Play in upper shock mount

I noticed my swingarm had some play in it on my 2004 450EXC. I decided to check the shock to see if it's bearings need replacing as well. The lower mount had no noticeable play and the upper mount had a little bit both side to side and up and down. I did a quick search and found a thread saying side to side play was normal but I don't know about the up and down movement. Will I need to replace that as well?

 

I saw a tool online (Morgan's Tool) for changing swingarm bearings that looks to basically be a big bolt with some spacers/washers for pushing the bearings in/out. Does that tool need to be very precise to seat the bearings correctly or would it be reasonable to DIY one with some stuff from a hardware store?

I did it myself with stuff from the hardware store. no special tools needed.

I don't have any play side to side or up and down,  check for bolt tightness, otherwise the spherical bearings are probably shot.

 

First thing I did with new bike was inject dielectric grease in those spericals, 300 hours no play as of yet.  Regular grease contains metal, it eats at the Teflon races (they are supposed to be dry, but that really doesn't work for a longevity basis).  Also hosing the bike with a water hose will not help in those areas, if they get contaminated..

 

doing the large lower spherical , I would measure exactly where its at , in the sleeve for installing a new one, looks like you have some margin there,  top one has seating rings.

 

On a side note, Ive heard those top sphericals, wear out within 100 hours , unless dealt with early.

Okay thanks. I'll get a new top bearing.

I did it myself with stuff from the hardware store. no special tools needed.

Sweet. Can you guide me on what exactly I might need?

Socket, extension bar and a hammer. Don't buy bearing connections kits, the spacers don't fit properly. Go with a genuine KTM kit...

Pulled the swingarm and shock off today. The swingarm pivot bolt was stuck in there pretty good. I was eventually able to get it out but I mushroomed the threaded end in the process so I will need a new one. Does anyone know if that same bolt was used on different models? I guess one from a 2001 520EXC or MXC would work on my 2004 450EXC as well?

Pulled the swingarm and shock off today. The swingarm pivot bolt was stuck in there pretty good. I was eventually able to get it out but I mushroomed the threaded end in the process so I will need a new one. Does anyone know if that same bolt was used on different models? I guess one from a 2001 520EXC or MXC would work on my 2004 450EXC as well?

 

Nope, the part number for the swingarm bolt that you need is 77304037000

 

munnracing.com has an excellent Parts Microfiche

Edited by boney95

Got the swingarm pivot bearings out. It was no problem once I started using a bolt and nut to draw them out.

 

However when I went to replace the lower shock mount, I couldn't get the spacers out. No matter how much I hammered at them from the inside they weren't budging. So I tried to press out  the entire bearing including the spacers all at once. I got it to move just a tiny bit, then no more luck. It wouldn't budge at all. The swingarm ended up cracking from all the force before the bearings would come out. It also appears that the inner race of the bearing popped out rather than the outer race sliding out.

 

I'll be looking for a used swingarm now.

crackekdSwingarm.jpg

Got the swingarm pivot bearings out. It was no problem once I started using a bolt and nut to draw them out.

 

However when I went to replace the lower shock mount, I couldn't get the spacers out. No matter how much I hammered at them from the inside they weren't budging. So I tried to press out  the entire bearing including the spacers all at once. I got it to move just a tiny bit, then no more luck. It wouldn't budge at all. The swingarm ended up cracking from all the force before the bearings would come out. It also appears that the inner race of the bearing popped out rather than the outer race sliding out.

 

I'll be looking for a used swingarm now.

Is that the spacer still in the Bearing?

 

My lower spacers pull out really easy, that thing must be totally corroded and froze up.

Yes. The bearing was hardly functional when I first started. After banging at the spacers for a while it got a bit looser so I could partially rotate it. Anyway the spacers wouldn't come out at all. It was all kinds of corroded.

 

When I first decided the spacers weren't going to leave the bearing behind, I started hammering at the whole thing. It budged a couple mm. Then it wouldn't move at all. I took it down to the vice and put a big socket around one side and a little socket on the other side and started squeezing at it. It eventually made a big bang and ended up as you see in the pics.

 

 

Is there anywhere or anyone who could help me find out swingarm interchangability between models? Just looking through ebay, the 200SX has a similar looking one but the part numbers aren't the same and I have no way of measuring its dimensions.

I can't help much with the interchangeability of swingarms between models, but I can offer simple and cheap solution for the lower shock mount.

Instead of spherical lower shock mount I made a simple insert out of industrial plastic (outside diameter equal to inside diameter of the housing and diameter of hole as diameter of collar screw). And I put one thin plastic shim on each side to prevent rubbing between housing and fork of the shock. It serves well for almost two years now and I don't care at all about water and mud. 

Actually, I do not see the reason why the spherical mount is used in the first place, because the swingarm moves up and down in one plane only.

Hope this might eliminate the seizing of lower mount for good.   

I got it all back together today using the swingarm from a 2004 450SX. Everything seems to work fine but I haven't gotten to ride it yet because it's storming outside.

When you do this job again don't use a hammer.  Go to Home Depot and buy some all thread, washers and nuts.  You can use these parts with an appropriately sized socket to press the bearing/races in or out.  Works like a champ and no risk of cracking a swingarm.

I tried that but It stripped the bolt before the bearing moved. It was seized in there good.

 

I actually wasn't using a hammer when I cracked the swingarm. I was squeezing it with a vice.

Wow! If the bolt or nut strips I would try Acme threaded rod. These are much stronger than standard all thread. You can also find stronger all thread than what is sold at Home Depot.

I used a vice instead. It made no difference as it wasn't coming out no matter what I used.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now