Classic Motorcycle Build

Norton Commando Remove Fork Tubes

Article and Pictures by Mark Trotta

Although the most common reason for removal is to replace leaking seals, the fork tubes on this 1974 Commando were badly pitted from years of sitting and needed to be replaced.

Norton Commando restoration

This article details fork tube removal on 1972 and later Commando models.

To read about how to disassemble forks click here.

To read about how to assemble forks click here.

Getting Started

Removing the tank prevents accidental scratching, plus a gives you little more working room.

motorcycle gas tank bare metal

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Brake Caliper and Master Cylinder

Disconnect the steel brake line, then remove caliper from fork leg.

motorcycle brake caliper

This caliper was bone dry, so there was no worry about leaking brake fluid!

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Headlamp Removal

On each side of the headlamp is a bolt, washer, and spacer, which go through the left and right brackets.

motorcycle front forks removal

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Prop Up Front of Bike

The front end needs to be propped up just enough so the wheel may be removed.

Norton Commando 850 Roadster

There are several options here, most common being a small floor jack under the engine.

motorcycle front wheel

Seeing as this bike was already half-stripped, it was light enough to lift up by the forks and rest on a piece of wood on a cinder block.

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Checking For Neck Play

With the front wheel off the ground, now's a good time to check if the steering bearings need replacement. In a crouching position over the front wheel, grab the forks, then push and pull forward and back. Even the slightest amount of play should be looked into. Also check side to side movement for any binding.

If you're going to be replacing neck bearings, the master cylinder and handlebars will need to come off.

Commando 850 remove handlebars

A 7/32" Allen key is required to remove the handlebars.

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Front Wheel Removal

On the bottom of the right-side fork, remove the 5/16 x 1-1/4" pinch bolt. The right-side axle nut requires a 15/16" socket. The axle can be tapped through from the right side with a soft mallet.

An alternative way is to slip a large screwdriver through the left-side axle, grab the screwdriver with both hands, then twist and pull the axle out.

Commando 850 front wheel removal

Front Axle Removal

Front Fender

Although you can remove it at any point, it's easier to remove the fender with the front wheel off.

Dunlop K81 Roadmaster TT100

There are four nuts (3/16 Whitworth), two on each side, that hold the fender onto the sliders. The two bolts that hold the fender stays to the fork sliders are 1/4 Whitworth.

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Pinch Bolts

On each side of the lower fork bracket are recessed Allen bolts. You'll need an 8mm or 5/16" Allen key to remove them.

remove front forks Commando

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Fork Tube Removal

With a 33mm or a 3/4 Whitworth socket, unscrew the big top nuts. You will notice that they have internal and external threads. The fork damper rod screws into the bottom, and the external threads screw into the top of the stanchions.

Separate Damper Rod From Top Nut

With the fork springs exposed, unscrew and remove the top nut from the damper rod. A thin open-end wrench is needed for this.

classic motorcycle restoration

This will allow for gauge cup removal.

These final steps are often the hardest.

How easy or how difficult the fork tubes come out often depends on how long the bike was sitting and how rusted they have become to the triple trees.

Re-install the top nut back into the stanchion. With a rubber mallet, smack the top of the big nut and hopefully the fork tubes will move.

If they don't move (many won't at first), try spraying with WD40, and letting them soak for a while.

If they still don't move, try a few more solid whacks with the mallet. If there's no movement - stop. Spray it with more penetrating fluid, let it soak overnight and try again tomorrow.

While removing the forks, they may get hung up on the rubber O-rings on the top and bottom of the headlamp brackets, which detach once the forks slide out of the triple trees.

Commando headlamp brackets 062028 and 062029

Left and right headlamp brackets before cleaning.

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Drain Fork Oil

One of the oil drain screws was difficult getting out. Rather than take a chance of stripping out the original 50 year-old screw, I waited until the fork was removed and laid out on the workbench, which gave an easier vantage point. A fibre washer should come off with each drain screw.

fork slider drain screw 06.0354

The old fork oil was drained out into a pan, and can be recycled with old engine oil.

vintage British motorcycle repair

Read: Front Fork Disassembly

Norton Commando replace fork seals

Read: Front Forks Overhaul

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Related Articles:

Norton Commando Build - Homepage
Norton Commando History
Engine Removal
Commando Cylinder Head Removal
Timing Cover Remove and Install
Gearbox Removal
What Are Whitworth Tools?
Norton Commando Upgrades