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shock rebuild

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Okay TT,I have a few questions! the shock is from an 03 yz250f. before i posy pics and ask questions,let me start off by saying that with the oil in the shock and the nitrogen in there, i removed the clevis.why? i have no idea. i took on the shock with no instruction, I didnt know what i was doing and i wasnt expecting what happened(removing clevis result). which was all the oil shooting out very fast and the rod came out very fast as well,luckily, no one got hurt :smirk: just a big oil mess was left and me here with a few questions.

since the oil shot out,I have no idea what the oil level was at before and i have no idea how much(OZ/mL) oil was in there. I also have no idea which way the rod goes into the shaft. so here we go.....

1.) does the rod go in like this(pointy end out)...


or like this(pointy end in)...


2.) Do i install this like the picture shows? or should i squeeze it leaving indents in the rubber so more nitrogen can be filled in there?


3.) I didnt know to remove peening,so i took off the shaft nut with the peening on there completly,not grinded down at all. all peening is now gone.


I want to use red Loctite on the nut but i dont know how hard i should tighten the nut? should i tighten it down as much as i can? I honestly dont ever plan to remove the nut again so if its on there really tight,fine with me! this nut can not come loose while im riding!! tightening the nut down as much as i can would make me feel safe along with the loctite. The shock didnt need a rebuild/cleaning, I just did it for a peace of mind. Also, Ive tightened the shock shaft nut down as much as i can but with no loctite,when i do that, the shock piston does not move up or down freely at all and it does not spin, do you want that? or does there have to be play?

5.) can someone tell me how many OZ or mL of oil i need in the shock? or give me an idea at what level the oil should be at?

I plan to get the shock to stock setting, i will adjust the shock by rebound/dampning and i will set my sag. for me, thats enough. Im not putting oil and nitrogen in the shock according to my weight.

also, it would be easiest if you answered lke so...

1.) your answer

2.) your answer

3.) youe anwer

and so on.

thanks TT!:smirk:

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Ok... not 100% sure about the dampner rod but I believe it goes towards the rebound adjuster... oil level is fill it up all the way. Put the shock on its side with the bladder in but no psi do not sqeeze it. fill the shock up. bleed the shock slowly fill as needed till no air bubbles. you can now screw the cap on and fill the bladder with two psi from a bike pump to help push the air up... let the air up slowly perge again and fill accoringly... put the cap on without the adjuster fill slowly as you screw the adjuster in better purge but difficult... watch the seal! very easily damaged. and yes replace the nut above the pinston first chase the threads lapping compound works well use the old nut to chase it. And well cured loctite "with time" is a must! and yes tight. google spi shock rebiuld...

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the pointy end of the rod goes towards the nut , shocks have to be bleed well , take the nut off , red locktite and tighten to 25 lbft , don't squeeze the bladder

find sone videos on bleeding the shock

you were lucky you wearnt hurt from that rod shooting out , take time to research next time

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Read and understand this entire document before proceeding farther:


To your questions:

  1. The rod is the metering valve for the rebound adjuster. It goes in with the pointed end up by the piston and valve assembly, not down by the clevis. When you install the clevis, be sure the rebound adjuster is backed off all the way out.
  2. The bladder is installed as you have it shown. It's easiest to slide in place with no pressure in it. If it collapses, don't worry about that until you get it in place, at which point you can put 3-6 psi of air in it to restore its proper shape. You also need to know which direction the valve faces so it will be accessible and clear the exhaust. If you didn't mark that, you may need to put the upper body in place on the bike and figure out the orientation.
  3. The nut should really be replaced. SMART Performance has 12mm lock nuts on hand, and can send one right out to you. If your judgement is that the nut is still sound, you definitely need red Loc-Tite. Be sure you clean the threads free of oil and give the Loc-Tite 24 hours to cure before assembling the shock. As you have it pictured, the gap between the piston and the rebound shim stack is incorrect. The nut should clamp both shim stacks to the piston, and the piston CANNOT float up and down on the rod. Tighten the nut to 25 ft/lb or 300 in/lb.
  4. The shock takes a bit less than a quart to fill, but there is no oil level, per se. The unit is filled completely full and bleed as free of air as possible. See the document for more on that process.

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