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tjwilson

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Jumping in a little late again... I purchased this a couple years ago for the seat pan (I needed a riding saddle for my '69 Fastback). I don't remember exactly what I paid. Wasn't much and was a good deal for the seat. Part of the delay in getting started is because I couldn't decide what I wanted to do. Initially I'd planned a complete overhaul - gears, disc brakes, new paint, etc. The more I looked at it though the better it looked as is. Settled on a thorough cleaning and some minor modifications to make it ridable.

01_driveSide.jpg

02_nondriveSide.jpg


Not real sure of the date or manufacturer. I believe it's an AMF? I'm also guessing it's a 78 or 79. The BMA/6 label started to be used in the early 70s from what I was able to find. Side reflectors started to be required in the late 70s. Assuming the wheels and reflectors are original to the bike (big assumption) and that the reflectors are date coded to the reflector manufacture date (another assumption) that puts it at a 79.

04_bma6Label.jpg


05_refectorDate.jpg


Wasn't able to locate any reference based on the serial number.

03_serialNumber.jpg


Here's a roundup of additional details on what I'm starting with. Rear bridge was welded on crooked but there is a lot of room there, and at the chain-guard for a wider tire.

06_detailCrookedBridge.jpg


07_paintPeel.jpg


08_chainGuard.jpg


09_headbadgeSticker.jpg
 

tjwilson

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Rims cleaned and new tires mounted. Original tires were Trelleborg, 20x1.75 slick rear and 20x1.75 front. New tires are Odyssey/Hawk 20x2.40 rear and Kenda Kwest 20x1.50 front.

01_oldTires.jpg


02_newTires.jpg


Part swaps to make it more ridable include taller bars (14" verses original 10.5" rise), longer seat stem (14.5" verses 12"), and longer cranks (6.5" verses original 4.5" arm).

03_bars.jpg


04_seatStems.jpg


05_cranks.jpg
 

tjwilson

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Pulled everything apart. What didn't get a good scrubbing and polish went into a citric acid bath. About half a teaspoon of citric acid (powder used for canning tomatoes in place of lemon juice) per cup of water. The rims received the same citric acid bath treatment. Works really well at removing rust. The chain probably illustrates that best. You do have to be careful that it doesn't strip other finishes (like zinc coatings) off if you want to keep them.

Before
01_piecesPartsPreCitricAcid.jpg


After
02_piecesPartsPostCitricAcid.jpg


Frame cleaned and polished
03_framePolishedDriveSide.jpg


04_framePolishedNonDriveSide.jpg
 
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Pulled everything apart. What didn't get a good scrubbing and polish went into a citric acid bath. About half a teaspoon of citric acid (powder used for canning tomatoes in place of lemon juice) per cup of water. The rims received the same citric acid bath treatment. Works really well at removing rust. The chain probably illustrates that best. You do have to be careful that it doesn't strip other finishes (like zinc coatings) off if you want to keep them.

Before
View attachment 143603

After
View attachment 143604

Frame cleaned and polished
The parts were meticulously replaced in near identical positions relative to the background.
I wonder what Gil Grissom would say about that...
 

tjwilson

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The parts were meticulously replaced in near identical positions relative to the background.
I wonder what Gil Grissom would say about that...

Been a while since I watched. Didn't most of the suspects have some type of obsessive behavior? I might be in trouble...
 

tjwilson

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Started putting things back together. I'm really happy with the tire selection.

01_assembly01.jpg


Amazing the amount of space that's available for tire clearance without modification on this frame.

02_tireClearance01.jpg


03_tireClearance02.jpg


I was a little concerned about crank clearance when I swapped out for the longer crank arms. Got lucky again, plenty of room.

04_crankLongArms.jpg


05_crankStandClearance.jpg


06_crankGuardClearance.jpg


07_guardPedalSprocketDetail.jpg


Tried to keep the contrast between the different finishes as best as I could while cleaning everything up.

08_zincChromeContrast.jpg


Just waiting on the seat and sissy bar.

09_assembly02.jpg
 
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Started putting things back together. I'm really happy with the tire selection.

View attachment 143804

Amazing the amount of space that's available for tire clearance without modification on this frame.

View attachment 143805

View attachment 143806

I was a little concerned about crank clearance when I swapped out for the longer crank arms. Got lucky again, plenty of room.

View attachment 143807

View attachment 143808

View attachment 143809

View attachment 143810

Tried to keep the contrast between the different finishes as best as I could while cleaning everything up.

View attachment 143811

Just waiting on the seat and sissy bar.

View attachment 143812
Looking good TJ! You were right on the money with the tire selection! All those small changes went a long way!
 

tjwilson

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Here's a couple close-ups of the sissy bar before and after the citric acid bath.

01_loopPreCitricAcid.jpg


02_loopPostCitricAcid.jpg


03_endPreCitricAcid.jpg


04_endPostCitricAcid.jpg


What's the saying... "when the only tool you have is a hammer everything looks like a nail"? Yeah, rather than trying to find a taller sissy bar I pulled out the welder and spliced 4 inches into the one I had. Didn't spend all the time required to try and make the connections disappear but they're close enough.

05_4InchSleeve.jpg


06_welded.jpg


07_weldPreCleanup.jpg


08_weldPostCleanup.jpg


09_lengthenedSissybarComplete.jpg
 
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25.5'' hole-to-hole is a good length for adults. What do you apply to prevent future rust?

Almost seamless
 

tjwilson

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25.5'' hole-to-hole is a good length for adults. What do you apply to prevent future rust?

Almost seamless

Hole-to-hole on the sissy bar ended up at 23.25”. Arrived at that by measuring from the crank center to the middle of where I wanted the seat. Somewhere between 26.5” and 27.5” has proven to be the most comfortable for me.

I’ve had luck with just a good coat of wax to prevent rust returning. Used the same cleaning method on the Fastback the original seat from this bike ended up on as a riding saddle. That was a couple years ago and the Fastback looks the same. Although to be fair it is stored inside.
 
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