HarleyTechTalk

So is the consensus still that 0.625" is the go to drill for drilling out the upper push rode tubes for clearance? That leaves very little material at the top, 0.019" wall, or would a 39/64" (0.609") be good enough? 

Honestly, I don't know how one can drill it without a fixture for the tube and one for the bit to keep it all centered.  In other words a lathe.

Quote from: vafatboy1 on May 30, 2017, 04:27:57 PM
Honestly, I don't know how one can drill it without a fixture for the tube and one for the bit to keep it all centered.  In other words a lathe.

Buddy did mine on his lathe with a small boring bar.    Bob

Quote from: vafatboy1 on May 30, 2017, 04:27:57 PM
Honestly, I don't know how one can drill it without a fixture for the tube and one for the bit to keep it all centered.  In other words a lathe.

That's what I used, chucked them up in a 3 jaw and drilled with a 5/8 bit.
About 4K on build now without issues

 I had Donny chuck mine up in his lathe. I had him use a 5/8" bit and had him go in from both sides of the tube. Basically mine were bored 5/8" all the way thru. No issues at all.

The plan is to use a horizontal lathe. Just need to decide on the bit size to order.

Quote from: No Cents on May 30, 2017, 04:42:31 PM
I had Donny chuck mine up in his lathe. I had him use a 5/8" bit and had him go in from both sides of the tube. Basically mine were bored 5/8" all the way thru. No issues at all.

That's my plan Ray, go all the way through.

All you guys with access to the means and knowledge to drill them out should offer a swap out for us poor saps that aren't able to. I'd gladly send my tubes in for receiving a drilled out set. I run the old SE non tapered adjustables with my cams and believe mine are/have been rubbing as I've always had ticking and whatnot.

Simply seek out a machine shop in your area. Nothing tricky, just a lathe needed, and a drill bit.

May sound funny BUT can a small cylinder hone be used to do the job? 
Was reading the post and my Mc Giver went off!!

I think your honing stones would fill with aluminum pretty quick.

The advice to take it to a machine shop is good advice. Shouldn't cost much of anything. Trying to do it by hand with a drill bit is asking to scrap it at best, injure your self at worst.

Quote from: Rockout Rocker Products on May 30, 2017, 06:12:34 PM
The advice to take it to a machine shop is good advice. Shouldn't cost much of anything. Trying to do it by hand with a drill bit is asking to scrap it at best, injure your self at worst.

And scrap in no time at all! 

Can I ask what the ID is prior to drilling? I have never measured.

15.5 mm spade drill in a lathe......works fine

Drilled mine 5/8" by hand. about 10 years ago. & a few cams. & a rebuild. Didn't see the need to drill thru as the witness marks were only near the top. It's not rocket science.

Quote from: koko3052 on May 30, 2017, 09:21:53 PM
Drilled mine 5/8" by hand. about 10 years ago. & a few cams. & a rebuild. Didn't see the need to drill thru as the witness marks were only near the top. It's not rocket science.

Yep.  I only tapered in about the top 3/4 inch with a die grinder.  Not sure why you would need to drill the entire tube.

You don't need to go all the way through, 1-1/2" at the top is more than enough.

Use a 5/8" (0.625") drill bit, yes it's thin at the top, but there is enough there to support the O-Ring and that's all that's needed.


Ancient => A HTT thread on the PR Tube topic  TC Upper Pushrod Tubes

I do them by hand, old carbide masonry, ground down to .61; these won't bite and grab the tube
No need to go .625, all you need to do is take off the flange on the end. Yep not rocket science, not a big deal.

These work pretty well, they don't grab an give a nice smooth finish.

Quote from: FSG on May 31, 2017, 12:41:33 AM
You don't need to go all the way through, 1-1/2" at the top is more than enough.

Use a 5/8" (0.625") drill bit, yes it's thin at the top, but there is enough there to support the O-Ring and that's all that's needed.


Ancient => A HTT thread on the PR Tube topic  TC Upper Pushrod Tubes

Your right Gary, the push rod distance to the tube, due to angle of the push rod as it enters the tube only changes a bit. But the exit end of the tube is where all of the potential contact would occur due to angle changes.   

Quote from: Ohio HD on May 30, 2017, 05:41:02 PM
I think your honing stones would fill with aluminum pretty quick.

I need to check my tubes after I remove the safety wire!! I was under the idea they are THIN plated chrome over steel (SE) not ALUM.
Way more $$$ for manufacturing in ALUM then steel. Ill check with a magnet. Thanks

UPDATE" as the chrome is very thin on the SE tubes (rubs off easy) and the magnet would stuck to the tube I have little time till I can check after a few cleanings. They also come dented (non viewed side only)!! Possible resolution to the push rod problem??

Quote from: Templer on May 31, 2017, 09:35:34 AM

Quote from: Ohio HD on May 30, 2017, 05:41:02 PM
I think your honing stones would fill with aluminum pretty quick.

I need to check my tubes after I remove the safety wire!! I was under the idea they are THIN plated chrome over steel (SE) not ALUM.
Way more $$$ for manufacturing in ALUM then steel. Ill check with a magnet. Thanks

You don't drill the lower chrome tube, you drill the upper aluminum tube.

http://www.harleytechtalk.com/htt/index.php/topic,69838.msg756889.html#msg756889

Only once have I encountered a "maybe" issue. I just happened to acquire a 12" x 5/8" tapered reamer slightly dull that worked a treat on the upper tubes. The motor sounded the same to me,(half deaf), but owner swore it was quieter. Owner wins!!
fwiw  Buffalo