Wednesday, December 05, 2007

Snow? Freehub service, FSA RD400 wheelset

Winter is here and we saw a few inches of snow at the shop today.
This is looking out towards the entrance for the shop. Through that section of trees is a slice of heaven I call Starbucks. That's Josh's Subie.
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And now back to bike stuff.

I have been meaning to do a posting on the servicing on a freehub/rear hub. I explained on a prev posting about the Shimano WH-600 f/h service. I performed a service on a wheel that belonged to one of the racers for the team that the shop supports. He is riding the FSA RD-400 wheelset. A nice performing set of hoops, good weight and super affordable. Barry started placing better in his Cat upon ditching his sponsors hoops and rolling on these that I ordered for him, hmmm.

This is a basic service where I won't be removing the axle or the bearings of the hub or freehub. They are removable cartridge type and ceramic versions are available.

Here we go. I apologize in advance as I took these pix with my camera phone which is CRAP! But it was better than reading another text-laden posting by yours truly.

Tools needed.
-Compressed air
-Flat blade screwdriver 1/4in.
-Chain whip (SR-2)
-Large adj wrench
-Freewheel removal tool (Park FW-5)
-Metal Prep cleaner
-Phil's Tenacious Lube (the best shiat in the world)
-Shop rags/paper towels
-5mm t-handle hex wrench or equiv.
-Dental pick

Remove the cassette in the usual fashion.

With two 5mm allen wrenches in either end of the hub, break the alloy end cap loose. Normal threading applies here, left handed threads. Remove the drive side end cap and set it aside. Whenever disassembling hubs it's good practice to be consistent with the wheel's orientation. At this work bench I place the wheel upright on edge and support it between my stomach and the back of the work bench, freehub on the right side. I do the same orientation with wheels in the truing stand too. Lay the disassembled parts on the corresponding sides of the wheel.
Now slowly turn the freehub counterclockwise while pulling gently upwards. Gently? Ya that. The first time you don't and might be servicing a Mavic Freehub (they are Nazis to deal with for getting parts...) and pull up too quickly, the freehub paws with spring out quickly and across the shop. Maybe then loosing the small ball point pen looking springs as well. Phuk!
Inspect the paws to see if there is anything out of the norm. What to look for? Small animals and an old potato chip? If the f/h has been operating fine, nothing. If it's been skipping and possibly the teeth are hanging up, time to clean it. This is the first service that was performed on this particular hub.
Remove the hub sealing ring first and set it aside oriented the same way it was installed. Remove the spring that surrounds the body's base and that which retains the 3 freehub paws.
With everything apart, spray the freehub body really well with the Clean Streak and set side for a minute. Spray some more on the clean shop rag and wipe down the paws and seal ring. Wipe down the freehub body and the 3 cavities that the paws rest within. Use a bit of compressed air to expel the remaining dirt and cleaner. Spray CS and wipe if necessary.
Do the same cleaning process for the ratchet ring that that the freehub sits within. It should sparkle as above. Or close to it depending on you level of OCD. I use the flatblade screwdriver and a rag to get into the corners of the teeth inside of the ratchet ring. Wipe clean the axle/bearing contact area. Wipe down the sealing ring too, retaining the orientation of it on the bench.

As you can figure out, 3 paws and a lot of rotation engagement makes for a more responsive freehub. More superior to Shimanos large degree of engagement (10deg?) on their cartridge system for freehubs. This FSA freehub can be swapped out with a Campagnolo style for around 70 bux.

Use a couple of drops of Phil's in the resting spots of the paws. Reassemble the paws carefully. One end of the paw has a larger 'shoulder' and rests into the freehub paw/cavity while the other end is smaller and makes contact inside of the hub. Install the spring with the dental pick and be sure to locate the start of the spring wire against the post that is sticking out of the channel that houses the spring. Got that?

Slide the sealing ring on. Wipe some lube with your finger tip on the sealing ring. One side of the ring's contact surface has a 45deg chamfer, that is the side to be facing down into the hub upon reassembly.

Apply some of Phil's around the paw/sealing ring region. Don't soak it but be sure to cover it. At this time use your finger to push the paws a few times to make sure everything is seated and snapping in and out as it should.
Apply a film of Phil's around the circumference of the ratchet ring. Again, don't flood it but be sure to have a least 20-30 drops down inside.
Apply a bit of Phil's onto the axle/bearing surface. Carefully slide the freehub onto the shaft. When you just start to make contacting at the hub/paw area, slowly turn the freehub counterclockwise while slowing pressing downward. The freehub should engage without much resistance into the ratchet ring.

Use the two 5mm hexs and install the driveside alloy end cap. Install the cassette and BE SURE TO USE THE CHAIN WHIP TO STABILIZE THE CASSETTE when installing it. If you're unsure of what I mean, while facing the cassette, run the whip handle on the left side of the cassette wrapping the whip's chain clockwise around. Location of the chain whip should be mid cassette and no bigger. Tighten to spec. I am stressing this because many bike mechanics(hacks as some are) will install the cassette with only an FR-5 and an adjustable wrench. By not taking the tightening load 100% off the freehub and onto the FR-5, you greatly stress the paws of the freehub.

The immediate thing you'll notice is that the operation of the freehub is much quieter. The noise will increase as the miles go by. I recommend this service every 5k from here on out, pending riding conditions, wet, dusty, etc.

Nuff said.
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stickboy

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