Re-Furbishing 3 Piece Racing Wheels

[Swift17]

Ok ... I need the final "truth" when it comes to the process and material(s) to be used to refurbish and re-coat (paint?) racing wheels. I have four (4) full sets of Jongbloed #215 wheels which this past weekend I removed the centers (all 288 nut, bolts and washers ) from the rims – This weekend I will be stripping off paint, using " ______________________________" [aircraft stripper, paint remover ? ] and then getting them "blasted" by " ____________________" (please insert soda, or plastic, walnuts or other media [ I know NOT sand or glass]). Then to crack testing at a NDT* Service- When done do I "buzz bomb" them with " ____________________________" (Home Depot, Eastwood stuff?) - spray gun with " ___________________" (epoxy, PPG something ?) and then do you clear coat for ease of maintenance , with " _____________________" (paint, etc.) I have searched the forum and again the consensus seems to be NO POWER COATING. Afterwards, re assemble with new Allens and metal locking nut (w/ Loc-Tite ?). Use and seal with Dow Corning Silicone Adhesives/Sealant 832 ([a] on the flat bolting surface AND on the crease AFTER the wheel is assembled OR [b] just on the crease aftre assembled -- Hardware: the wheels have these what appears special Allen headed bolts that are tapered and are wider at the bottom (a source ?). How about one clear thread with experienced comments ?

Non-Destructive Testing service/quoted $20.00 per center,

[Swift17]

Forgot to add the wheels are all currently painted with a buzz bomb ...

EJ

[Steve Demeter]

Dave W uses and probably knows more about Jongbloeds than anyone but Bill.

check with him.

[Joefisherff]

Same wheels, Dave W provided me with guidance. I bead blasted mine to remove the oxidation and old paint. Your procedures are good up to the point where you are sealing them and Dave recommended NO sealant on the mating surfaces only a bead after assembly to avoid them pulling up unevenly. I used the reflective gold by Rustoleum - 2 coats on each center section and then followed that with two coats of clear Rustoleum. The clear dulled the very bright gold just the right amount and eased maintenance. For the outer rims I had to use some sandpaper to get some of the oxidation cleaned up using progressively finer sandpaper until it was at 1000 grit. Then I used the buffer to polish them up. Finally used the Powerball and polish to finish shining them up. Not too bad to do while they are unassembled. I painted the bolt heads to match and keep them from degrading. Ask them where you buy your bolts what the recommended torque is for the bolts. I used nylocks and loctite. Here is a pic of the finished product, I wish I had a before picture I don't think they had been cleaned in years...

[Swift17]

Hey Joe thanks for the info (and to Dave W) BTW that is the wheel (#304) that were all cracked and the hub blew out at Road Atlanta turn # 1 !!! Do you have a extra 304 (cracked is ok) to make tow wheels ?

EJ

[Joefisherff]

Yes that was one of them, unfortunately. I do have an extra center that was cracked and welded by the the previous owner that is yours for the taking. I don't have any extra outer rims unfortunately. Let me know if you want it and I will get it sent out to you.

Joe

[Swift17]

... PM sent

EJ

[R. Pare]

When we redid the Jongbloed wheels on DW's old car (when Ken Johnson owned it), we had the centers bead blasted, and then painted with PPG DP90 primer and then a gold epoxy enamel.

The rims were polished by spinning in the lathe - 600 grit sandpaper, then progressively finer scotchbrite, then Autosol. They were then bright dipped and clear anodized - the bright dip reduced the shininess a bit, but they still looked great. The anodizing makes them really easy to keep clean.

I was a bit sceptical about how the rims would far after anodizing ( because of the reduced fatigue resistance), but so far so good.

[Larry]

There you go again, confusing me with facts! How does anodizing reduce fatigue resistance? I thought anodizing may make aluminum a bit more brittle, but thought it would be a good trade due to lack of corrosion...Please 'splain it to me.

Larry Oliver
International Racing Products

[DaveW]

Same wheels, Dave W provided me with guidance. I bead blasted mine to remove the oxidation and old paint. Your procedures are good up to the point where you are sealing them and Dave recommended NO sealant on the mating surfaces only a bead after assembly to avoid them pulling up unevenly. I used the reflective gold by Rustoleum - 2 coats on each center section and then followed that with two coats of clear Rustoleum. The clear dulled the very bright gold just the right amount and eased maintenance. For the outer rims I had to use some sandpaper to get some of the oxidation cleaned up using progressively finer sandpaper until it was at 1000 grit. Then I used the buffer to polish them up. Finally used the Powerball and polish to finish shining them up. Not too bad to do while they are unassembled. I painted the bolt heads to match and keep them from degrading. Ask them where you buy your bolts what the recommended torque is for the bolts. I used nylocks and loctite. Here is a pic of the finished product, I wish I had a before picture I don't think they had been cleaned in years...

Sealing - the bead after ass'y does three things: a) makes it MUCH easier to assemble without fighting a gooey mess, b) allows the ass'y to be torqued w/o anything in between to compress later and loosen the bolts, and c) the after-assembly seal applied to the joints is wider, and therefore has more compliance and is less likely to leak when the parts flex. I used Dow 832 sealant - tough and good adhesion to almost anything. It also is easy to spread and doesn't "skin," (it cures gradually all the way through) so you have plenty of time to work with it after application.

When you paint them, it helps a bunch to heat the centers a bit before painting (on an old industrial hot plate in my case, just hot to the touch) to dry the paint faster and prevent runs. I wish I had used clear over the gold - I will have to paint mine again in a year or two - they're getting permanently discolored by brake dust, etc.

[R. Pare]

Anodizing, being hard and also very brittle, cracks easily when stressed. Once it cracks, it acts as a stress riser to the parent material, and the crack will continue right on through.

Bolts: When we refurbished those wheels, we aslo seitched to Unbrako socket head cap screws with 12 point jet nuts and MS washers. We had the nuts and cap screws yellow zinc plated for looks and corrosion protection.

[Swift17]

On Saturday when I paint - it will probably be 95 (" .... feels like 105" - I LOVE that weathermen comment ) -- I'll lay them out on a steel plate and they will get nice and toasty - Yup ' Ill used the clear as well -

EJ

[jdp526]

I would follow Mr Pare's advice and use the PPG DP series of epoxy primers and follow up using a PPG acrylic urethane paint with hardener to produce a very strong durable finish. You can use a single stage that doesnt require clearcoating if you want to save some time/money.

[Swift17]

My "other" set of wheels (the "cracked" 304's - all of them) seemed to have thicker paint and that may have contributed to me not seeing the cracks [now with really good inspection and with some magnification I saw that ALL four wheels (and at least three or four "legs" per wheel - one with five) are cracked]

Is the suggested epoxy primer of sufficient thickness with the coat of paint to mask cracks (hey watching your son fly off at turn one at Atlanta on three wheels does make you paranoid) - that appears to be the reason I have read NOT to powdered coat wheels - yet many racing bicycles are powdered coated, stating that the cracks will show immediately through in the "bonded" coating ? "buzz bombs" are easy for me BUT if I have to pay a paint shop to shoot them I will.

I am still troubled that all the 304s were cracked - the rims/inners and outers look to be in exceptionally good condition having NO evidence of a hit , scraping or bumping and the wheels and the rims when spun on a tire balancer spin extremly true - Are the numerous and/or overagressive mounting cycles the only explaination as to why ALL four are cracked? My son a mechanical engineer and I would like to understand the cause (I saw -- he experienced the effect) of failure. We just cannot accept " ... they are just old"

BTW the soda blasting was NOT sufficient to remove all of the paint and the surface oxidation on some of the wheels so a "slight" re-do on some with super fine sand at HIGHLY reduce pressure (35 lbs) was used.

EJ

[jdp526]

EJ, the 'epoxy' paints aren't really any heavier than other automotive-types of paints. They are much more durable though than the skakeanspray varieties. You can use auto acrylic enamel with a generic hardener or an acrylic urethane/hardener for your topcoat.

You can easily paint rims yourself with auto paints if you have an air compressor and spray gun. The small touch-up gun may large enough to spray the center sections and you can buy a cheapy repro from Harbor Freight for about $30. Just be sure to use a respirator, nitrile gloves, and have plenty of air circulation. You can do a decent job spraying outside of your garage so you dont fill up garage shop with fumes and overspray.

[DaveW]

My "other" set of wheels (the "cracked" 304's - all of them) seemed to have thicker paint and that may have contributed to me not seeing the cracks [now with really good inspection and with some magnification I saw that ALL four wheels (and at least three or four "legs" per wheel - one with five) are cracked]

Is the suggested epoxy primer of sufficient thickness with the coat of paint to mask cracks (hey watching your son fly off at turn one at Atlanta on three wheels does make you paranoid) - that appears to be the reason I have read NOT to powdered coat wheels - yet many racing bicycles are powdered coated, stating that the cracks will show immediately through in the "bonded" coating ? "buzz bombs" are easy for me BUT if I have to pay a paint shop to shoot them I will.

I am still troubled that all the 304s were cracked - the rims/inners and outers look to be in exceptionally good condition having NO evidence of a hit , scraping or bumping and the wheels and the rims when spun on a tire balancer spin extremly true - Are the numerous and/or overagressive mounting cycles the only explaination as to why ALL four are cracked? My son a mechanical engineer and I would like to understand the cause (I saw -- he experienced the effect) of failure. We just cannot accept " ... they are just old"

BTW the soda blasting was NOT sufficient to remove all of the paint and the surface oxidation on some of the wheels so a "slight" re-do on some with super fine sand at HIGHLY reduce pressure (35 lbs) was used.

EJ

I painted with rattle cans (buzz bombs?) of Rustoleum Gold. One of the things Bill Jongbloed told me back in the day when he, himself, made all the Jongbloed wheels, was "NEVER use heavy, elastic paint. It hides cracks."

While I have never had a crack in all the years I have used Jongbloeds, the cracking you have seems to me to be a result of hard use, not abuse during mounting, etc. Where, exactly are the cracks? Do you have a photo? I am guessing they are a result of some stress concentration maybe caused by over-agressive machining during the manufacturing process, or afterward to lighten them more.

[swiftdrivr]

Didn't chime in earlier so I wouldn't hijack your thread. Anybody know anything about these wheels? they came with the car 15 yrs ago. One is marked 215, and is gold front and back. The other is silver on back. I would guess the 215's had a more compulsive painter, as opposed to a Magnesium vs aluminum center. Does NDT really tell you they are safe? I've heard they don't necessarily crack before failure. Any idea of the expected life span of this type of wheel on an FF? Who does NDT?---Jim

PS: what's a buzz bomb?

[Swift17]

215s - From what I understand these were internal designation numbers assigned to wheel designs by Bill Jongbloed - I am sure Dave W can enlighten us. I have three (3) different configeration for the four (4) sets I have - One set has eight "lung holes" (like your's pictured) , one set has only four "lug holes" and the final two (2) sets have four "lung holes" and four drilled holes to me done as weight reduction. ( I get my camera back tonite and will post pics ) Hey Dave W are these ally or mag ?

In 1986 Louis D'Agostino, Richard Lee and I bought all the cars and spares from Smith Brothers Racing ( Oregon - Evergreen Aviation - http://www.evergreenaviation.com - 'Spruce Goose' owners and rumored US covert-ops air transport co. -- they have their own SR 71 Blackbird [on loan from USAF] in their own Museum and sell drone aircraft !) and each of the three (3) cars were delivered with two (2) sets of 215's [in the third configuration] and one spare rim as well as the original Centerlines for rains) -- I have seen several DB-1s with these wheels especially from the West and MidWest - obviously they were very popular.

Buzz Bomb - A lot of comment on this !! In the the coal mining region of PA and when I was young, aerosol paint products in pressurized cans were call "Buzz Bombs" I guess a carry over from the WWII V-1s era due to the noise as emitted and the spray pattern - a WWII vet introduced me to that name in about 1963 -- rumored to EXPLODE if not disposed of properly "... do not burn ") when I moved to Fla and was working for the first time in a race shop someone asked me for a "gloss black rattle can" and I was lost.

Another "geographic" difference -- Carbonated drinks beverages like Coke in say, South Central and Western PA is called "Pop" -- in Northeast PA is called called "Soda" --

EJ

[DaveW]

215s - From what I understand these were internal designation numbers assigned to wheel designs by Bill Jongbloed - I am sure Dave W can enlighten us. I have three (3) different configeration for the four (4) sets I have - One set has eight "lung holes" (like your's pictured) , one set has only four "lug holes" and the final two (2) sets have four "lung holes" and four drilled holes to me done as weight reduction. ( I get my camera back tonite and will post pics ) Hey Dave W are these ally or mag ?...

I am not that familiar with most of Jongbloed's wheel numbering logic. I only know what I have had.

I'm pretty sure all Jongbloeds had mag alloy centers.

[DaveW]

Didn't chime in earlier so I wouldn't hijack your thread. Anybody know anything about these wheels? they came with the car 15 yrs ago. One is marked 215, and is gold front and back. The other is silver on back. I would guess the 215's had a more compulsive painter, as opposed to a Magnesium vs aluminum center. Does NDT really tell you they are safe? I've heard they don't necessarily crack before failure. Any idea of the expected life span of this type of wheel on an FF? Who does NDT?---Jim

PS: what's a buzz bomb?

FWIW, I don't think the wheels in the 2nd pic are Jongbloeds, because all the JB's I have seen have the center area like the 1st pic. Of course, just because I haven't seen them, doesn't mean he never made them like that.

Life span is indeterminate. It depends on usage, damage, etc. I've used them since the early '80's, and have never had one of the centers fail. I'm still using Jongbloeds that I started using around 1990 (I think these are cast with the # 202). Some of them have made it through some pretty severe wrecks. These have wide (in the circumferential direction) spokes, similar to your 1st pic,

You CAN do NDT yourself - there are dye-type crack-check kits available at most bearing houses, McMaster-Carr, etc. I have NEVER seen a Jongbloed mag center fail instantaneously w/o a severe impact. There are always cracks that propagate, and when they get large enough the wheel fails. The key is seeing them when they are small. Thick paint can hide them from view, and even dye-check kits can be fooled by paint.

Dye-check should be done in an un-painted item, both for accurate detection, and ease of cleanup. Dye-checking is messy.

A thing to be aware of in dye-checking: porosity, machining marks, etc. can give false positives similar to a crack. Some level of judgement is necessary - it's not a fool-proof system.

[Swift17]

See the attach per numerous inquiries inc. DW

[DaveW]

See the attach per numerous inquiries inc. DW

Look VERY closely at the crack surfaces. You can easily see the smoother areas where the cracks had been propagating for quite a while. The very rough areas are where they finally broke when the stress level on the remaining un-cracked material due to the cracks got too high. And, since all these cracks are in similar areas on all spokes, it appears like these all started at the position of highest cyclic stress combined with stress concentrations due to surface roughness, and possibly, porosity.

Usually, the inner portions of the spokes see their highest loads in compression (which, by itself, will not cause cracking), during cornering. However, cyclic loading (once per wheel revolution) can cause cracking, even if the tensile component is small, when combined with high compressive peaks. What were these wheels used on? Only FC's, or were they on an FA, etc.?

However, I also see signs that these cracks may more likely have started due to braking stresses (smooth crack areas on one of the wide faces of the spokes. This actually makes more sense than cornering loads, since the spokes are less thick in this direction, and braking on rough surfaces can cause VERY high tensile stresses on these faces.

Bottom line: given the spoke type (wide in-out, and narrow fore-aft) and the presence of smooth crack areas on ONE of the wide faces of some spokes, I believe the problem was initiated by braking stresses.

[DaveW]

Added more info in post #20

[swiftdrivr]

To get the facts organised, I've redone EJ's original post with what I think are the answers given in the thread. [Still no info on paint stripper.]

The final "truth" when it comes to the process and material(s) to be used to refurbish and re-coat racing wheels.
Remove the centers from the rims –
Strip off paint, using " ___NO ANSWER YET____" [aircraft stripper, paint remover ? ]
Get them "blasted" by " _SODA [ NOT sand or glass]).
Then to crack testing at a NDT* Service- OR AT HOME
Paint them with " DP90 and EPOXY
Then do you clear coat for ease of maintenance ,
NO POWER COATING.
Afterwards, re assemble with new Allens and metal locking nut (w/ Loc-Tite).
SEAL with Dow Corning Silicone Adhesives/Sealant 832 on the crease AFTER the wheel is assembled ONLY
Hardware: the wheels have these what appears special Allen headed bolts that are tapered and are wider at the bottom (a source ?). How about one clear thread with experienced comments ?

Any suggestions for safe / appropriat strippers? [Not Fanny Fox.]
Bolt source?
Is the rest of it right?

Jim

[DanW]

I have used both the aviation paint strippers and Jabsco paint stripper from the hardware store on my oringinal cast mag wheels.

Look at the MSDS furnished. Both of the chem strippers I used contain methlylene chloride, a hydrocarbon that washes off with water. Use an organic/acid vapor respirator and apply outdoors. Soda blasting or walnut shells should require a hepa respirator. you never know what they were originally treated/coated with.

I initally did a dye penetrant test and found no apparent indications, so I took the wheels to a local aviation ND inspection company. They x-rayed and dye penned them for me. I used Alodine, a chromate conversion coating process, then a coat of clear. Again, use an organic vapor respirator. DPL90 (lead free) is a very good primer.

I still have a pint of Alodine if you want it for the cost of shipping. Otherwise, its available from Aircraft Spruce.

Do you have the 12pt capscrews with the tapered heads? Check with Keith at Averill or one of the other forum sponsors. If they are this type, you must also use the special matching washer that is beveled to accomodate the radiused underside of the bolt heads. The 12 point jet nuts that go on the back are self locking. Carroll Smiths "Nuts Bolts and Plumbing" (also known as 'Screw to Win') and the original Prepare to win explain this in much better detail. If you don't have these books, get them.

Of course, I can be completely wrong.

Regards,
Dan Wise

[swiftdrivr]

Thanks, Dan. I'll Take you up on the Alodine. [PM to be sent as soon as I remember how.] Thanks to Dave and everyone else too. The advise from these forums has been a lot of help this year.---Jim

[Swift17]

Following up on Dave W's question, these wheels had their entire life on Swift DB-1 FF the original car then mine ....

EJ

[DrJim]

Sure looks like those wheels are made from sand casting molds.

I would look at the casting process. If the sand did not break down during the solidification prrocess, the outer rim would be constrained and as the inner part shrunk, the metal in the spokes was stretched and "weakened".

Just another reason not to like sand castings.

[DaveW]

Following up on Dave W's question, these wheels had their entire life on Swift DB-1 FF the original car then mine ....

EJ

Then it's pretty certain that braking stresses, plus any casting flaws, were the reason(s) for the cracking.

[DrJim]

Dave, you comments raise an interesting question.

Are the damages due to lateral or braking forces?

Braking forces would create a tortional force about the axle generated by the brakes. Would not this force be carried by every spoke near equally?

On the other hand, lateral force on the contact patch is carried by one spoke with the help of its two neighbors. If the logic is valid, then lateral force creates from 3 to 9 times the load on a spoke as does braking force. Now the geometry favors the spoke handling more lateral force - not sure what that number is.

My experience with my FF is that the max lateral G's I've ever seen on my data system was 1.8 compared to 1.3 in braking.

So, I stand to be educated.
Wishing you well.

[DaveW]

Dave, you comments raise an interesting question.

Are the damages due to lateral or braking forces?

Braking forces would create a tortional force about the axle generated by the brakes. Would not this force be carried by every spoke near equally?

On the other hand, lateral force on the contact patch is carried by one spoke with the help of its two neighbors.
Not true. The cornering force is distributed, with the help of the rim sections, over a majority of the spokes. Of course, this is not a uniform distribution, since the ones at the bottom do take the greatest load.


If the logic is valid, then lateral force creates from 3 to 9 times the load on a spoke as does braking force. Now the geometry favors the spoke handling more lateral force - not sure what that number is.

My experience with my FF is that the max lateral G's I've ever seen on my data system was 1.8 compared to 1.3 in braking.

So, I stand to be educated.
Wishing you well.

One part of my analysis of the situation is looking at the break patterns on the spokes. The smooth crack-propagation areas that were visible in the photos are assymetrical only in the fore-aft direction. This indicated to me that the cracks started on one of the spokes' fore-aft wider faces and then propagated. Once a crack formed, the repeated side loading, combined with the severe stress concentration caused by the crack, rapidly accelerated its growth. In addition, tires are much stiffer in the circumferential direction than laterally, leading to much higher peak (impact) loads during braking than cornering.

The other part of my analysis is from practical experience: I have the "202" style Jongbloeds, which have spokes wider circumferentially and a bit narrower in-out. Photo below. A "202" is on the left, while the other style is on the right. I have used these for over 20 years (some of them the same centers for all that time) on an FC, which loads the centers harder than an FF. I have NEVER cracked one, even with repeated races at Indianapolis Raceway Park and Nelson Ledges, both quite rough. But, the worst roughness was not in braking areas.

So, to me, the difference in the spoke configuration is critical, with the cracked wheels experiencing much higher stresses fore-aft (acceleration/braking torque direction) than laterally, due to the spoke shape. Also all these spokes in the cracked wheels are radial, putting them all in bending during braking/acceleration. There is no "triangulation" of differing spoke angles (viewed from the side) to better handle the load. Most modern wheels with long spokes triangulate them somewhat in the side view, so some of the spoke loads are in tension and compression rather than pure bending.

[Swift17]

One pic of the actual center ....

Brief History -- Wheels were inspected (I guess not good enough) before the 40th last year - new tires installed

Then raced with those tires at Homestead SARRC in October & Sebring (Long) at the Thanksgiving "Turkey TROT"

New tires at Homestead dbl Nat'l -- then backup/testing at Sebring (Long) Dbl Nat'l

New tires at VIR Dbl Nat'l and testing - then used at Road Atlanta when "incident" occurred.

Jason says alot of bouncing at Sebring (Long) [very very bumpy] especially 17 and 1 but only some upon braking - VIR and Homestead smooth BUT very heavy braking espeecially off the banking at Homestead

[Dave D]

I used Alodine, a chromate conversion coating process, then a coat of clear.
Regards,
Dan Wise

Dan, could you please post a pic of a wheel finished this way?? I very interested in what shade the Alodine makes the wheels/ Can this be used for any alloy (mag and alu.) ??

Dave D.

[RussMcB]

Great thread. Good timing for me. I disassembled some Compomotives last night.

Quick question: When the centers are painted, do the mating surfaces need to be masked off?

[DaveW]

Added comment on distribution of cornering loads to post 31.

[DaveW]

Great thread. Good timing for me. I disassembled some Compomotives last night.

Quick question: When the centers are painted, do the mating surfaces need to be masked off?

I did not mask mine - but then, again, I used pretty thin paint and avoided spraying much on the mating surfaces.

[DaveW]

One pic of the actual center ....

Brief History -- Wheels were inspected (I guess not good enough) before the 40th last year - new tires installed

They may not have been cracked at that point - there is no way, now, to know.

Then raced with those tires at Homestead SARRC in October & Sebring (Long) at the Thanksgiving "Turkey TROT"

New tires at Homestead dbl Nat'l -- then backup/testing at Sebring (Long) Dbl Nat'l

New tires at VIR Dbl Nat'l and testing - then used at Road Atlanta when "incident" occurred.

Jason says alot of bouncing at Sebring (Long) [very very bumpy] especially 17 and 1 but only some upon braking - VIR and Homestead smooth BUT very heavy braking especially off the banking at Homestead

Braking is not the only fore-aft force generator - repeated high-torque impacts caused by rear tires losing/regaining contact with the track under power on the bumps, especially in the lower gears, may have been a factor.

[RussMcB]

I wonder, does the point on the track where the failure occured offer a clue?

For instance, if the cornering stresses were the cause, would the wheel most likely break in a corner? Or, if the failure was due to braking forces, wouldn't the wheel have failed under braking?

[Jonathan Hirst]

Hi Dave - Have you always run the outer rims halves on the front (outer) face of your centres? Many, not all, of the JB's I see are assembled with the rim halves together, behind the centre (such as the RH picture in your post).

You mentioned that you have NOT had failures in your experience with JB's - I just wondered about your thoughts on the inside/outside mounting and if you had always run them that way (FC vs FF application maybe?).

Regards,
Jonathan

Great thread.

[DaveW]

Hi Dave - Have you always run the rims halves on the front (outer) face of your centres? Most (not all) of the JB's I see are assembled with the rim halves behind the centre (such as the RH picture in your post).

The 6-spoke wheels (202's) I have are made to be assembled with the front rim in front and the rear rim behind the center section. I,e., there are two joints to be sealed. See attached photo.

You mentioned that you have NOT had failures in your experience with JB's - I just wondered about your thoughts on the inside/outside mounting and if you had always run them that way (FC vs FF application maybe?).

IMO, the mounting I use adds some extra rigidity to the assembly compared to having the rims both on the back side, but that would not be a major factor in center life.

Regards,
Jonathan

Great thread.

This mounting also removes 1/2" of rim width required, saving ~0.2 lb.