinch bolts.
4. Torque the stem bolt.
5. Install the wheel/axle. Torque the axle nut (but not the axle pinch bolt).
6. Check rotor centering in the fork slots. It should be centered on the axle nut side; on the pinch bolt side, push/pull the fork until the rotor is centered, then torque the pinch bolt.
7. Reinstall the brakes, fender, and the fork brace if fitted. That's it!

Doing it like this will allow you to check both forks for matched components, as well as checking your tubes for straightness against each other. This is a good way to 're-set' the forks after a minor mishap too. If you have issues with alignment after doing this, then something is bent. This would also be a good time to look at the stem/neck bearings while you have it apart.

As to the banjo bolt, if it's long enough to safely retain both lines, just drill another hole (90 degrees to existing) where it needs to be.

[mack]

What Steve said

Plus check your spring length at the same time and cut a PVC spacer if required. I also replace the o rings in the cap. For the time it takes why not.

[TopCatGr58]

Hey Tim,

Welcome back! As long as you have ample number of threads into the caliper and master cylinder with the banjo bolts, then you shouldn't have any problems. Just checked what Steve said, guess you're talking about where the 2 lines are combined at the top of the forks junction. I guess you could drill a new hole like he said, otherwise will just need to hit your local bike shop and pick up a longer bolt designed for the wider banjo joints?

Also you'll find it much easier to work on the forks with them OFF the bike. It wasn't very hard to get them out once I got the TT clamp bolts loosened, however the lower tree was squeezing quite tightly, I tapped a flatblade screwdriver into the gap to help hold it apart a little more so the tube would slide down/out of the TT without fighting it so much!

T.C.

[Toolmaker Tim]

Ok, guess I was over thinking things. Thank you Steve, mack and TC.

[Toolmaker Tim]

Beer Mechanics

Got home from work last night, grabbed a beer and headed out to the garage to take the forks apart. Everything went well until I loosened the bottom bolts. Obviously what they are threaded into is spinning, cause they ain't coming out. Mr Clymer was no help. What next? I suppose I could jam something in to the fork to stop the spinning part, I'm guessing the damper rod, but I'd rather learn the right way and not have to buy new parts.

[mack]

You have

To crack those ones at the bottom loose before you remove the caps and springs. Put them back together and then try the bolts again.Before you do that though mark the tubes and caps where the thread starts to engage each other. It will save you a lot struggling as getting them back together under compression can be a chore.

[bikerphil]

Tim, if you are working on Standard forks, a simple tool can be made to remove the bolt. If you have Special forks, you can use the end of a broomstick pressing against the ground with the fork upside down pressing your weight against it. An air impact driver if available may do the job without doing any of the above methods. Putting the cap and spring back in may also do the job and using air impact will greatly increase your chances of this method succeeding.

[DGXSER]

Tim, the method I use for that is to put my hand at the junction of the upper and lower forks, use a couple fingers wrapped around the bottom portion and a couple around the upper tube, sliding/pulling on the upper tube to create the friction needed to stop that camper from spinning. It really does not take alot of force, you do have to re-grip every couple turns or so though.

[Toolmaker Tim]

Ok, it sounds like I have 3 or 4 different methods to try. Plan to spend some quality time working on the bike this weekend. Wish me luck. Thank you for the help.

[fredintoon]

Hi Tim,
you shoulda pulled them first but if you don't want to do a temporary reassembly try whizzing those bolts out with an air wrench, the innards' own inertia should be enough to hold them still.

[Toolmaker Tim]

Broomhandle

Broomhandle trick worked like a charm. After much cusing and sweating I got the old seals out. The guy in the Clymers manual said to use a blunt screwdriver. I'd like to use one on him. Need to clean up the dings on the TOP of the sliders and clean everything up good before reassembly. Still need to look for a longer bango bolt, even though the one I have works. Just being picky. Need to rebuild the rear master cylinder before I put the new stainless line on, then I can drop kick this XJ master into the dumpster. Maybe I can go riding before the summer is over.

[bikerphil]

Broomhandle trick worked like a charm. After much cusing and sweating I got the old seals out. The guy in the Clymers manual said to use a blunt screwdriver. I'd like to use one on him.

Glad you got them apart/fixed. Next time might want to use one of these automotive seal pullers, works like a champ...

[Rasputin]

Any brake part supplier will have an assortment of Banjo bolts. Simply measure the thickness of your lines (dont forget the copper washers) and go ask. Last time I paid about 2 bucks for a double banjo bolt to fit the custom lines I installed. Drilling a banjo bolt is only asking for trouble in my opinion even though it would definetly work.

[Toolmaker Tim]

Uh Oh Boo Boo?

Ok, got the fork tubes apart, cleaned out about a 1/2" of garbage out of the bottom of the sliders and grabbed the seals to install them. I noticed that the bottom of the seals had a metal ring that went between the slider seal seat and the seals. It came out in the pry fest while taking out the seals. The new seals have no metal ring on the bottom of them, sooooo.... I'm thinking I made an error in prying everything out. If so it's not the end of the world cause, I can always machine up a new pair pretty quickly. The bottom line here is do I need them in the sliders before installing the seals or not?