harleyKmodel

Can someone tell me if upper triple tree item 45738-62 will fit my '52 K?
A previous owner welded the handle bar mounts for some reason.

Not if it has the 52-53 bottom tree. You need the early upper clamp or else change out the bottom tree for a later one.

No. The 1952, 1953 and most of 1954 triple trees are "offset" - the fork stem and the fork tubes are NOT parallel to each other. Starting (we think) at 54 KH 2250, and definitely at the beginning of 1955, they changed to parallel triple trees. The -62 won't fit, and neither will any of the parallel ones from late-54 and later.

You can see the difference between the "offset" 1952-1954 and the "parallel" late-1954-1969+ brackets below. What isn't obvious is that on the -52, the holes for the fork tubes are not at the same angle as the hole for the fork stem.




The 1959s used the small headlight, no switches on the upper panel, and the larger speedometer, so the mounting tabs were different. The late 54 to 1958 had a bracket (-54) with the same front tabs as the -52, but it was parallel.

Thanks to everyone. Your feedback saved me a lot of wasted time and money.

The handlebar clamps are welded in place. I think the engine vibration would be unacceptable.
Can I assume that I can change out the ENTIRE triple tree with a 900 Sportster through the 1960's and have a workable combination?
I'm new at this. How can I tell when Harley made design changes that limit interchangeability?

Any 33.4 mm Sportster tree set can be used. You can even swap in Timken tapered bearing sets on them if you want to. The 54 on trees have more trail and the steering is a little slower. You won't even notice it.
Most of "what fits what" is learned through experience but ask on a forum and you'll probably find someone who has already been through it will give you advice.

I have correct -52 Top tree listed on eBay if you have the early bottom. Early trees are different for better straight line stability w K frame 52-53. If you use -54 trees you want the shortest tubes available to match. Otherwise it will be a quick steering slightly high in front ride.

You should probably grab the one on ebay. They are pretty rare and people look for them to run on KR and KR Replicas as well as XLR's.

I have 3. One NOS listed. One missing outer forward tabs one missing inner forward tabs. Easy fixers...Erik seller ekhkhk56