identifying RM shocks

[LWC82PE]

The top shock (RM 78 C) I have already got partly apart. Since there was no valve I couldn’t release any pressure first so I just slowly un did the hose and removed it with no drama. By the looks of it there is still pressure in the reservoir as I can see its pushed the piston to the end of the reservoir. I removed the cap (not shown in photo), seals and bearing an got down to the second c-clip but now there is a steel plate I cant remove. I think it’s attached to something underneath and there must be a ridge inside the body where the line or indentation is on the outside and that is stoping anymore parts coming up any further. They must put this impact mark in at the end of assembly so to go any further on that shock or on the PE shocks I think I have to cut them open and that’s what I want to be sure of. I would think they have to be cut on or above the line ( towards the top eyelet end) I’m thinking that maybe I can carefully cut on the line but have to be careful not to cut anything inside. On the 78 shock I can just compress the shaft to get the piston out the way but don’t know what to do with the PE one as its all still gassed up. I’m thinking of just leaving the 78 RM shock as I only really want to get it apart to look inside and to use it as a trial run before doing the PE ones.

I cut the 1980 RM shock open today in the middle of the weld and removed the top cap part but now what? There is still a steel seal holder or bearing in there. Its all in there very tight and I cant see how to get it out yet and cant see a join or where the shock body wall begins. When I cut through I did actually go a little too far into this other steel bit. Maybe I haven’t cut quite down far enough? Do I need to cut another ring off a few mm wide?  Whats the next step?
I would be interested if you had a RM-T shock Brent but nothing if you thought it was too stuffed for you to use yourself. I would consider swapping it for the 78 RM shock as its really no use to me and doesn’t make a pair with the RM-T shock. Before I pulled it apart it still had lots of good damping and felt good inside and didn’t appear to be leaking. It has 3 way adjustable damping on it.

[YSS]

I cant remember how many of those shocks we used to repair until we started making our own shocks.
With $75 per hour labour its much easier to make a new shock  They only cost $450 , so why bother?

[Doc]

not everyone can afford $450 for shocks Walter. I know I can't You have a wonderful product and don't take this wrong as I'd have a pair of your shocks fitted in a flash given the opportunity, but for me having my stock LTG shocks rebuilt for around $200 locally is a little more practicle. I still can't afford it regardless but this option is tempting after seeing the quality of their rebuilds. It's really becoming less and less of an issue for me as I rarely ride anything with over 4 and a half inches of travel these days..regressing you might say  

[YSS]

Thats fair enough Doc , but I can not see how you can cut the bodies , rechrome the shafts , new sealblocks , capping , new eye bushes and at least 3hours  of labour  for $200 a pair . ( Perhaps per shock maybe).
If somebody can do that , I will send my work to them .

[oldfart]

Walter they can and are doing it for that price , with good results .
I have priced up new shocks for my old dungers , which are almost twice the price you have posted 

[YSS]

Rad is a customer of ours and I did quize them on the $200 deal , with all the things listed done , no way.
When you enquired , what model did you get a price on?  There is the E302 , Z 302R  and G302RC  , Z366R
G366 RC  , G 366RW  and very soon the E 362 , Z 362 And G 362. 
They are all possible options to use and they all have a different price and features. 
But like I said , if you can do the originals for $ 200 , why not .

[brent j]

Leith, try a second cut a few mm down the shock body. The lower edge of the weld is probably still holding. Once it's through the seal head and rod will pull out.

I looked at a set of rebuilt RM250A or B shocks about 6-7 years ago. They were done in QLD but I don't know where. They were welded but it struck me that it seemed a shame to go to all that trouble just to seal them up again, I was in the process of making mine rebuildable and adjustable.
If they weren't particularly good shocks to start with they won't be any better if they are just overhauled ie no change in damping. I also wondered the affect of the heat on the seals when welding the bodies when they were assembled but they seemed ok.

I would not rebuild a set of shocks the way I want for the prices I've seen. I will continue to do shocks for my XT race bikes because cost is not an issue and I have access to several good workshops. Being a machinist helps too. I do my own to learn more about suspension and I do enjoy playing with things I probably should have left alone in the first place.
I'd love to have 2-3 sets of nearly identical shocks so I could compare small changes such as damping and such. Yeah adjustable shocks would be easier but this is my fun!

For my other bikes, two standard XT's and two TM125's I'll be buying shocks as none of these bikes have any.
What will I use? I'm not kissing anyones arse here but Walter has been very forthcoming with help and advice where other suspension people have just said "Send it to me" or "just buy my product".
A local, rebuildable, adjustable product with local support. Not a hard decision

Having said that if you want any help with your shocks Lieth let me know. I may be able to save you some trouble. 

Brent

PS Leith, still can't find that shock but looking

[LWC82PE]

You have to look at it from a restorers point of view, not a racers or aftermarket manufacturers point of view. As far as I’m aware the original Suzuki KYB shocks are NLA so us RM/PE restorers are left with no other option but to fix the original shocks. To us it is about restoring the bike to look as original as possible as they left Japan. We don’t have the luxury of having ohlins or marzocchis fitted as standard equipment like KTM and Husqvarna for example. And if you’re building a bike to race or ride hard and are not intending to return the bike to factory specs, then yes you could and would want to fit some aftermarket brand shocks. Cost is not always the deciding factor.

Anyway if I have understood oldfarts directions the place to cut is 35mm from the end which is a few mm above (as the shock is positioned on bike) the indent on the body and then another cut 12mm above that? See my photo.

thanks Brent i will see what i can get up to on the weekend

[LWC82PE]

oh Brent i will also keep you in mind for any help i may need thanks!

[oldfart]

NO NO... DO NOT CUT AT YOUR  12mm mark
35 mm measurment is correct
12 mm measurement is measured at the  RHS side ( flat section piston ) to the left , or come back  23 mm from the 35 mark . 

                                                                  I......35..........I
                                                                              I..12..I
                                                                  I....23....I       I
                                                                                               able to understand this
                                                               

[TM BILL]

Walter do you think there could be a market for replica RM shocks ?
Something that is visibly the same as the late twinshock RM shocks with your modern internals , adjustments  and rebuildable.
Just a thought as a lot of people want to retain the appearence of their Suzuki .

[YSS]

Yes that is not a problem for us , but ... how many ? Lets say we made a run of 100 set , that would cost around 1000 per pair , lets say we make 1000 set , that would cost about 350 a set. And so on , the more we can make in a run the cheaper they get. Its not the shocks that are expensive , its the set up costs and moulding cost. next problem , who will buy and stock 100 set or 1000 set . If you can imagine our set up in Bangkok , we do not stock shocks . The rawmaterials come through the front door and pallets and containers leave everyday the backdoor (5000 shocks everyday) . You can see even 1000 sets are done before lunch . Everything is made to order. Trying to build 100 sets is like trying to run the Queen Mary through a Slalom course.
In the end its cheaper for the consumer, if we use common modular parts and make a shock .Then you have spares and springs to suit.
If someone wants to cut and cap original ones , we have the shafts ,sealblocks , and modern pistons to do that. I can do that from Australia ex stock.But when you think about it , when you cut and cap an original shock , its not standard and pure anymore . But if someone wants to do that , they can in their time.
Very shortly we will release the new E 362 series ( 12mm shaft with 36mm bore) . With that we will be able to cater more for the budget.EVO class .

[LWC82PE]

Well I got the RM –T shock apart once I cut a little lower. The first cut in the middle of the weld was no good, you have to cut the edge of the weld.

At this stage I think have decided against adapting the adjustable damping mechanism into the PE shocks after now I can see how it’s done. I don’t think there is enough room due to the piston at the top of the body and different strokes between RM and PE and I want to keep the stock PE shaft as I want to keep the stock bottom eye which is cast onto the shaft so I cant simply fit the RM shaft (which has drillings), shorten it to the PE length and fit the PE bottom eyelet. It’s a bit too difficult and too much calculations for me to do the moment with my limited time. If I was willing to not have the original PE bottom eyelet and I could get a seal block made short enough to allow the extra 12 or so mm of the damping adjuster then yes it could be done by using the RM shafts or getting new ones made. So at this stage I will just rebuild the PE ones and fix their major flaw of harsh damping (rebound especially) and fit some decent hi quality oil.

I have discovered that one PE shock looks like it has a bent shaft so I’m now again looking for another PE shock or pair.

It’s now clearer to me where the PE ones have to be cut, but I haven’t done that yet. Before I go any further I need to know how I can get them re-gassed. Remember these are not remote reservoir types, they have the floating piston and gas chamber at the top of the body, not ideal performance wise but it was a compromise that the PE’s had to have due mainly because there was no where to mount a reservoir because of the battery location on the left side of bike. This is also why the Australian model 82-84  PE 175’s did not get a remote reservoir shock on the full floater but most other countries did.

I was given a photo (not a real close up one) of a PE shock cut open at the top and it looks like there is a pointy metal thing sticking out into the body. I was told this is just a metal ‘thing’ and no valve was present but we both think that KYB somehow inserted the gas at the top of the body through this point and then afterwards welded the top shock eye over the top.

Unless someone can tell me otherwise I will have to get these shocks re-charged with gas through the top of the body somehow. If that is the case then I need to drill a hole somewhere. There is a second reason for this. I could just start cutting them open with out letting the gas out and the piston will get pushed down lower and oil will get pushed out. No huge drama but I was thinking that It would be nice to know what height to set the floating piston to at rebuild stage. To do this I would need to depressurize the shock at the top first which I think would set the piston at correct height. Then I can cut open shock, remove internals and then take a measurement at where the floating piston is sitting. I have got books that tell me the floating piston height in the RM shocks but not PE!

Then I can drill only one hole at the top of shock for letting the gas out and it can be at the position at where to put in a valve. There is no point drilling one hole to let the gas out, filling it up and then drilling a hole for a valve in another place. It makes much more sense to plan ahead and work it all out first and only drill one hole in each shock which Is what I want to do.

I would prefer not to have to fit a valve at the top of the shock but if it’s the only way to re-gas then I guess I have to. There is very limited room for a Schrader valve so I guess my only option is a small needle injection valve. I need something short and compact and I’ve got about 2mm thick to tap into. Once I know what valve I can use and how big it is I can work out where to put it and that same hole will be the hole to let the gas out an then I can start cutting them open.

I’m yet to decide how to do the caps. I want to try and keep the original look so I could maybe get caps made to look like the welded on original ones and even run a fake weld around it, or I’m thinking of getting another 78 shock so that I then have 2  of the 78 body caps and use them as at least they are original KYB parts. Once I get these apart I will get someone to make me new seal heads and if I can get all the info required I will rebuild them my self or get someone to do it for me.

I’m still looking for one RM 250/400 T shock or a pair as well.

Thanks for any ideas.

[LWC82PE]

I phoned RAD today but they wouldn’t tell me how to re-gas the shocks other than that they don’t stick a valve in the end but they do drill a hole at the top and then re-gas through that hole and then some how then weld it all up with out gas coming out which is a bit of mystery to me. That’s all I could find out. I was also told that they don’t make the PE ones re-buildable with a re-moveable cap but they weld them back up again and he said to rebuild them you have to cut them open again they have to be cut open and you only get about 2 goes at doing this and then they are throw aways. Welding them up again kind of defeats the purpose to pulling them apart and like Brent said there could maybe be an issue with heat from the welding damaging the seals?.

[YSS]

Leith , you have to understand why RAD are not going to tell you how they gas them up . Thats years of hard work to figure out all the different ways and make tools to do it. I can understand that. Would you put your credit card numbers on the internet?  I can understand that.  Just send them the shocks and pay for the job and then when you get them back , you can see how they did it .
We have rebuilt many of those shocks over the years and your thread is a bit amusing to me. Do you ring a barrister company free of charge ,on how to win your case ? Definitely not. We have people ringing , what we are doing to modern front forks and could we send them a specsheet please. When you say no , they get angry and hang up. Giving some basic free advise on how to set things up , OK , but giving away years of experience , NO. There can be a bit of a fine line sometimes .