The Hodaka Club Forum

This it what happens when you take something apart and then don,t get back to it for a couple of years.

Do the shorter length threads go into the case ? That would be my guess but I want to be sure.

Does anyone know what pitch the threads are and if they are the same on both ends ?

The reason that I ask is the nuts will start fine on the longer threaded end but not very well on the short end,but it is the reverse when starting them into the case - long threads want to start fine in the case and short side not so much.

I would like to buy a tap and die to clean up all of the threads before assembly.

Very important the long threaded goes into the case, The short is to short. ---Clarence I would not tap and die the threads.

M7 x 1.0 if I remember right. Same on both ends.

I've had to chase many threads with a tap or die, especially after re-plating. Certainly makes assembly easier.

However, I have to partly agree with Clarence. You will not be able to re-tap the case threads fully unless the hole is a through and through. Which means you'll only be able to tap about half the threads before you bottom out. I would definitely chase the cylinder bolts and head nuts though. But, if you end up cutting new threads when cleaning them up, it might be better to replace them. Chasing threads shouldn't require much effort at all.

$0.02

Roger

I believe the threads in the cases and/or the threads on the studs were mfgd to provide for a "snug" fit of the studs in the cases. The intent was help assure that when the head nuts are removed, they break-loose and turn before the studs break-loose and back out of the cases. While this intentional tight fit is not critical, it is there and does serve a small purpose. Therefore, I would recommend running a tap into the case holes only if they actually NEED some sort of clean up. I have to admit that I can't specifically remember which end goes into the cases, so I am fully on-board with Clarence (cuz he KNOWS lots of stuff about the early models for sure). (And that "fits" with the concept of having more threads engaged with the aluminum of the cases for strength). Finally, I would recommend using Loctite on the stud threads as they go into the cases. This serves two purposes. It 1) "locks" them in place and 2) it "seals" the threads so there is no chance of engine leaks at those points (and those threads CAN BE leakage spots). Std Loctite is fine. Torgue the studs into the cases at the same torgue specified for the head nuts.
My 2 cents,
Ed

Thanks to everyone for the help and sound advice.

You need the depth of the longer threaded portion of the head bolt screwed in all the way. Less than that can pull the threads when you torque the head, not fun I have been there.---------Clarence