rebuilding showa shocks

In doing my research on rebuilding the stock shocks, I have found that the rear for my 04 R1150 rt can be rebuilt, the front not so much. Curious as to how many others have done this themselves versus sending it out to be rebuilt by someone else? Have tracked done two groups that will do the process for us- Lindeman out of California (only does this on Tues now days due to change in personnel) and EPM- not very happy with their customer service- when I mentioned to Klaus that I wanted to rebuild the shock on my own but wanted to order the parts through him for it he straight said "figure it out yourself" and hung up. I get it, in essence it is taking away business from him but I was still going to buy the parts through him which is half the process, such is life.

In the end, went with buying a new Hyperco rear spring and shock seal head assembly through Race tech. Very helpful customer service as they even helped trim my order as I had a few duplicate items I didn't need on the initial order. Total cost (will still have to recharge the nitrogen) is about 205 with tax and shipping and some of my personal time to do the labor on the weekend. Not a bad dent considering that the cheapest premade shock I have found between YSS, Hagon, Hyperpro, Wilburs, Penske, and Ohlins is between 500-600 for the rear less I go used through ebay and then it only drops down to 400 and I would probably have to send it out for rebuild after that.

I know there is a huge contingent out there that will say why take the time to rebuild the stock shock? Honestly, unless there is a structural issue with the shock body itself, by replacing the spring and the assembly inside, it isn't very reflective of the stock showa shock after that in the end. Anyone know of any issues past brand name recognition why this shouldn't be done?

I know of no issues why this shouldn't be done.

I have a 2000 R1150GS. I opened up the rear shock to revalve it. [i am obsessed with getting into everything.] It is straight forward shock construction. How did you deal with the nitrogen recharge? I released the nitrogen by drilling a hole in the body, drilled out the peens holding the piston stop in place, removed the piston, brazed a nut for a shrader valve on the body, and charged that way. [later I added a hose-connected reservoir at the 'schrader nut' site.] I think the nitrogen charged portion of the shock would not need to be disturbed. It has been so long ago that I worked on it that I don't remember what process I followed. I think I assumed the oil portion was under pressure, so I released the nitrogen first. Now I wonder if the oil portion was under pressure. I think just remove the seal head, replace parts as needed, reassemble bleeding out as much air as possible. How did you do it?

I am eye balling the front shock, which, as you know, the open end of the shock body is swedged over the seal head. I am thinking I can cut the swedged portion off to get the seal head out. Do you know if there is a circlip to retain the seal head? If there wasn't, I figured I could cut a groove for a circlip. [i have a lathe.]

For those who are interested, I recharged my shock with air. Suzuki says DRY air is ok. All gases react the much the same way as far as pressure change with change of temperature. I think the concern with air is the moisture in the air. Moisture and oxygen are reactive. Reactive means deteriorative effects; rust, degrading of rubber [bladders], deterioration of oil, etc. I am able to pressurize to 150psi plus using a bicycle shock pump. Since I open up the shock [too] frequently for revalving 'experiments', I don't worry about deterioration.

Why did you change the spring?

I don't suppose either of you have photos to share of the disassembly? I'd love to see how doable it is for an average DIY'er.

Thank you for the replies, I was beginning to think I was alone in this aspect of the universe. As for my rebuild, I would have started it last weekend but upon getting my bike back together from the winter tear down (replaced the Piston rings, chain rail guides and a few other items) I then found I had a rear main oil seal leak so I am currently dealing with that prior to working on the shock.

The nice thing is I actually have a second rear shock which I intend to do the rebuild on and then place on the bike to see how I did. The stock spring that came with it is good but from what I have read it isn't really meant to last for too long with a guy at my weight (250#) plus gear lol. Went through a company called race tech and purchased the shock seal head assembly and a new hyperco spring through them. The spring is meant for my weight so should result in a much smoother ride for the bike- similar in aspect change to what wilburs/ ohlins and all the other aftermarket shock claim as well in tailoring the shock to the weight and ride type of the rider.

When I finally get to the shock (goal is this coming week as the bike is almost done, again) I will try to remember to take some pictures and post them on here. Shouldn't be too difficult I would think, I have changed out many a shock/ macpherson strut on my cars and trucks.

I will post the step by step process [with pics] for rebuilding the shock next time I am into it for a revalving. Be aware that getting the spring off is the biggest challenge. I have a press I use to compress the spring so the retaining clip can be removed. As the spring is about an 800lb/in item that has to be compressed about an inch [!], it needs to be held securely so it doesn't launch. I made up a plate from 1/4" steel to catch a narrow edge on the retaining clip guide. I have seen shock spring tools that could be made from 2 threaded rods and fixtures on both ends, that shouldn't be too challenging to fabricate.

It will be a while before I have time to work on it.

I had both the front and rear shocks on my R1150RT rebuilt and re-sprung by Linderman. I have a sidecar so 1100 lb spring on the back and 400 lb on the front (if I recall correctly). The front shock can be rebuilt if you find one that has the machined cap on top instead of the swagged or welded ones. Looking on ebay it seemed that more of the ones from the RTP had the machined cap. Linderman does something similar with adding a shrader valve so the rebuild cost is higher the first time then subsequent rebuilds.

Thank you for the replies.

From everything I can tell, everyone prefers the after market due to resale value and from hearing other people say that they are so much better. Problem is that the stock shock in production form is meant for a driver that weighs in around 170, give or take. That being said, a guy like me who then comes in between 235-250 (depending on the year we are looking at) will then weigh down the spring much more quickly versus an aftermarket which has a shock built with a spring geared towards the higher weight.

I fully believe that the stock shock rebuilt with this heavier spring should be able to present a similar performance to the after markets once the rebuild is complete. The other side of the coin is that not many people want to spend the time to gain the knowledge or have the tools to complete this, therefore it is easier to buy the after markets. Will update how this goes for me once I have it complete, dealing with some other issues on the bike at the moment.

I can not find how to attach more than one 90kb photo at a time. I have seen other posts with more than one photo, but it looks like there is a limit. Can anyone explain it to me?

I recently took my shock off for revalving experiments. This bike is a 2000 R1150GS. One hurdle is removing the spring. I use a press to compress the spring about one inch to remove a clip from the top end of the shock. There are tools available for compressing the spring.

The cap at the end of the cylinder is pressed in. The technique to remove it is to use a chisel to get a purchase on the cap to drive it out of the body, working from side to side.

Under the cap is the seal head, which is held in place by a wire clip. The seal head must be displaced into the cylinder about 1/4 inch to expose the clip, which can be dug out with a small sharp screw driver. Then the shock rod, seal head, and piston can be removed from the cylinder. The big question 'Is the oil in the cylinder under pressure?' I don't know.

The other end of the cylinder is under pressure from nitrogen gas. There is a floating piston separating the gas and oil. There is a metal ring midway in the shock acting as a stop for the piston. The ring is held in place by 4 peen punch marks.

When I dismantled my shock the first time [years ago] I released the gas by drilling a hole, then drilled out the peened areas, removed the piston and ring, brazed the holes closed. [The shock oil piston does not travel as far as the peen area.] I added a remote reservoir to the shock by drilling a hole in the cylinder near the end, brazing a nut over the hole for the reservoir hose fitting. The remote reservoir has a compression adjuster. To retain the stock floating piston setup and release the pressure, drill a hole near the end of the shock, then braze a nut over the hole for a schrader valve. Position the schrader valve so it doesn't strike the wall of the shock tunnel on the motorcycle frame.

So I don't know if the oil side of the shock was pressurized. Probably it was. It still might be possible to remove the seal head by pressing it down with a tool to access the wire clip. When reassembling, bleeding all the air out might be possible, however, a little air would not be a problem. When bleeding the air out, there is a small hole in the side of the cylinder. Position this hole up.

AND THEN, the goal is to replace the seal head, piston ring[?], and oil. To remove the seal head from the shaft, the nut at the piston end of the shaft OR the clevis at the other end has to come off. As my intention was to change the valving, I removed the nut. The piston end of the shaft is peened over to retain a valve in the shaft for the rebound adjustment and the nut. The peening needs to be ground off. I have never removed the clevis from a shaft. It shouldn't be too hard. A collet would be needed to clamp the shaft in a vise. Race Tech has those collets. Or make one.

I am not sure if a piston ring is available. Probably is from Race Tech. The stock ring is one piece. I found there was considerable drag from the piston ring in the cylinder. The drag is source of 'stiction'. Since my goal in revalving was a smoother ride, I turned off about .006" in a lathe until the drag was barely enough to stop the shaft assembly from moving when the cylinder was verticle. If a new ring is being fitted, the old ring can be cut off. Rach Tech piston rings are split at the end. If I were rebuilding, if the piston ring was still dragging on the cylinder more than a little, I would just leave it.

It is possible to buy just the seals and rod guide bushing separately, but a seal head already incorporating those parts is the was to go.

If the chrome is worn off the shaft, or the shaft is pitted or scratched. Get a new shaft. Maybe Race Tech.

This whole process in covered in some Youtube vids, although I didn't find any covering this shock type.

SO.........that's how it's done. I pressurize my reservoir with a bicycle shock pump with air to 150psi.