Swingarm Linkage Bearing Options

[uhoh7]

I know this is a perpetual subject, and I've been reading up:

 

Just discovered my swingarm linkage bearings on my 06 TXT pro are hammered. 

 

My dog bones are fine. 

 

Is there a source to replace the need bearings with bushings?

 

If not, is is hard to install the new bearings with the swingarm on the bike?

 

TY so much guys

[lineaway]

 They come off easy enough. Pay attention to front and back. Also the bushings are different front to back. After you re-do it a couple of times it`s easy. You can drive the bearings out with a socket and drive the new one`s in with an old bearing.

[baldilocks]

I just put the dogbone in a vice with a large socket one side that the bearing will fit into and a smaller socket the same size as the bearing on the other

[aussiechris]

The above replies are spot on for replacing the bearings.

 

As for options, I haven't heard of anyone using bushes instead of bearings but there a a couple of options for you to consider.  This is from a post I submitted ages ago but is still current...

 

 

Virtually all of the kits sold by dealers include bearings with separate seals. In my opinion these are rubbish. And yes, I know that's what comes from the factory.

The original bearings are HN1516 which is a full compliment needle roller with a 15mm ID, 21mm OD, and it's 16mm wide. The supplied seals are the same dimensions but 2mm wide. That makes for an overall width of 2+16+2= 20mm.

There are a number of reasons why they fail early. Firstly, the needle rollers have little tits on each end to locate them in the housing as there is no cage. For some reason, in our application, those little tits break off and get in amongst the bearings causing failure. But the main reason is water ingress. Those 2mm seals have a steel shell and that doesn't seal too well in the dog bone as it is so thin.

Furthermore, sometimes the seals just plain fall out of the dog bone. The reason is quite simple. The overall width of the bearing and seals is 20mm, but if you measure the dog bones you'll find they are only about 18.8mm wide. This means (assuming the bearing is perfectly centered) that the 2mm seals have just 1.4mm to seat in. And since the seals have a bit of a radius on the inside, there's bugger all holding them in place.

The bearing you want is a HK1520-2RS (contact a local bearing supplier with that number). That bearing is a caged roller with in-built nitrile seals. It is 20mm wide but even though it is slightly wider than the dog bone, it is all one piece. I've been running these bearings for about 10 years now in various bikes. You can expect 5 to 10 years life out of them compared to less than a year from the standard ones. Price is about the same. Even though the original bearings have more rollers that doesn't help if they're full of rust and mud.

This only applies to the four dog bone bearings. There's another two in the underside of the swing arm with two 3mm wide seals. You can't use the HK1520-2RS in there as the total width will be too wide (40mm vs 38mm total). But those bearings a well protected and don't give as much trouble.

Also, you may have to get the inner rings (bushes, sleeves) off your dealer as the bearing shops seem reluctant to hold them. Gas Gas part numbers are BT27712014 (20x15x8mm) 2 required and BT27712005 (20x15x10) 2 required.

 

Hope that helps,

Chris.

ps. the 5 to 10 year life suggested above is for Australia where it is very dry and includes regular re-greasing.

 

[faussy]

^^ Some good info there.

 

If you want to keep your suspension plush do not get bushes or oil lite bushes, too much friction IMO.

[mcman56]

I have made bushings for Sherco and Gas Gas out of 660 bronze.  There is room to install grease fittings and without seals you can flush the bushings with grease like old usa cars.  This eliminates the need to disassemble to grease.  I notice no difference in friction but am no high level rider either.

[crazybond700]

Thanks for that reply

aussiechris

[uhoh7]

Great replies everyone thank you.

 

I am replacing only the swingarm set, not the dog bones. Parts just arrived:

 

Untitled by unoh7, on Flickr

 

These are the OEM; note plastic insert.

 

Looks like they are holding those needles in place. They come in from the side with numbers and must come out that way i think. I was advised to drift against the numbered side, but wonder if I will end up with some extra plastic in the swing arm.

 

What's the best tactic here?

 

Also should I install bearing first then lube?

 

Sorry for silly questions

 

PS also best tactic to relube the dog bones? Avoiding needles everywhere?

Edited September 23, 2015 by uhoh7

[uhoh7]

OK I'm back in action after some drama.

 

Bearings above are not the usual. No more tiny tips one the end of the needles. And consequently nothing holds the needles in place except that plastic insert. Talked to several knowledgeable people, and all were at a loss as to the plastic insert. 

 

So I learned the hard way:

 

Drift against the plastic. 

 

Don't remove it till the last possible moment. Since the needles are now totally loose you can imagine.....PITA to install in the swingarm. Tophat inserts must go in very slowly. May take multiple tries to retrieve various errant needles. 

 

Luckily I had some practice, as I also went to lube the dog bones and one had the tips shorn off and out came those needles. At first I thought I'd wait for another bearing, and I ordered the HK1520-2RS. But riding weather is good.. I cleaned out the loose tips and put the needles back, and the bearing seemed smooth. 

 

BTW for USA best source is Impact Bearing 1-800-962-4180. They were much cheaper for the same INA bearing and sourced a close supplier to me. They promise short delivery for reasonable rate.

 

I scratch my head as to the logic behind the OEM choice of bearings for this task. 

 

L1038787 by unoh7, on Flickr

Edited September 26, 2015 by uhoh7

[aussiechris]

Glad you got it sorted.  Yes, it's bizarre that they stick with the loose roller bearings.  But in theory, the full compliment bearing should last longer than the caged version.  I remember owning a Montesa 172 Cota which had loose needle rollers in the small end of the con-rod.  Pulling the piston on those bikes was common due to carbon build up.  You soon learn to have rag stuffed in the crankcase when trying to re-install the piston pin through those loose rollers.  You also learn a lot of patience.

 

BTW, Nice countryside where you are.

 

Chris.