Swing Arm Bearings?

[Racinante]

I have a '91 KX 250 that needs new swing arm bearings. One side is completely solid, but when I pulled the sleeve out of the other side, needle bearings were jumping for their freedom.

First question: Where is a good place to buy new bearings? I was able to take my front wheel bearings to a place in town called "Bearings Inc.". They matched up a new bearing for about 4 bucks! The bearing was identical. The problem is, if i get these bearings out, I won't have anything to bring in to them.

Second question: Can I press the new bearings in myself with a C-clamp and the proper diameter sockets? Like the wheel bearings? Or, should I take it to a shop.

Third question: Does anyone know if there is a kit to replace all the bearings in the linkage. They're all in kinda bad shape, and now would be the time to do it since everything is apart.

Fourth question: How many times can I repeat the word bearing in one thread? ;)

 

[Senior KX Rider]

Pivot Works makes the kit you are looking for. Dennis Kirk shows them in their catalog. You can prolly find them cheaper elsewhere. DK shows a price of $47.99 for the kit. You should be able to change them without special tools

 

[250motoxer]

I just got that kit for my 1988 kx 250.... much better!!! when I took it apart some of the pivot bolts were frozen in the sleeves, they were so bad... some time and work was all it took...for a huge improvement.....good luck

 

[Racinante]

Hey, thanks for the info guys! I found the Pivot Works kit at Midwest Moto for $40.95. Is that the cheapest (excuse me, least expensive) that one could find? I was hoping I could replace all the bearings in the "Unitrak linkage", but that will be a lot more money. Maybe in the future. Thanks again though guys. I love this forum! :aj:

 

[jmics19067]

I beleive they have 3 different kits one for the swingarm one for the linkage and then another kit for the shock. all relativley inexpensive.
the swingarm and and linkage I know they should have. the shock itself I believe they have.

 

[Racinante]

Jmics, They want $38 for the shock kit and $70 for the linkage kit. About $150 for everything including shipping. Not bad, but the problem is, I just sent my engine to Eric Gorr so he could inject a new soul in it. So, I won't have the money to replace everything, for a while. The linkage and shock bearings are in ok shape, but they'll need replaced soon. I wish my bike could go out and get a job to help with it's parts bill!

 

[Mac]

Check this thread for more info and some idea's on pressing bearings.

Swingarm bearing thread

 

[Racinante]

Nice pic there Mac! I assume the rope was there to protect the swing arm from the table. Is that right? So, I just need to be careful to get the right sized socket so that it only contacts the outer race? My Kaw book says to measure the distance that the bearing recesses into the whole, and match that same distance with the new bearing. Should I just make sure the bearing is centered between each side, instead?

 

[jmics19067]

I wish my bike could go out and get a job to help with it's parts bill!

heheheh I know the feeling well!!!!! when the wallet gets shy and you are asking yourself the question what is the least of my worries just make sure you ask yourself the question" will it be a long walk to the truck or will it be a short helicopter ride to the hospital?" if anything could fail. and make your adjustment as needed

 

[Vos Schola]

preventitive maintance

after you get those bearing replaced you should take em out and grease em once in a while. seems like a real pain at the time but it saves alot of money and hassel later on

 

[Racinante]

Just to give you guys a lil' background...

I bought my bike last summer. I've never owned an mx bike before and have always wanted one. I saw this thing for sale in front of a guys house. I rode the bike, and it ran, but not great. The price was awesome so I couldn't pass it up. I talked the guy down to $675! Great price for any bike that runs. It not only fit my budget, but I figured it would be a great education for me. Sometimes I feel like I'm learning too much, though! :scream:

I've replaced the pipe and bought many pilot jets trying to get the thing to idle and not smoke so bad. After much research (no help from Kawasaki dealer, or the local mechanic who I paid $180 to tell me I need a new pipe) I discovered my crank seals were leaking.

That's one reason I'm so pro DRN! I've received so much help from so many people here. I'm trying to give advice to other people, but my knowledge of mx bikes is limited.

After reading (for hours & hours) Eric's site, and feeling like I was in a Rocket Science lecture, I decided to have him rebuild my engine and give me a porting job to help the bike be more trail friendly.

So here I am removing my engine from it's frame, and realizing that the swing arm bearings probably had their last taste of lubricant at the factory.

Thanks for the tip Vos. Trust me, my bike is so excited that it's MINE! She gets all giggley now that she's gettin' all the love and affection she deserves. :)

To jmics: I would much rather replace swing arm bearings than Wheel Chair Bearings, anyday!!!! ;)

 

[Mac]

Originally posted by Racinante
Nice pic there Mac! I assume the rope was there to protect the swing arm from the table. Is that right? So, I just need to be careful to get the right sized socket so that it only contacts the outer race? My Kaw book says to measure the distance that the bearing recesses into the whole, and match that same distance with the new bearing. Should I just make sure the bearing is centered between each side, instead?

Thats not rope it's heat tape.
You need one socket with the same size OD as the race and one with a larger ID to catch the bearing when pressing them out.
When I pressed in my bearings I set them to the depth recommended in my manual, 5mm I think.

 

[Racinante]

Heat tape? I'm a lil' confused. Did you heat up the swing arm for removal, or installation? Kind'uv like the interference fit for the crank bearings?

 

[jmics19067]

If you have access to a oxy/acet. torch this is what I do to replace the bearings. Put your new bearings in the freezer. Swingarm off and everything cleaned well. Measure where the bearings sit, ie. are they one one side ,in the middle , not quite in the middle etc . . Find yourself a bushing driver that fits your needs<socket if need be>. Fire up your torch as hot as it gets <itsa neat trick but it is trcky> if all the needles are out of the race quickly try and draw a line of extreme heat from one side of the bearing to the other. The object here is quick you want to try and heat and expand the race as quickly as possible so as it cools it will shrink and in the mean time the aluminum swingarm is absorbing the heat expanding. Most of the time they will tap right out with a light hammer . If not then turn off the oxygen and cover the area with soot, feed your oxygen to your torch until you get a soft flame and heat the swingarm. When the soot starts to burn off that is as hot as you would want to get the aluminum. If they don't tap out easy now my experience has been you are probably going to be heading to a press now.

Clean up the with a rag and a scothbrite for the tuff crud ,be careful it will be hot shouldnt be hot enough to burn you bad per se but hot enough to make you jump. Cover the outside of your frozen bearings with antisieze and slide in might need a slight tap to your desired measurement. Wait till everything is cool to handle ,clean, grease and install

 

[Mac]

Originally posted by Racinante
Heat tape? I'm a lil' confused. Did you heat up the swing arm for removal, or installation? Kind'uv like the interference fit for the crank bearings?

Heating the swingarm will aid in removal and installation and freezing the bearings will also aid in installation. I heat the swingarm at the same time I'm pressing the bearings. Be very careful with a oxy or propane torch because rapid uneven heating could cause warpage, heat tape heats slowly.

 

[Racinante]

I don't really have access to an acetylene torch. I think I might know some people. But, would a propane torch work? I know it's not as hot. It would be easier to heat more evenly, but will it get the swing arm hot enough?

The bearing in the freezer is a great idea! Thank you guys so much!!!

 

[Racinante]

Never mind! I just re-read Mac's post. I will be very careful to heat it as evenly as possible. Thanks again guys. You have helped tremendously! ;)

 

[Racinante]

Originally posted by Mac


heat tape heats slowly.

I guess I do have another question. Is this a tape that undergoes a thermal reaction, and where should I look for it? This sounds like a safer option than a torch.

 

[Mac]

I....um...borrowed it from work, not sure where to buy it. It runs on 110VAC just plug it in and it gets hot.

 

[Racinante]

Borrowed what from where? If anyone asks I don't know nothin'<wink>

Thanks again for all your help. I shouldn't have too many problems, but you know how that works...

 

[whyz]

Is there something that holds thoses little needle things in there?

I got my sons bike apart(motor is at EG's),started the grease scenerio
and while i was slopping around some of that stuff inside some of those little needle things came out.. So i put it back in and bolted it back on.

After reading this post i'm alittle leary bout what i did..Is it cool?
Any suggestions? Should i replace all of them? I dont know if they are worn,it doesnt feel like it. It's a 97CR80.

Thanks..

 

[Battered Sav]

My experience with hondas is limited but I do recall rebuilding s/arms with loose bearings as you describe, check your manual/dealer but I'm pretty sure thats how they're supposed to be, would still be a good idea to check though. I think the grease " holds them in there" until assembly.
Good luck

 

[Racinante]

I wondered about the same thing myself. Although, my needles were all rusted, and the race was only a fraction of itself. (Not to mention the other side is completely rusted in) I assumed I would find the answer to that once I ordered the kit. I would answer your question whyz, once I ordered the kit, but It's for a Kawi and I don't know if a Honda would be the same.