I recently replaced my Karate Monkey frame with a Marino custom steel frame. Marino is a small fabrication shop in Peru that makes just about anything you want for a LOT less than most foreign-made stock frames, and pennies on the dollar from what you'll pay a for a domestic (American) custom frame builder.
My steel hardtail frame involved sliding dropouts for singlespeed adjustability and a bent seat tube to allow for rear tire clearance. I paid about $700 total for the frame.
I wanted something a little more "modern" than my Karate Monkey, which means I mostly wanted a longer wheelbase from a longer front end. After a few emails back and forth over the course of a month with Elijah at Marino, we agreed upon a design, down to the details of where to put brake hose anchor spots and the paint.
I started the process in early November 2022, finalized the design in early December, and the frame was finished around Christmas time. The frame shipped from Lima just before the end of the year, languished in a Peruvian postal facility for three agonizing weeks, then suddenly appeared on my doorstep near the end of January.
Because my frame is a hardtail and not a full-suspension, and I apparently hit it at the right time of year, my who process was less than three months. I've read recent reports of people waiting for close to a year to get a frame from them, so be aware that many factors can affect total turnaround time.
I searched and searched for a frame that would suit me, but kept coming up empty. Frames on the market that came close but did not hit the mark it into three categories:
- overbiked: There are a ton of frames on the market are optimized around longer forks than I care to use. 130mm+ travel is just not interesting to me. What I consider to be super-long wheelbases are likewise unattractive. The Pipedream Sirius and Esker Japhy fall in this category. These are terrific bikes for someone, but I didn't want to risk finding out the hard way that I don't like them.
- boutique: there are some fantastic bikes out there that I'd love to own and ride, but my income doesn't justify the purchase. The Chumba Sendero and Neuhaus Hummingbird seem like amazing frames, but I can't responsibly shell out that amount of cash for a bike. Maybe some day I can.
My Design
I designed this bike with a few changes to the Karate Monkey:
- longer front-center and reach, which makes for a more stable ride and uses a shorter stem to achieve the same fit. I'm not sure I buy the idea that stem length really affects how a bike handles, but the stem has to be the right length for a given rider. I recently shoved a -1.5° Works Components headset in the ol Karate Monkey to length the wheelbase and enslacken the head tube angle and I liked it, so I designed the Marino to have a similar footprint.
- shorter chainstays. I love wheelies and manuals and the ability to easily, breezily loft my front tire over stuff. a few things make that possible: high bottom brackets (that is to say, minimal BB drop, not the same thing as height off the ground), short effective reach (how horizontally far the grips are relative to the BB), high effective stack (how vertically far the grips are from the BB), and short chainstays. All of these factors can combine to create a bike that is "nimble" but can come at the expense of a bike that is "stable". I poured over geometry charts and reviews of some bikes on the market that seem to mix these two factors well.
- 31.6mm seat tube that is short. I've been enjoying a 150mm travel dropper post, but I wanted a little more. I had Marino design the frame with a shorter seat tube with a wider seatpost. The trick was to locate the necessary bend in the seat tube at the right place that the short chainstays would not cause a large-volume tire to hit the seat tube. Because I new exactly where I wanted the seat to end up to achieve and effective top tube that fits me well, Marino was able to bend the tube just right for an "effective" and "actual" seat tube angle that works.
- optimized for a 120mm fork, or a 495mm rigid fork. If I made the BB too high or the head tube angle too slack, a fork of this length might not work very well.
Photos
This is why you came here, right?
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| One of the first drawings Elijah sent me for tweaking. |
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| I believe this is the final drawing I authorized to go to the welding stage. |
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| I received a few "in progress" photos of the frame in stages of production. Here is is just being born. |
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| Initial paint. I picked the color because I wanted something bright for once. |
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| Final image before shipping from Peru! |
The Bike Comes Together
Swapping parts from my Karate Monkey to the new Marino was a breeze. I chose no internal cable routing, other than a port in the seat tube for the dropper post. I had already ordered a OneUp 31.6 dropper after a black Friday sale and it was waiting for a frame.
The box included two pairs of dropout sliders with very nice hardware, two axles (beautifully machined), and a t-shirt. The frame came with a seatpost clamp as well.
I have no complaints about how the bike came together and how it fits and handles. It looks sharp, too.
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| Lots of room for a 29x2.4" tire with a 34t "non boost" spaced chainring and 420mm chainstays! This is about as tukt as it gets and probably a huge challenge for the builder. I should be able to use a larger volume tire if I want, but I might need to change the gear combo and pull the axle back a bit, which is fine. |
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| These sliders are nice, and the stainless bolts with a 6mm hex are stout. |
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| More tire/frame clearance. |
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| A large water bottle fits in the frame. |
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| One of my few complaints is these water bottle mounting point. They're welded in without much of a flat surface to support the cage or whatever accessory you might bolt on here. I might modify these for a better fit, but they seem to work fine. |
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| My only other problem is that this dropper post port routing is not very smooth. I might move that housing around for a better bend, but it seems to work fine. I also should have routed the dropper cable from the left side of the handlebar around the head tube to the right side of the down tube. The current routing has a tight bend from the handlebar that goes down the left side of the down tube. [edit: I found a practical and unattractive workaround for this.] |
Lastly, the weight. They say you can pick only two out of light, strong, and cheap. At 6 pounds, 11 ounces (3033 grams), this frame got the second and third is spades, but the first is not there. For reference, my medium Surly Karate Monkey is just over 6 pounds, and my previous Niner ROS9 was over 7 pounds. Nearly 7 pounds for a medium hardtail is hefty, but I suspect this frame is strong and I won't need to baby it. At less than 1/3 the cost of a similar domestic-made frame, I think it's a worthwhile tradeoff to get a bike that fits and handles the way I want it to.
My Personal Build
This is the only mountain bike I own, so over the years I've owned many iterations of, effectively, the same bike. I built this one up to be economical and durable.
- Tandell rigid carbon fiber fork, recently purchased used form a local rider
- Alternatively, I have a 120mm Marzocchi Bomber Z2, recently purchased
- SQLabs 30x low handlebar with 12° backsweep, purchased from SQLabs about five years ago. love this bar!
- Syncros 50mm stem
- Stan's Flow rin laced to a salvaged Bontrager front hub
- Industry Nine 1-1 Enduro rear wheel
- I change tires around a lot, but currently a Maxxis Rekon 2.6 front and Ardent 2.4 rear
- Raceface Cranks in 170mm. I might need to consider a shorter crankset for ground clearance
- Spank Spyke pedals I got in a trade
- 34t Blackspire ring and 21t Surly cog. I swap these around a bit, so I have a 30 and 32t rings, along with 18–21t Surly cogs to experiment
- OneUP 180mm dropper, purchased just for this bike during a OneUp Black Friday sale
- Ergon saddle that I recently won in a raffle
- TRP Slate brakes that I purchased used. They're really old and are likely to never die. I flushed them and replaced the fluid with Shimano red stuff.
- TOGSs on my grips with Ergon silicone. I like the TOGS. the grips twist a bit so I need a better way to glue them down.
