89 KDX shock oil change and re-charge?

jlapolla said:

The local shop tells me that the shock I have that is way too soft is most likely needing a seal replaced if the shaft is not worn out? The cost is $136 to just tell me if this is the case.

Can the nitrogen just be re-charged on the bike?

Or, how hard is it to remove and get it cheaply charged and re-oiled?

Thank you for any help!

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$136.00 plus parts for a rebuild sounds expensive.

Check out Jeff's pricing:
http://www.frpoffroad.com/kdxposed/services.aspx

Or MXTech:
http://www.mx-tech.com/services.asp

Is it leaking oil? The seal head and shaft are probably alright if it is not leaking oil.

A re-charge of nitrogen probably won't fix the problem but I am not sure what you mean when you say the shock is too soft.

With a shock that old, I would suspect a worn out piston ring and/or shock body. Especially if it did not receive regular maintenance.

If it leaked the oil, there should be a mess of greasy caked on dirt all over the lower shaft/bottom out bumper area.

I just had a 1986 XR250 shock refurbished because it was leaking. The seal head was bad and the shaft needed to be re-chromed. It ended up costing me $200.00. If yours has similar problems you may be better off finding/buying a used shock from that “e-by-the-bay” site. You can probably find a good usable KDX shock for under fifty bucks. Go for a shock that has been serviced regularly and recently. If you find a good one, you can just bolt it on and go riding.

I'd suggest calling Fredette. He likely has several used ones and could check them out, rebuild, revalve, etc before he sends it to you. I don't know if he still has it or not but I sold him my KDX extras after I built the hybrid bike. I bought the DX new and it only had about 1000 miles on it. Jeff had gone thru the shock and revalved it shortly before I built the new bike. I'd trust something coming from him much more than from the auction site.

Servicing the shock you could do yourself and save yourself the most money.
There are some things (if bad or worn) will require you to have it done by someone else.
The first thing I would do is to see what the shaft looks like under the bumper. This does not require you to remove the shock. Just degrease and wash the shock area, and blow off till dry. Then push up the bumper with a long screwdriver, and look close to see if the lower part of the shaft is rusted.
If it is rusted it will need to be re-chromed. At this point even without seeing the inside of the shock
I would say that you'll end up throwing a good bit of money at this shock and might be better off to find one that has already been gone thru.
Ok, so now you do this and see that there is no rust proceed to step 2.
Pull the shock off and start to do the oil service. Once you have the shock apart check for worn parts: shock body,piston, seal head, bladder... If the shock body is in good shape then move on to next step.
This step is your call, but I would put in a new seal head and piston and change the bumper if it is cracked.
Put your choice of oil and recharged and your done.

That being said, and over compressed spring that has been ridden hard for a long time will have lost it's rate and need to be replaced.
So if you can't do or perform most of this work and observations then I would just buy another shock.
Good luck, and have fun.

Quick edit to the springy thingy. The lost of rate might not fall into the rate that you need to support your weight. So check the spring for the right sag adjustments.
Hey, I gotta go ride! :aj: Latter

regular maintenance???