Check out my Instagram page for additional photos! @cam.r.blair When I was in my teens, I had a Norco Spitfire Turbo with a chrome steel frame and fork set and blue alloy components. I loved that bike, but was always envious of the ultra-BMX brand bikes that some of my friends had such as Redline, Haro, Diamond Back, Kuwahara, and Mongoose to name a few. The all-time ultimate was the P.K. Ripper. Anyone with one of these was a super cool, very awesome, totally radical dude. This past spring, almost 37 years later, I found a P.K. Ripper frame at a neighbour’s curb waiting for the recycling truck! It spoke to me and said, “Help me, rescue me, build me, please!” So I brought it home! I thought it would be a good project for showing my kids some bike mechanic skills (they are otherwise glued to Fortnite and Snapchat). But wait… this wasn’t a “real” P.K. Ripper frame… the dimensions seemed right, but something was off. It was made of steel and the original P.K. Ripper frames were aluminum! I poked around the internet and discovered there are a few “Thai (Thailand) P.K. Rippers” from the 1980’s. I decided to build the bike in the spirit of my 1980’s bike with light weight, aluminum and chromoly components on a steel frame. I also wanted the bike to celebrate SE Racing, despite that the frame is a knock-off (this practice was common in the 80s for just about anything—even Rolex watches). The build wasn’t easy! I’m not entirely sure the frame had ever succeeded as an operational bike in the first place. A bad weld on the seat tube made it nearly impossible to insert a seat post. I had to file the weld down inside the tube. There were welding defects that I ground off the frame in a few places. There were also a few small gouges deep into the metal that revealed themselves when I stripped the paint, requiring filler. When I went to purchase a headset, I discovered that the headtube was an irregular size. Luckily, I found one that would fit with the help of Sam Rucchetta at Sam’s BMX shop. However, the initial headset I purchased didn’t allow the gyro mechanism to pass freely so I had to source another and found one at Porkchop BMX. I wanted to use a new 1 ⅛” SE Racing stem with new old school (NOS) Landing Gear Forks so I purchased a Profile Designs stem converter from Amazon. When I tried it, I realized immediately that it wouldn’t fit in the Landing Gear Forks. It was a larger outside diameter than the inside diameter of the forks (22.2 mm vs. old school 21.1mm)! It was seemingly impossible to purchase the correct size of stem converter due to a Covid-19 related production problem in Asia, so I rigged up a “lathe” with my drill, and machined the stem converter down to the correct diameter to fit into the forks. I also modified the stem converter to accept a “Potts Mod” hollow stem bolt and used the 21.1 mm wedge that came with it. During assembly of the bike, the bottom bracket set was difficult to press into its tube, but I succeeded. The head set was a bit tricky to press into place, too, because the gyro mechanism tended to push one side up making it unlevel and requiring several attempts. The rear brake caliper would not reach the rim, which was puzzling. Even if I used a Dia Compe MX1000 caliper, which has a longer reach then the Nippon 883, it still may not have reached the rim. Moreover, the brake bridge for a P.K Ripper frame is flat, so the bolt and washers supplied with the brake don’t secure it in place properly. I ended up purchasing some flat stock aluminum and machined a brake extension. Lastly, to be able to install the stem pad with the Potts Mod, I purchased a ⅜” grommet kit and punched a hole through the pad to insert the grommet. This seems to work fine. Photos of the bike show the frame as almost black. It is actually a dark grey colour. If I were to do this build again, I would send the frame away for powder coating (and I might still do that). The paint finish looks nice, but is not nearly as durable as a shop-applied powder coat. This seemed out of budget for me when I began the project, but later discovered that there are places where the frame can be sent to have this done at a reasonable cost. Sam’s BMX (@samsbmxshop): - Tioga Style Tires (2.125 front and 1.75 rear), Blue - Mission Bottom Bracket Set, Black - Generic Seat Guts, Black - Dia Compe Tech 77 Levers, Dark Blue - Nippon 883 Front and Rear Calipers, Dark Blue Harvester Bikes (@harvesterbmx): - ACS Maindrive Freewheel 1/8" - 16t, Chrome - SE Racing Sticker Set, White - SE Racing Lockit Chain Tensioners, Blue - SE Racing 12 O’Clock Nylon Pedals, Black - SE BMX Life Grips, Blue - KMC 410 S1 Chain, Chrome - MacNeil Bikes Inc. rim bands - Odyssey Slic Kable and Housing, Black - Cinema Alloy Valve Caps, Blue Porkchop BMX (@porkchopbmx): - SE Racing 1/8" threadless alloy Knarler Stem, Blue - VP-H732 JIS Headset 1" Threaded 27.0 mm Crown Race, Black - OS Quill Stem Potts Mod Bolt M10 X 1.0 X 160mm, Black - Supercross NOS Seat Clamp 25.4mm (1"), Blue American Cycle (@americancycle): - SE Racing Landing Gear Forks 20” x 1” Threaded, Chrome - SE Racing Power Wing bars - 30” width / 9” rise - Redline Flight Crank Set, Chrome, 175 mm Planet BMX (@planetbmx): - SE Racing 20"x1.75" Sealed Bearing Wheelset - SE Racing Pad Set - Chrome w/ Black/Blue Logo - Neptune BMX 44 Tooth Chainring, Black - Chromoly laid-back Seat Post, Chrome - Yi Zhan OS Gyro Detangler (1” threaded forks) Amazon (@amazon): - Profile Design (1" to 1 1/8") Stem Adapter BMX B1KE STUFF / superscoobydoo7 / Ebay : - MCS seat, Black/Blue Riders Choice - Motorcycle Shop & Apparel: - Maxima Waterproof Grease Canadian Tire: - Kenda 20x1.75/2.125 Inner Tubes -Dupli-Colour Auto Paint, Graphite Grey Pearl -Dupli-Colour Acrylic Enamel Clear Coat, Gloss -Meguiar’s Gold Class Quik Wax -WD-40 Bike Chain Lubricant -3M Bondo Plastic Metal Home Depot: -Rust-oleum Self-Etching Primer - ⅛” x ¾” Aluminum Stock for Rear Brake Extension - Misc. Hardware for Rear Brake Extension Lowes: -1/2" Plastic Spacers for Rear Brake Mount
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February 2022
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