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Hi all

Any advice on the best type of replacement swing arm bearings for a 500? Needle roller or PTFE? Best source? Also, will a 350 swing arm fit the 500? I think they are shorter & I was thinking they might quicken up the steering a bit, but does the top shock mount position allow for this ? Any advise would be much appreciated.

Cheers

Gary

Hi Gary,
I replaced my swing arm bearings 6 months ago. Everyone here advised me to go for ptfe or other plastic bushes but by then I had already bought new bushes and pivot from NLM. They were easy to fit, though the bushes do need reaming. The new spindle is different in that there is a grease nipple on each end and the hole in the side of the L/H bush position is no longer used. This is a pain because it makes it very difficult to get the grease gun on there without removing the L/H exhaust header. I don't know if mine was typical, but both the spindle and the bushes were worn and needed replacement, so even if you fit ptfe bushes, you may need a new spindle as well.

I hope that is helpful!

Joe.

Hi Joe

Thanks for your thoughts on this. I've yet to pull the swing arm pivot out of the bike, but have heard that these seem to wear as much as the bushes themselves. I'm unsure if NLM offer the spindle & if so at what cost? I hope to get a bit of time on the bike tomorrow & I'll then be a lot the wiser on what needs replacing. I must say that reaming isn't something I'd be happy doing, so whatever the condition of the spindle I'll be keen to swop to a more maintenance free & easier to install alternative.

That's Plan A , anyway...!

Cheers

Gary

Hi Gary,
NLM have the bushes and the spindle. The spindle wouldn't be difficult to make on a lathe, though it's probably out of the scope of a model-maker's lathe. If you are going for ptfe or similar, your existing spindle will probably be fine after trueing up on a lathe, mine had worn unevenly. If you go for the metal (phosphor bronze?) bushes, the existing spindle will probably be a bit too small after trueing up. I only had to ream the bushes a whisker - about 0.005" if I remember rightly.

Hopefully someone will be along with info on the ptfe bushes, but you'll probably find previous threads on this forum. Good luck with it!

Joe.

Hi Garry

My experience is that it´s often more a question of worn spindle than bushes. Therefore you can try one thing:
Loose the lefthand nut of the spindle, loose the big nut on the right side (32mm?) and then turn the spindle (for example with a 15 mm key) 90° o 180°. Fix the lefthand-nut till there is no notable axial play between the frame and the swingarm an then fix the big nut on the right hand.

If you are lucky the play of the swing arm will disapeare and you can go on some 10-20.000 km/miles without spending a dime. I tried this several times (2x 90°) and often it helps for couple of years.

Maybe it´s worth a try

norbert

I used to do this as a postal service using the old spindle and either I fit Igus Idlidur advanced plastic bushes which do not need reaming or lubricating or I send the re machined spindle and new bushes for you to fit. I have this set up on both bikes and not lubricated in 20years and they still do not have any play. Igus in their blurb recommend water for lubrication but the bushes are fitted 'tight' so that with the spindle movement a deposit of the plastic is deposited onto the spindle so that you have plastic to plastic bearing surfaces. If you are intent on using phospher bronze then with the grease you end up making a nice grinding paste which wears the spindle. The problem with nylon and PTFE is that it is too soft and hygroscopic. The Iglidur 250 material was designed for problem lubrication situations such as farm machinery where farmers do not know what lubrication means - certainly in my village they do not. If you have rearsets then the grease nipples holes are used as one of the location points for the plates so using this plastic makes life so simple. Look up Igus Advanced Plastics, a German firm but they have manufacturing facilities in Northampton.

Hi Harry

I think this is the best solucion, next time I have to deal with the swing arm bearing, I´m gonna go that way as well. Do you remember what material from Igludur you have used? There are quite a lot.