1977 KX650-B1. Question about fork rebuild. Can I do it myself?

Hello everyone. I have the forks off of my 77 KZ650. I was going to have my shop refresh/rebuild the forks with either Progressive/RaceTec springs, seals, and oil. I'll probably go RaceTec as I have them in my Voyager 1700 and it has made it feel like a different bike. My question is, I'm getting a quote for 319, parts and labor. Is this something I can do myself at the house? I'm fairly mechanically inclined, but not sure I have all the tools necessary. I'm wondering if the 100-200 I might save might not be worth the time and frustration. If you have an opinion on springs/oil weight, please send them. I'm 220 lbs. Thank you!

I'd never done the forks before but thought it was easy. The problem areas are stuck fork caps. stuck bottom allen bolts & lack of tool to hold inner cylinder while removing the allen bolts. pulling the seals (for some people). The end of the factory inner cylinder tool is shaped like a pyramid & you have to hold it firmly in place while removing the allen bolts. Some guys use an impact gun to get them out.

I do have one cap that appears stuck. I might let it soak a bit then put it back in the triple tree to secure and hit it with my electric impact. I think I'm going to give it a go. If I eff it up, off the my shop guy it goes. Lol!! I've also heard of people using a broom handle cut at 45 degrees to shove down the tube to hold the mechanism. I'm going to try and loosen them before I disassemble. Maybe the pressure of the spring will help me get it loosened up without turning. Thanks Martin!

My motorcycle is a 1981 KZ650-CSR & the forks are basically the same as yours, but not exactly the same. Mine are air forks, so I have to relieve the air pressure first. I originally used a rake handle carved into the shape of a cone. I applied heat beforehand using a propane torch. and also applied heat to the fork caps. For the seals I got an off-the-shelf seal puller from the auto parts store. some guys just use a large screwdriver. I pulled them at the end of a work table & use milk jug plastic to protect the fork tubes. To drive the seals you can use 1-1/2 pvc pipe & fittings.

Thanks Martin! Very helpful!!

When doing the forks in situ, be sure to protect the fuel tank from damage in case a tool or something goes flying.
I just happen have a spare triple tree to act as a clamping device so that the job can be done off the motorcycle. but I still cover the tank. hee.

After draining the fork oil, before disassembling the forks, I pour in some solvent, reinstall the caps, invert a few times & pour it out. It's a messy job. have plenty of newspapers & rags at hand. plus a suitable container or two. The job is kind of a pain the first time or the first fork. but should be easy after that when you know what to do.

What solvent do you recommend? I do have a good quantity of mineral spirits.

Mineral spirits should be fine. It'll only be in there a minute or so. I used lacquer thinner because that's what I had.

If you have an impact gun your easiest route is to loosen the bottom hex bolt using the gun before removing the cap. The pressure from the spring is often enough to hold the damper enough that the impact gun will work. IF, you can remove the hex bolt you can just slide the fork lower off the stanchion without having to remove the cap.
Do whatever you need to re seals, springs etc and just reassemble in reverse. With the fork inverted you can add the required amount of oil through the hex bolt hole then impact tight again.
Saves having to muller the soft ally top cap.

Such great information here! Thank you!!

I've taken apart forks 5-6 times now & never had a problem with damaging the fork caps. mine are different from yours, though. Personally, I wouldn't want to add the fork oil thru the allen bolt holes. At the top fork tubes is easier & is the normal thing to do. to each his own. hee.