First Rebuild/chopper Build

[Jac0b561]

Hey all, first off I am using parts that have been sitting around people's yards and am cleaning them up to turn into a chopper. So nothing is going to match serial number wise. And no worries about me tearing up an old classic haha. The engine is pretty much going to stay the same. The S/N on it says DU55201 which I believe it to be a 1967. I've cleaned it up pretty good but noticed the hole's threads on both sides of the engine case are pretty shot on a couple places. (I may have hurt them a bit more myself with a thread chaser).

First one is on the left side crankcase for the "Tachometer Drive Plug" item number E4706, or just Tachometer pictured below. And the second is for the right side bottom for the "Drain Plug with level tube" item number T1112.

I need some good advice on what I should do to fix it if possible. The only methods I can think of are three and that's either Helicoil, plug weld and re-drill and tap it to spec or the last which I hope I won't have to do is buy a whole new case. I have access to a machine shop (I am learning the trade), a welding shop (already did two years of schooling but they'll still let me weld if needed), and I know my local motorcycle shop for when things get a bit to stressful I can always take it to them. But I try to do things myself before throwing money at them.

Also I am having a hard time finding it, but I can't seem to find anything on bolt specs, does anyone know of where I can find what size all of these bolts are, threads, pitch everything?

Also since this is my first build I will probably come back here as well with more questions I am sure, so bear with my noobiness. haha

Now here are the pictures.

 

[Rocky]

Grandpaul is probably the best person to offer advice since he has been in the restoration business.
He should show up later.

 

[grandpaul]

Howdy, Jacob (?) and welcome to the forum.

You'll likely need to install helicoils, they are readily available in British threadform.

There are some thread charts available, I'll see if I can find a link. You can start by internet searching "British motorcycle thread chart" and it's quite likely to come right up for you.

Anything you need in the way of parts, I can provide at very reasonable prices; however, I need to operate in medium-large orders or it's not worth my time (very slim profit margins available these days). I do have some decent, serviceable used parts on hand.

 

[Jac0b561]

Howdy, Jacob (?) and welcome to the forum.

You'll likely need to install helicoils, they are readily available in British threadform.

There are some thread charts available, I'll see if I can find a link. You can start by internet searching "British motorcycle thread chart" and it's quite likely to come right up for you.

Anything you need in the way of parts, I can provide at very reasonable prices; however, I need to operate in medium-large orders or it's not worth my time (very slim profit margins available these days). I do have some decent, serviceable used parts on hand.

I guess I'll try the helicoil route then. It is the more traditional route from what everyone uses. I did like my idea of plug welding the holes then drill and tap back to normal again. But I'll do it the regular way haha. I checked the threads with a thread pitch gauge luckily both holes are 16G, BSW. But while I have your offer on parts, do you happen to sell old vintage wheels as well? I am looking for a very particular wheel. One made by a man named Scotty with "Scotty's Invaders". The one I am looking for is a 10 spoke, drum brake, Honda CB750 rear wheel. I actually emailed him a few months back and he said he doesn't make those style anymore. So my only luck is through other salesmen.

 

[grandpaul]

I had an Invader 8-spoke chrome wheel some years ago, no more.