Gen 2 Fork Disassembly - Advice required

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FJRGuy

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Pulled a fork off of my ‘Parts’ FJR to send the inner cylinder to MEM so she can have her fork repaired. Thought I cracked the torque on the lower bolt before starting to disassemble, but now it just spins the internals as I try and remove it. I had turned off the cap and drained the oil so tried reassembling the top to put the spring under compression but the lower bolt is still just spinning the internals. 
Can anyone share the trick to removing the lower bolt?

 

Auburn

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You need a 26 mm socket welded onto the end of a piece of tubing and a 3/8 socket extension welded on the the other end.  It will hold the cartridge from spinning while you are taking the bolt out and also allow you to torque the bottom bolt on reassembly.  Below is my home made one.  The tubing is 1/2" diameter.

DFE2Isl.jpg
 

 

FJRGuy

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Thanks Bryan, exactly what I was thinking, but afraid of. 🙁 I will have to make one of those for future use, but no time for my immediate need. I’ll just send the whole fork (less the spring, cap and misc internals to reduce size and shipping cost) to her and let her ‘tech’ pull it out. I believe she has a shop working on hers. 
 

Thanks Ross, saved me some time searching for something like that. This one is a stock fork. I’ll be doing the forks on your old bike and the Traxxion shocks off my NC bike at a later date. 

 

RZ350

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Just trying to recall what I did a couple years ago when rebuilding my forks with new bushings.  I did not make a special socket, I know that for sure.  I think I got lucky and the bottom screws broke loose and came out without much struggle.  During reassembly, I believe I used a PVC pipe or something similar to grab the very corners of the hex to keep it from turning.  Some specialty plumbing sockets are made this way, but have a more defined hex molded in them.  It doesn't take much to hold it while achieving the specified torque on the bottom screw because there is also friction helping you out too between the mating surfaces.  Next time, i probably won't get so lucky.  LOL

FYI - You can also make whatever size light-duty sockets you want quite simply from the proper sized thin-wall tube.  Think about the cheap spark plug wrenches that come in the OEM tools kits normally... the end of a tube is just formed into a hex shape.  The tube can be whatever length you need.

 

Auburn

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Just trying to recall what I did a couple years ago when rebuilding my forks with new bushings.  I did not make a special socket, I know that for sure.  I think I got lucky and the bottom screws broke loose and came out without much struggle.  During reassembly, I believe I used a PVC pipe or something similar to grab the very corners of the hex to keep it from turning.  Some specialty plumbing sockets are made this way, but have a more defined hex molded in them.  It doesn't take much to hold it while achieving the specified torque on the bottom screw because there is also friction helping you out too between the mating surfaces.  Next time, i probably won't get so lucky.  LOL

FYI - You can also make whatever size light-duty sockets you want quite simply from the proper sized thin-wall tube.  Think about the cheap spark plug wrenches that come in the OEM tools kits normally... the end of a tube is just formed into a hex shape.  The tube can be whatever length you need.
a 26 mm Kobalt socket at Lowes is about $6.  All told the tool costs you about $15 to make and takes about 30 minutes (not including the drive to Lowes and back).

Biggest reason to make the tool is it fits, and you don't take a chance on damaging the nut on top of the fork cartridge which I believe is about $300 to replace.

 

RZ350

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a 26 mm Kobalt socket at Lowes is about $6.  All told the tool costs you about $15 to make and takes about 30 minutes (not including the drive to Lowes and back).

Biggest reason to make the tool is it fits, and you don't take a chance on damaging the nut on top of the fork cartridge which I believe is about $300 to replace.
Agreed, the proper tools are always best, but there are always dozens of ways to accomplish a given job.  I was probably too broke after buying the special sized thin wall aluminum tube to drive the bushings back in to invest anymore in the project.  LOL

 

Mad German

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I'm looking to do my forks this fall. Is it possible to loosen the 8mm socket cap screw at the bottom of the forks BEFORE removing the cap?
 

Mad German

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Yes. And advisable too! I use a battery powered impact wrench to 'jolt' the bolt free. Hand held ratchet delivers linear power... You want and need impulses to break the fastener free.
Thanks. I've never rebuilt forks before, but I'm pretty competent with tools and really want to give this a try myself. I know some guys say it's a bear of a job, and others say it's not too bad as long as you're methodical about it and take your time. A local shop near me quoted me ~$300-350 to disassemble, clean the forks, install new seals, and fill with fresh fluid. That price doesn't include new bushings, which I'm planning on replacing since I'll have it all apart.

Thoughts?
 

RossKean

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Bushing and seal replacement - FJR Gen II

The only thing difficult is getting them apart. The slide hammer approach works great until the middle bushing gets jammed under the top one. Carefully warming the region around the top bushing with a heat gun may be beneficial.

If you look at the PDF from Mark John's sit (linked, above), you will see the biggest difficulty with reassembly is the middle bushing. When I did mine the last time, I did not install a middle bushing. This is what was recommended with the Traxxion AK-20 setup I have. Lots of people don't do the middle bushing but Yamaha thought it was necessary. So far, I have had zero issues... YMMV

Link to Mark's home page with lots of good FJR info:
 
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Auburn

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I use a map gas torch to warm the area around the middle bushing. You can get a good amount of heat in the fork leg in about 30 seconds. They usually come out with a couple of pulls on the inner tube.
 

FJR30FAN

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It was a lot easier than I expected going in with no prior experience doing forks. Give the tube a swift firm pull or two to separate it. I didn’t have issues separating them cold even with middle bushing dislocated. I didn’t install a middle bushing either and have had no issues. My forks started leaking at 52k miles. Remember to reinstall the seal retaining snap ring.
 
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