Removing the rear shock ?

[Bob Kelly]

Sense there is no info on how to go about removing the rear shock from my 2021 RX4 I have been removing a bunch of stuff just to get down to it....
I may even have to pull off the exhaust header pipe as it covers one of the bolts from coming out....
is there an easy way to get the shock out ? it looks to me like I have to pull the 2 links on the bottom with the shock as it doesn't look like the shock will fit through the modified horseshoe link to come out so I think it's easiest to just drop them all out as one ....
but I am wondering if the 17" long shock will come out of that hole without having to be lifted up a foot !....
right now both wheels are on the floor.... I have a ATV/Motorcycle jack I can lift it with but it is very unstable on that jack and I don't like the bike on it for long !
LOL....
any suggestions ???
Bob..........

[wheelbender6]

I think Bob Kelly has, if you want to pm him.

[Bob Kelly]

Um No he hasn't....cuz that's ME ....silly person ! HAHAHAHA
now who were you thinking about before my name snuck in there ?
....
Bob......

[Bob Kelly]

My spring just arrived, so I'll try to remove the shock on the ground !
( can't no more than have to put the bolts back in !)
....
Bob.....

[Lukas]

I do not know if it will help you but I assume it may be the same as in Rx3, that is you put the motorcycle on the center stand so that the rear wheel does not touch the ground, unscrew the swing arm suspension from the swingarm with wheel but not from the frame of the motorcycle so that it falls down at this point you have on top of the lower shock absorber bolt screwed to the triangle unscrew it the shock absorber is loose at the bottom at this point, to unscrew the upper bolt you remove both seats unscrew the tank bolt unscrew the two side plastics in the left one there is a key to open the rear seat in Rx3 additionally you have to unscrew the side plastics screwed to the tank at this point you can lift the tank and get to the upper shock absorber bolt I hope this helps.

[pyoungbl]

Having removed the RX4 a few times, I can understand your problem. You need to take all pressure off the shock before you can remove it. That means you have to be able to lift the rear wheel almost off the ground. By almost, I mean barely touching. Then you remove the dogbone...all three bolts. It's a good idea to take a photo of how the dogbone is installed just to make reassembly easier. Now you have the lower end free. The top bolt is a bit of a challenge. You need a large allen wrench for the left side. I use the short end of the allen and let the long end rest on the frame. You will have to move some hoses aside but it works. On the right side you have to take off some plastic to expose the nut, then use a deep well socket to get the nut off. Once again, it's a tight fit. I have had to use a magnet to reinstall that nut. Now the shock will drop out with no problem. The second time you do this job it should only take about 20 minutes top. For safety I suspend the ass end of the bike from a rafter so it cannot fall over. It would be easier if the RX4 had a center stand but, alas, that's not the case. Also, a rear stand won't work because that will not take the pressure off the shock. Of course you will use this opportunity to grease all the moving parts. There is no need to mess with the exhaust.

[Bob Kelly]

Originally Posted by pyoungbl

Having removed the RX4 a few times, I can understand your problem. You need to take all pressure off the shock before you can remove it. That means you have to be able to lift the rear wheel almost off the ground. By almost, I mean barely touching. Then you remove the dogbone...all three bolts. It's a good idea to take a photo of how the dogbone is installed just to make reassembly easier. Now you have the lower end free. The top bolt is a bit of a challenge. You need a large allen wrench for the left side. I use the short end of the allen and let the long end rest on the frame. You will have to move some hoses aside but it works. On the right side you have to take off some plastic to expose the nut, then use a deep well socket to get the nut off. Once again, it's a tight fit. I have had to use a magnet to reinstall that nut. Now the shock will drop out with no problem. The second time you do this job it should only take about 20 minutes top. For safety I suspend the ass end of the bike from a rafter so it cannot fall over. It would be easier if the RX4 had a center stand but, alas, that's not the case. Also, a rear stand won't work because that will not take the pressure off the shock. Of course you will use this opportunity to grease all the moving parts. There is no need to mess with the exhaust.

um yes there is a need to mess with the exhaust because you can't get the bolt out of the dog bone ( modified horseshoe link) .... but then again you don't have to take it out it will pivot down far enough to get the shock out
I used a screw jack under the frame with a block of wood and lifted the rear just enough to take the tension off the 3 bolts on the bottom and took them all out.... turns out there was no need to take out the front bolt so I could have left the exhaust pipe and muffler on there !
I took out the shock and yes the top shock bolt gave me fits but I finally managed to get a 10mm allen wrench on the head of the bolt and then used a 17mm on the nut and got the nut off.... then I tapped the bolt out gently
and the shock practically fell out....
got it out and discovered they sent me a 2.5" I.D. spring not a 2"
and they sent me 2 springs not just one like I ordered so I wrote then an email and I'll be sending them back.
.......
BUT I DISCOVERED SOMETHING ! that's an AIR SHOCK ! and it has 150lbs of air pressure in it.... i let it almost all out down to 30~60 psi is all and then re installed the shock and after installing it with the original spring I put some weight on it and it actually flexed this time... normally i couldn't budge the thing with all my weight this time it flexed about an inch or so !
.... so it may well be the problem is solved ! !!!!
so if your bike rides hard ....let some air out of the rear air shock they put 150lbs in it at the factory ! ( no wonder it rides hard eh !?!?!?)
getting to that cap will be an ordeal but you can see it under the tank ...barely, I let out the air on the bench where I could actually get to it ! LOL
I hope that helps someone in the quest for a smoother ride !
.....
Now I have to re assemble the bike I took off the muffler, saddle bags,side plastics, seat and top box..... but I think maybe I got real lucky and found the reason it was so hard riding ! .... too much air in the rear shock !
.....
we shall see !
....
Bob.......
and like a dummy I didn't lube anything and yes everything is kind'a dry.... I should stop take it apart and grease everything.... aurgh !

Bob.....

[pyoungbl]

The 150psi nitrogen is there to provide a progressive resistance and to prevent bubbles from forming in the shock oil. That's pretty common on modern shocks, even the inexpensive ones. It will be interesting to see if bleeding off some of the gas leads to the shock bottoming out. I doubt you will have a problem with foaming unless you are a really aggressive rider.

Kevin Cameron has a good article about shock construction and design:
https://www.cycleworld.com/inside-mo...-how-it-works/

[Lukas]

I, changing the rear shock I had to unscrew the bottom and drain the oil this forced me to find out how it works, because in the new shock I did not know how much oil should be it turned out that the shock without a spring and yellow rubber bumper should come to the end and slightly return and so I did in a new shock absorber unknown Chinese brand, because I used the old spring for a new shock absorber I only had the body of the old one, I decided to check how it works, it turned out that it is tragic, there is a lot of air in it and it does not bounce at all I am going to dismantle it for curiosity's sake I recommend changing the oil in it I used KYB K2C.

[Bob Kelly]

I figured it might be nitrogen in the shock but on a HARD riding shock that is a very quick and easy solution just let some of the pressure out !
I didn't let it all out just most of it and I can now feel some give in the rear when I bounce on it.... not much ...but some !

... I won't have any problem as I am not an aggressive rider anymore !
....
I left the saddle bags off the bike because I want to try it without them for a few rides
I know on my other bikes in the past it made a big difference in how the bike handled
so I wanted to see what this thing is like with them off !
....
I'm going to try and take it for a ride tomorrow , as it's a bit late for that now, and
it's getting cold outside....
with that in mind I bet it rains all day ! LOL
....
Bob.......

[Bob Kelly]

Well I did take it for a ride and although the bike was noticeably more agile it still rode like a truck... so I ordered a spring from Race Tech.... i had to call them because of their site doesn't have the CSC RX4 and everything on their site goes off that to look in their inventory... I gave Matt the dimensions and he found 3 that matched and I got the hardest one he had the 537lb one ( i just hope it's not too stiff !)
Matt was alot of help it's worth it to call them because their site is so screwed up you can't find anything !
anyway the spring will arrive tomorrow and I'll put it on and we'll see if that does the trick or not... it cost around $160 after the shipping was added !
it should swap out with no problems at all !
I put the saddle bags back on and had to fight the one bracket because it was sprung and the bolt holes didn't line up but a long lever and a bungee cord took care of that. UPS sent me a note and said it will be here tomorrow so I may go pull the shock tonight i dunno.... it's trying to rain here today ! AGAIN !
.....
Bob.....

[Bob Kelly]

Well I got it on there (My spring came today)...took about 2 hrs, but I took my time.
it feels pretty much the same though.... maybe a little softer but not by much....
I haven't rode it yet but I hope to soon and see what it does for the ride....
I did lube the suspension link/knuckle and I am real glad I did, only one bearing had grease in it !!!!!(THE ONE THAT ATTACHES TO THE SWING ARM) and as far as the bushings go that are outside the bearings they were completely DRY nothing had been put on them at the factory.... so if you have a RX4 you might better check the lower link and it's pivots, they were all dry as a bone on my bike ! !!!!
.....strangely enough you have to pull the seals off to get the bushings out....strange but I guess it works.....
I Knoticed that EVERY pivot point was extreamily hard to turn or make flex in the bracket..... you almost have to take a hammer to it to make it rotate and that's not RIGHT.... might be 90% of the rough ride right there ! if it can't flex it Won't ! and that is what I have been feeling... i did lube it up so we'll see if that helps ,I doubt it will though as they are very hard to turn in their holder
....I suppose I might have put it together too tight before.... this time I snugged them up and put blue locktight on the threads.... last time I put the impact driver on them !
LOL.....
nothing is bent or crushed.... just hard to turn like a rubber bushing in a hole with a bolt through it ...it just don't want to turn at all.... and that is the suspension for the rear...add up all those joints that don't want to turn and you'll have a huge amount of force you have to over come to get it to flex.... sounds like I found the "Rough ride" to me !......
I may have to drill and pin each bolt and nut on those pivots but if I do that it will pivot on the bolt alone because it is the loosest.... I may have to pull it off again and do surgery on that link/knuckle ! I know that the pivots should turn by their own weight
only one does and that because I took it all apart and lubed the heck out of it and worked it for 10 minutes (that was the pivot that goes through the modified horseshoe/dog bone...) i did get it freed up nicely the other 2 well, I lubed them but didn't waste my time turning them for 10 minutes !
....everything fit together like it should and no extra parts ! so I must'a did it right !
LOL !
Bob.....

[Bob Kelly]

Hummm... I just had my Kid come out and bounce on the seat She's lighter than me by 50~75 pounds but there should be some flex in the swingarm when she bounces on the seat....Right ? the tire flexes but that is all and I looked real close there is no movement in the swing arm at all..... WTF !?!?!?!
so either the spring is the same weight as the original one or something else is going on here ....


I think I will air up the tires both of them and put them at the recommended pressure and see how it rides that way....
( I already know it will be like there is no suspension in the rear ! )
I think I will loosen all the bolts on the suspension down below too before I take it out of the shop.... I won't ride it far but far enough to see if the rear gives any at all....
I think I will be buying a 450lb spring next.... this one is a 537lb spring the invoice says 500 pound but that may well be the catagory it was pulled from by the guys in the warehouse.... it's supposed to be 537lb.
....
it's silly that rear swing arm didn't even flex once with 145lbs bouncing on it
i don't think it did when My 185lbs bounced on it either.....
.... so I am left wondering what the stock spring rate is !!!!! and what the heck should it be for a soft ride.....
....
this is becoming a pain in the ass ! .... no pun intended ! LOL
No bike should ride like this one does so something Must be wrong with it.....
there is not much to the rear suspension 4 pivots and a shock and spring
.... I'm about ready to take the whole rear swing arm off the thing and see what I find
if the swing arm pivots are as dry as the link/Knuckle was it needs lubed anyway...
....it's like the rear suspension is froze up.... but it's a new bike !!!!
I dunno I gott'a think on this for a while !
Bob......

[Lukas]

Dear friend I recommend to unscrew the swing arm and lubricate the bearings, because there is no grease in them, the same way lubricate the entire suspension I unfortunately became interested in this after 5 thousand and it was too late I replaced everything, but by the way I unscrewed the wheels and lubricated the bearings in them, if you want to do it right use this grease it has an amazing viscosity, and can you tell me what problem you have with the rear shock that you change the spring I was left after experiments something like this. grease was recommended on motocross.Motorcycle must have SAG set properly after shock service.

[Lukas]

35mm Static Sag. "Bika under it's own weight".
33% - 1/3 of suspension travel, Rider Sag... "Rider on bicycles" is supposed to be like that in the RX3, but with the original shock travel this setting does not work properly until with a longer travel shock it is possible to achieve a similar result, at least in my case.