Which years had ball bearning and which years had needle bearings in the head tube?

If you put the Harley race in the top of the 650 frame, and it wouldn't fit the bottom. Thats what your saying, right.
I think your wrong on that. The races top or bottom on the 650 frame are both 48 mm od. If the bearings you have, the race fits the top it also fits the bottom.
I thought they would would both fit the same too but for some reason the opening in the bottom of the neck appears to be larger than the top. I was just curious to see if anyone had encountered this problem before or knows of any way I could slip a spacer ring in the lower neck to take the play away from the bearing?
Pyramid helped me out with a swap of tripple trees...different unit, but they were happy to help out! I swapped XR250 forks to an XS a few years back. to make a long story short, it wasn't an easy swap.
They did get me bearings that worked with minimal mods to the xs neck....had to open the upper cup .020".
I was just saying they got me the bearings that were closest. Ya may be able to get exact bearings from them or another supplier...
If you are going to get more bearings, get a set designed to fit the 650 neck. Then as I said put the races in the 650 and use the bearings that fit the Harley stem.
doyou have to have the new grease seal when replacing old bearings with tapered bearings on a 1973 model?
If the bearing come with a new seal use it. If it don't use the old one. Unless it's torn up, then a new one is a good idea.
If you are speaking of the rubber seal that fits on the lower tree below the lower race mine was in decent enough shape that I could have reused it. I think actually what I ended up doing was getting a new one from the local yammie dealer for a couple of bucks. The dust seal to the left. Old races top, new tapered ones below.
are the necks on the different years the same length? i am putting a earlier front end on a 81 frame and wondering if i will run into any problems.
are the necks on the different years the same length? i am putting a earlier front end on a 81 frame and wondering if i will run into any problems.

Yeah that's a can O worms. The only real solution is a late model triple, grind the weld off the stem, beat it out of the lower triple. Do the same to your (shorter) stem, swap and weld it in. I've done it, but it's not "exactly" shade tree work. Easier to get a late model front end.
What year "earlier front end" do you have?
What is the best way to remove the old race from the triple tree stem. I have tried to pry up on it and tape it up with a screw driver but it has not budged. Right now it is still on the forks I have not removed the lower tree yet.

Thanks, Nick
Have you gotten the oil seal pulled off? If you work carefully and it is warm it will stretch and come around the race. then you can drive a flat screw driver in the slot and start the race moving. In the past I have used a cut off wheel in the dremel slit the race and binged it with a chisel till it cracked the rest of the way then it comes right off.
Thanks for the tips I did remove the oil seal and tried a screw driver with out any luck. I will take it to the local bicycle shop and see what they will charge me to pull it and if its to high I will cut it with the cut off wheel and use a chisle.

Thanks, Nick
Hey guys, so I'm going really far out on a limb but looking for some info and help with my swap. (please be kind as i'm a bike noob)

So I have an 81 xs650 and getting a donor xs from a friend that has a rear disc i think its an 82? Anyway I'm looking to do a swap with a 2006 Kawasaki 636 front end. I have all the parts here finally but am having some trouble researching the steering stem sizes, neck sizes and bearing sizes. I read through a couple of the threads on here and am just having troubles putting it all together. Terminology and such, i can read it a million times but if i don't understand whats being said it means nothing.

I see the thing to do is the tapered bearing swap what exact measurements would I need to have to find the correct bearings for this? Where do i look for such a thing? Thanks hopefully just asking these questions should get me started looking in the right direction.