101 Scout... going to take a while

[pisten-bully]

Thanks you guys, I'll see if I can get some other pictures...those are a bit dark!

[PaulCDF]

Harry your cases look GREAT Good to hear you are making progress.

[Steve Swan]

Harry, glad to hear and see more progress! I enjoy and appreciate following your journey!

[pisten-bully]

My engine is finally moving forward! After languishing at one machine shop for over a year with negligible progress, both parties agreed it was too long to sit and so we both decided I should give a shout out to another local. So I contacted Miles Mushlin, you may know him as a specialist in Nimbus four cylinder restorations, but he also ran a highly regarded and successful company producing precision machined parts for various industrial applications. Miles has since retired from his business but is by no means done working! Lucky for me he agreed to take on the challenge of putting this motor back together with a repaired case.

The first steps were to measure and determine what, if any, effect the welding repairs had on the bores and centers of the pinion gear bearing race, the cam bushings locations, the lifter bushings locations, and how everything would match up with the gears and the cover in place. Concentricity was one term Miles used (...and I'm still not 100% certain I fully understand.) Remarkably things measured up very close, and by close I mean we were fortunate to have a second case borrowed from DKGOZ (....thanks Dave!) to use as a type of blueprint.

Today I went over to Miles' shop and he showed me a very smooth turning gear case, it was awesome:

9D6ADF01-9D8B-40A9-B0E6-9686C2A38091.jpeg
Of course it wasn't as easy as putting gears in and mounting the cover! First try and the gears were way too tight, so Miles machined up a new set bushings. I think he finally settled on a third or maybe even fourth set of bushings until he was happy with the movement and gear lash. All the machining done by Juris was consistently .015 over and with the cracking in the case there was one cam bushing that required a bushing center that is visibly offset. But it's very smooth and the cover fits perfectly!

93CEB6CB-F51E-44CE-966E-3179BC2B9C9F.jpeg

Finally!

[TH47Indy]

Nice job! I wouldn't have thought about trying loctite, usually reach for JB Weld for this type of stuff, but I hate using it.

[pisten-bully]

replacing the kicker stud turned out to be a bit of an adventure, the old stud was not original to the bike, it was at least .023 larger than original, so the hole had been "worked", it wasn't fully round and some brazing had taken place at some time:

9EA5B167-305C-4A6F-B5EE-60191F13EE10.jpeg
I got the hole mostly round with a small hone, but the largest stud available is .015 over, or .772 so when Kent Thompson and I talked I had him send me some shim material that he had, along with the .772 stud. On my first attempt I shimmed the hole, but the stud pushed the shim out the rear after it was halfway through. It was tight, but not supported at the kicker end of the stud so I beat it out and started over!

This time I wrapped the shim around the stud along with some Loctite, clamped it over night:
FC4BFB92-A9D0-4F3F-84C0-BF483942B5B2.jpeg

A heavy hammer (using a deep socket on the stud to beat on), and some heat and it's in there to stay I hope!

EF1CA7EB-15C5-476C-8A52-0776B695F46C.jpeg

I had a good conversation with Kent and my point of view was that the stud is not a moving part, it's a solid point that doesn't rotate so shimming should be okay!

[PaulCDF]

Thanks Harry
Would Walkers have any advice?
I am recalling Mike Tomas’ film on removing kicker stuff from 1940s Chief: A lot of heat an a big hammer!

Okay I’ll say it: JB Weld?!?!?!

[pisten-bully]

In the picture the lower part what is that hole for?

Paul, that's for grease, but this offset kicker stud is either home made or from a different engine/frame combo... when I mocked it up I used a wooden dowel in place of the stud to fit the kicker and it all lines up, the stud I'm looking at from Walker's is straight (haven't ordered it yet):

Walker stud.jpeg

So I guess I threw out too many numbers! Basically I'm asking if ~.025 clearance will be snug enough of a fit to serve as the kicker stud installation?

[pisten-bully]

I missed the sectional sketches. The cutout section does have a wider flange. You are correct.
Tom

Thanks Tom, I posed this question on the 101 Association site and received some interesting feedback! Apparently there was a changeover to fender styles from having a full skirt in that area to having a cutout in that area, but there is no documentation (so far) as to when that change took place. My fender is horribly abused in that area but you can see a hint of a crease in the skirt (which I have yet to determine how to duplicate!)


crease.jpg


There are other pictures showing examples of both styles, full skirt and cutout. this picture from Dkgoz shows the skirt with crease best:

Dave's fender.jpeg

[PaulCDF]

Sorry Harry I had to write so my pea brain could ponder which is to say I am lousy
at math:

Original studs were .07575 ??? 0.7575
Original casting hole Unknown.

The hole in the casting measures up to 0.797 (+/-)

The old stud measured 0.775

(T)here is an oversize stud available at .772.

Will 0.772 be tight enough for casting hole of 0.797 (+/-)?

So the stud you have at 0.775 is larger than the available oversized 0.772???
and larger than the original studs at 0.7575??????

Again don't mean to be a PITA just trying to understand. Can the one in your possession be brazed or silver soldered to make a tighter fit (I'm cheap)?

In the picture the lower part what is that hole for?

[Tom Wilcock]

I missed the sectional sketches. The cutout section does have a wider flange. You are correct.
Tom

[Tom Wilcock]

I had a second look at George's drawing on #171 and I think the cutout had the small flange like the rest of the fender. The wide part and the dotted line on it is actually the other side of the fender which can be seen past the cutout portion.
Tom

[Tom Lovejoy]

fantastic save on those cases, really impressive ! enjoying this thread, great job so far

[pisten-bully]

This 101 frame came with an offset kicker stud installed, so I need to get a new one. The old stud measured .775 and there is an oversize stud available at .772. Not being sure what sort of clearance is typical for these so I am wondering if .772 will be tight enough? The hole in the casting measures up to .797 (+/-) so that would give me approximately .025 clearance between stud and frame casting hole. Original studs were .07575 and I don't know what the casting hole was originally. So what sort of clearance should I aim for to achieve a solid press fit?

stud.jpg

[exeric]

That kind of sheet metal work takes a lot of patience, and real dedication to achieve the result you want. I think it's amazing how you learn where to tap, and how to make the metal move where it needs to go. Beautiful work, Harry.