Refinishing a crank arm
07-30-22 | 07:22 PM
#1
Thread Starter
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From: NW Ohio
Bikes: 1983 Univega Super Strada, 1986 Panasonic DX5000, 1984 Fuji Team 85 Univega Gran Turismo, 1984 Lotus Unique, 1987 Centurion Expert, 1987 Centurion Ironman Master,
Refinishing a crank arm
Recently picked up a 1989 Centurion Ironman Expert. I believe the
crank arm is a SuntourGPX.. Both crank arms have a worn matte finish
in the same spot. I'm wondering if I'd better off just trying to strip the
finish completely off to the bare metal instead of trying to match the matte finish.
crank arm is a SuntourGPX.. Both crank arms have a worn matte finish
in the same spot. I'm wondering if I'd better off just trying to strip the
finish completely off to the bare metal instead of trying to match the matte finish.
07-30-22 | 08:59 PM
#2
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From: Western MI
Looks like a painted or powder coated silver finish. Really no way to touch it up with anything durable. You could have the whole crank powder coated.
I’m assuming high-polish is not the right look in this case. Twer me, I’d strip and wet sand to a duller polish. Then I’d probably try steel wool to make it look more unpolished and more like matte silver.
I’m assuming high-polish is not the right look in this case. Twer me, I’d strip and wet sand to a duller polish. Then I’d probably try steel wool to make it look more unpolished and more like matte silver.
07-31-22 | 11:39 AM
#4
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I have a '89 Master and I recall when looking the '89 Expert they dropped the 105 and went to Suntour's new GPX group, crank, FD and RD, etc. If an '89 yours is white as shown but with beautiful (to me) smoked blue on the fork, HS area and the stays which I would rather have had than the smoked grey I got. The above advice is spot on for powder coating.
07-31-22 | 11:48 AM
#5
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From: Madison, WI USA
I have a '89 Master and I recall when looking the '89 Expert they dropped the 105 and went to Suntour's new GPX group, crank, FD and RD, etc. If an '89 yours is white as shown but with beautiful (to me) smoked blue on the fork, HS area and the stays which I would rather have had than the smoked grey I got. The above advice is spot on for powder coating.
07-31-22 | 12:44 PM
#6
Thrifty Bill
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From: Mans of NC & SW UT Desert
Bikes: 86 Katakura Silk, 87 Prologue X2, 88 Cimarron LE, 1975 Sekai 4000 Professional, 73 Paramount, plus more
When I get cranks with wear like that, I tend to strip the finish. At that point, you will have to polish it, repeatedly.
I am becoming a bigger fan of patina. That wear has no impact on functionality.
I am becoming a bigger fan of patina. That wear has no impact on functionality.
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Please don't confuse ebay "asking" prices with "selling" prices. Many sellers never get their ask price. some are far from it. Value is determined once an item actually SELLS. Its easy enough to check SOLD prices.
08-01-22 | 08:58 AM
#8
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Bikes: You had me at rusty and Italian!!
08-01-22 | 04:29 PM
#9
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From: PDX
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Full on coating, a PITA, warrants some kind of scorched earth stripping, stripper, drain cleaner, etc. Fast, effective, nasty.
Anodized can often be sanded some with a sanding sponge that will conform to the shape better, and then scrubbed with Scotchbrite and maybe rust/corrosion/cleaner.
I can usually get an acceptable happy medium. The trick is to stop before you make a too nice spot and have to keep going.
Elbow grease is quickly becoming harder to come by.
Anodized can often be sanded some with a sanding sponge that will conform to the shape better, and then scrubbed with Scotchbrite and maybe rust/corrosion/cleaner.
I can usually get an acceptable happy medium. The trick is to stop before you make a too nice spot and have to keep going.
Elbow grease is quickly becoming harder to come by.
