Ive been looking into types of bearing ,as my build progresses.Got so confused over the pro's and cons of each type...needle rollers,bronze bushes,metalastic bushes,rod ends,or basic roller bearings!

Modern sports bike mainly use needle rollers, excellent location, good life on a light bike, maybe less so in anything heavier.

Older bikes used nylon bushes, I've upgraded several to phosphor bronze, lubing them is another serviice item, still good location but would be susceptable to quicker wear in a heavier vehicle.

I think netalastic bushes would not provide the location 'stiffness' you need.

What does the arm's donor use? that is probably the best route.

No donor,all scratch built!As I said,Ive found theres pros and cons with each of the types. The needle roller system is popular on bikes generally,but due to the way I am mounting the arm with seperate left and right mounts,ie hasnt got a 'through bolt' from one side to other,it means I cant adapt a kit that can be bought for a bike replacement. To buy the parts separately for the needle roller type of pivot is quite expensive.Im now leaning more to the bronze bush idea(not oilite type ,but old style bronze bushes with the spiral grease groove inside).Then use thrust washers either side .
Trouble is,Im having probs finding a supplier in UK for the bushes.

metalastic will be too spongy,rod ends,in my opinion,too flimsy,basic roller bearings not sure of.

Taper roller bearing set-up. I'm sure the old BMW R100 swinging arm has this and no through bolt/spindle..

Yamaha XS1100 has taper rollers

HTH

Neil

I know little of conventional motorbikes, but I do work with quads a fair bit. Many use taper rollers for the swing arm bearings, Hondas used to use a thrust type ball bearing & at least on one model now use a normal ball bearing on one side of the arm & a needle roller on the other so just one side does the location & the other can float. The needle roller wears out long before the ball bearing.
All of them use a shaft drive with the UJ in-line with the pivot so no through bolts. Most have a stub threaded into the frame sticking through into the bearing which is pressed into the arm. The exception being the ball/needle roller pivoted Honda which has a bolt through clevis on the frame with the bearing pressed into the arm.

thanks guys!......... I see what you are all saying,but when Ive looked at those types(or similar) they all appear to have at least a tube connecting left and right sides,which would transfer the pressure exerted by the pushing of the pivot bolts on to the tapered bearings,but mine will have just 2 arms,with no tube,as I have a transfer box in between.Well,actually there will be a cross bar,but not immediately in line with the rear of the bearings.I have thought of ways of using taper bearings for my application,but it all tends to get complicated with mounting bracket(s) (lugs) that are adjustable horizontally! This is why I thought about using a bush,which is simple to replace,and ,of course a lot less complicated to machine up a holder for!Ill go do some more research and report back.......................