6.04. Front Forks

From 650wiki

Jump to: navigation, search

< Back to 6. Chassis

Steering Headset Tapered Roller Bearing Installation

Remove the mirrors and handle bar controls from the handlebars. Remove the handlebars and set them aside. Removal of the speedo and tach is recommended, although I got by without it. Remove the bolt that holds the top triple tree bracket. Loosen the three top triple tree clamps allowing the removal of the top triple tree bracket.

When I did the job, I had the front tire and brake caliper removed. This made the fork assembly considerably lighter and I would highly recommend it. Either way, use a jack (or similar) to support the bike on the centerstand and hold the front end off the ground. The headset is attached using two nuts locked together. They are not hex nuts. I used a brass drift to loosen the top nut and removed both nuts allowing the fork assembly to drop away from the frame. I pulled the headlight and triple tree spacer assembly free and supported it from the bike frame with a rope.

Once the fork assembly is free from the frame, the old ball bearings will fall away - usually all around the garage or other work area. The top ball bearing race comes off easily once the nuts are removed. The three remaining races are pressed in and will need to be driven off. Two races are in the frame and can easily be driven free using a punch or a drift. The last race (of the four) is pressed on to the fork assembly. I used a pair of old 3/16" standard screwdrivers to move the race 1/2" up the shaft until I could get my brass drift in there to free the race completly. Discard the four original races.

Like the old races, three of the four new races will need to be pressed onto the bike. The upper and lower outer races will need to be driven into the bike frame. The lower bearing (and inner race) will need to be driven onto the steering shaft. I found my brass drift (inherited from my grandfather) to be invaluable. Others have used the old races as a buffer.

Be sure to grease the new bearings well. Once the new races are installed, reassemble in the same order as disassembly.

(Matt Q. in Detroit)

Some additional info is at 6.15._Seals_and_Bearings

Fork Seal Removal

I saw an interesting way to pop the fork seals out without dissassembling the leg. Unfortunetly I can't give the credit for this ingenious method but it is similar to a bearing removal method that is popular. You fill the leg to the top with oil so there is no air to compress. Screw on the top cap so the oil is trapped. Use a long (12 feet) 4x4 as a lever with one end under a heavy deck, 4x4 over the upright fork close to the deck and push down on the 4x4 to raise the seal on the leg. After the seal blows there will be a mess so put the leg in a pan before it blows.

That isn't a very good description. I hope you can find the picture I'm referencing. The 4x4 is a lever trying to lift a heavy object (deck). The fork is the fulcrum. Anyhow the method is so clever I may try it just because.

Tom Graham

The pics to which Tom refers: Hyrdraulic Oil Bomb

Hi Tom, I also saw that photo sequence, it looked so neat and easy that I had to give it a go.

Near tore the top off my deck & ruptured myself besides before going back to the usual method.

If only they'd have reminded me to dig all the crud out to find and remove the little wire circlip that holds the seal in I betcha it'd have worked a treat.

Fred Hill, S'toon.


Personal tools