[pan957]

Has anyone ever renewed the 1/2 hub [3/8" axle] bearing path and brake drum surface on a Harley 45 WL ? I have rust pits in both side of my bearing surfaces where the ball bearings run and the brake drum inner surface where the brake shoes contact is heavily pitted. I worked in a machine shop for 3 years running a surface grinder and we dressed grinding stones to various configurations. My idea is to grind a shaft mounted dressed round grinding stone and gently renew the bearing races on a milling machine. For the inner brake drum surface I would assemble the inner bearings and hollow center shaft assembly and spin the drum/spool hub assembly on a lathe and retrue the inner drum surface. I would buy a new center hub assembly but OEM Harley hubs are $850 and I don't trust the ones from Tedd Cysle/ V-Twinn to be made correctly or the bearings races to be hard enough. Any thoughts or experience is welcome.

 

[pan957]

I know nothing about the hub of which you speak. Pics would help.
I’m assuming it uses free balls and not press in ball bearings.

Mounted point grinding wheels in a milling machine spindle won’t have the required speed (SFM) or bearing rigidity. A bearing race with chatter is worse than a bearing with pits. Are you using an auxiliary high speed spindle, mounted to the quill ?
What kind of dresser will you use to generate the radius on the point and do you have an optical comparator to check your result Or a good enough CMM ?
Will you mount the hub to a rotary table or are you using a CNC mill ? If you have access to a mill…do you also have access to a good lathe and tool post grinder ?
Will you use oversized balls and where will you source them ?
Bearings are magic and have JuJu. They don’t allow compromises. At least for very long.

I’ve been machining stuff for 55 years. You’re asking questions. I’m asking some too.
Together, maybe we can figure this out without ruining anything or putting your life in peril.

As for the drum, remember it needs to be laced up and trued when you’re resurfacing and then you want to radius your shoes to match the result.

Way back in ‘79 I tried re-facing my single side ‘54KHK front hub. Chucked it up in a lathe with a tool post grinder. Got it dial indicated concentric with the axle. Blued the inner drum surface and just cleaned it up to perfection. Got a brand new set of Buchanan spokes and laced it up to a 21” rim. On the truing stand you could see the warps and ripples in the freshly ground drum as the truing process torsioned the drum out of round/true. I still have those spokes.
The road to Hell is paved with good intentions.

I salute your intention to save this part and keep it original.

I know nothing about the hub of which you speak. Pics would help.
I’m assuming it uses free balls and not press in ball bearings.

Mounted point grinding wheels in a milling machine spindle won’t have the required speed (SFM) or bearing rigidity. A bearing race with chatter is worse than a bearing with pits. Are you using an auxiliary high speed spindle, mounted to the quill ?
What kind of dresser will you use to generate the radius on the point and do you have an optical comparator to check your result Or a good enough CMM ?
Will you mount the hub to a rotary table or are you using a CNC mill ? If you have access to a mill…do you also have access to a good lathe and tool post grinder ?
Will you use oversized balls and where will you source them ?
Bearings are magic and have JuJu. They don’t allow compromises. At least for very long.

I’ve been machining stuff for 55 years. You’re asking questions. I’m asking some too.
Together, maybe we can figure this out without ruining anything or putting your life in peril.

As for the drum, remember it needs to be laced up and trued when you’re resurfacing and then you want to radius your shoes to match the result.

Way back in ‘79 I tried re-facing my single side ‘54KHK front hub. Chucked it up in a lathe with a tool post grinder. Got it dial indicated concentric with the axle. Blued the inner drum surface and just cleaned it up to perfection. Got a brand new set of Buchanan spokes and laced it up to a 21” rim. On the truing stand you could see the warps and ripples in the freshly ground drum as the truing process torsioned the drum out of round/true. I still have those spokes.
The road to Hell is paved with good intentions.

I salute your intention to save this part and keep it original.

 

[pan957]

Thank You for your input. The first picture is of the brake drum swept surface of the 1940 WL Solo front wheel. [sewer pipe interior surface]. The second pic is of the spool side bearing race surface with fine pits.The third pic is of the brake drum side bearing race surface with fine pitting.I have decided to proceed as follows: Grind off the existing rusted brake drum rivets and discard the drum. Purchase a New Old Stock WLA military brake drum and rivet it to the the hub. Install new ball bearings with a good used front wheel axle sleeve, grease it well and run it. The pits are not real bad but the front drum is junk. I think with a little blacksmith rivet work I will be ok.

 

[pan957]

 

[pan957]

3923-30 is the right side bearing race and threaded adjuster. 3921-30 is the left side axle sleeve with the outer bearing race formed to the shaft. A 3910-30 3/8" "pencil" axle goes thru the hollow center of the axle sleeve and is nutted to the springer front fork rockers. I know it's confusing but it is 92 year old technology. It wouldn't be fun if it wasn't a challenge. Harley used these parts on their 45" RL & WL flatheads from 1930 to 1952.

 

[pan957]

If you take off enough material to get rid of the pits, would the races then have too much play for the balls? Or can you source oversize ones? And (not knowing anything about stuff this old) are they plated, heat treated, etc., and how would you restore that?
You sound like you know what you're doing, but just thought I'd give this a bump 🙂

I decided to just clean the races and run them. Path of least resistance. The Brake drum is going to be replaced. See my other replies ti Tim.

 

[pan957]

Since we're asking questions. How about sending some pictures? Is this bike going to be road very far, like 1000 miles, or just a couple of miles to the watering hole? What I'm getting at is assuming not far, I would assemble the hub with new balls after cleaning the races and feel it. It maybe good enough for your needs.

Good idea! See my reply to Tim The Grim.

 

[pan957]

Are you on a tight budget ?
Surely new old stock complete hub exists ?
Do it right once.

Yes I am. The only NOS one I found was $850!!

 

[pan957]

45 Restoration is a reseller for Taiwanese stuff from Tedd's Cycle V-Twinn. Although a lot of V-Twinn parts are ok I don't trust any parts from them with a bearing surface as they tend to be soft and dimensionally inaccurate.

 

[pan957]

I know nothing about the hub of which you speak. Pics would help.
I’m assuming it uses free balls and not press in ball bearings.

Mounted point grinding wheels in a milling machine spindle won’t have the required speed (SFM) or bearing rigidity. A bearing race with chatter is worse than a bearing with pits. Are you using an auxiliary high speed spindle, mounted to the quill ?
What kind of dresser will you use to generate the radius on the point and do you have an optical comparator to check your result Or a good enough CMM ?
Will you mount the hub to a rotary table or are you using a CNC mill ? If you have access to a mill…do you also have access to a good lathe and tool post grinder ?
Will you use oversized balls and where will you source them ?
Bearings are magic and have JuJu. They don’t allow compromises. At least for very long.

I’ve been machining stuff for 55 years. You’re asking questions. I’m asking some too.
Together, maybe we can figure this out without ruining anything or putting your life in peril.

As for the drum, remember it needs to be laced up and trued when you’re resurfacing and then you want to radius your shoes to match the result.

Way back in ‘79 I tried re-facing my single side ‘54KHK front hub. Chucked it up in a lathe with a tool post grinder. Got it dial indicated concentric with the axle. Blued the inner drum surface and just cleaned it up to perfection. Got a brand new set of Buchanan spokes and laced it up to a 21” rim. On the truing stand you could see the warps and ripples in the freshly ground drum as the truing process torsioned the drum out of round/true. I still have those spokes.
The road to Hell is paved with good intentions.

I salute your intention to save this part and keep it original.

Has anyone ever renewed the 1/2 hub [3/8" axle] bearing path and brake drum surface on a Harley 45 WL ? I have rust pits in both side of my bearing surfaces where the ball bearings run and the brake drum inner surface where the brake shoes contact is heavily pitted. I worked in a machine shop for 3 years running a surface grinder and we dressed grinding stones to various configurations. My idea is to grind a shaft mounted dressed round grinding stone and gently renew the bearing races on a milling machine. For the inner brake drum surface I would assemble the inner bearings and hollow center shaft assembly and spin the drum/spool hub assembly on a lathe and retrue the inner drum surface. I would buy a new center hub assembly but OEM Harley hubs are $850 and I don't trust the ones from Tedd Cysle/ V-Twinn to be made correctly or the bearings races to be hard enough. Any thoughts or experience is welcome.

A NEW APPROACH TO THE WL 750cc FRONT BRAKE SITUATION.
I obtained a used front 16" WL wheel with acceptable ball bearing race surfaces, good original paint rim, bad rusted spokes and a badly rusted 1/2 brake drum. It took me 8 hours with a heat gun and PB Blaster penetrant to unscrew all the spokes. I did not want to cut the spokes off with bolt cutters as I wanted to save them for a static wheel display made of junk parts. I drilled out the 5 rivets holding the brake drum to the spool hub flange without egging the spool hub rivet holes. I obtained a NOS green front USGI WLA brake drum off of Ebay. QUESTION? Has anyone ever riveted a front WL brake drum to a front spool hub. I'm thinking of using 3 tight fitting bolts and nuts in 3 of the rivet holes to clamp the drum tight to the spool hub flange. I'll then true up [centralize] the drum to the spool hub using a HD trueing stand or a lathe. I'll loosen the bolts and nuts slightly and tap the drum around until it is as centered as much as possible. I'll then tighten the nuts and bolts, heat up 2 rivets red hot and peen them in the 2 vacant hub/drum holes. Then I'll remove one at a time each of the 3 remaining bolts and nuts and rivet the 3 remaining rivets home. Any experience or suggestions?

 

[pan957]

How tight a tight spot on the chain? Chains and belts always have tight spots. I always spin my primary chain and mark the tight spots with paint or red nail polish. That way in the future I only have to check/adjust in that area. Adjusting in the loose area of a chain or belt causes premature wear and robs power. You can feel the difference in low powered Harleys when you accelerate.