Rambler Inline 4 from Cook Customs

Rambler from Cook Customs

Rambler from Cook Customs

The AMD World Championship of custom bike building is something I usually check out for interesting builds, but last year, I totally missed it, maybe you did, too. So I was surprised when I was flipping the pages of the latest Motorcyclist magazine and saw the Rambler by Cook Customs. Dave Cook, from Milwaukee won it last year with a bike that could fool you if you glanced at it quickly. You might think someone took an old Indian 4 or some similar engine and built a rigid frame around it, but this engine is no Indian, it's from a mid 70s Honda CB550! The transmission is a BMW 4 speed R75 gear set in a Cook modified BMW R25 3 speed case with a Yamaha Virago shaft drive assembly. Dave built a girder front end and added perimeter brakes and a lot of other hand fabricated pieces, too.

The Honda 550 engine turned sideways looks very vintage with the hand fabricated exhaust and intake manifolds plus the exposed oil and fuel lines and everything else. Nice out of the box thinking. I like it.

Link: Cook Customs
Link AMD Championship

Rambler from Cook Customs - closeup of Honda 550

Rambler from Cook Customs - closeup of Honda 550

Rambler from Cook Customs - closeup of Honda 550

Rambler from Cook Customs - closeup of Honda 550


  1. John S says

    It’s very interesting as the transmission had to be cut off. The BMW transmission is connected to where the alternator formerly lived. It also looks like he’s using an updraft carb similar to an old Farmall tractor. (I wonder if the bike can run on kerosene?)

  2. mike says

    great looking bike, the brass fixtures and passages add a nice touch. love the mounts for the tank as well. really great unique ideas

  3. says

    Love it!
    Is that a stainless frame?
    I especially appreciate the marriage of components from seemingly incompatible machines.
    This genre (new disguised as antique) is fascinating, sort of a “steampunk” approach.
    What a conversation piece…this is a talented guy.

  4. Kirill says

    Very beautiful bike. I love the shaft-drive, inline 4 and the disk brakes. very very nice.

    btw, a question about “girder fork”. I thought girder fork was suppose to reduce the movement of the suspension while breaking. although this one won’t have a front break dive. still seems a weird geometry and what do u think of functionality? still it’s extravagant and cool.

    one of the nicest bike i’ve seen!

  5. GenWaylaid says

    I’ve always liked the look of the old longitudinal straight-four bikes, though I suspect they may not handle too well with their long wheelbases. Still, I’m surprised no major company is still making that layout when nearly every other arrangement of one, two, three, or four cylinders is being offered.

  6. todd says

    That seriously looks like that took a lot of talent to put together. I don’t quite care for the look but I can appreciate the work that went into it. It looks like using the front brake would cause the bike to lift rather than dive as the wheel tries to roll under the fork pivot.

    I wonder what it’s like to ride?


  7. AlwaysOnTwo says

    Well, that looks like real steel to me!

    And the concept is linear, i.e. it’s a retro looking custom that maintains that feel and flow throughout the entire execution despite the power plant and tranny/drive.

    This deserves applaud whether you’re into the style or not, and is a primo example of why others should not get the same accolades.

  8. sean says

    If the front fork works the way it seems to, with a single pivot, then the trail will vary with compression of the front suspension. So vehicle weight, centripetal load when turning, and wheel movement over bumps will all cause trail to vary. Ouch.

    Otherwise, it looks really sweet, tho. -SEan

  9. Rosscoe says

    While it’s not my kind of ride ~ I applaud the thinking and engineering that went into
    blending the engine ~ trans ~ shaft drive. Mr. Cook and his crew gave a lot of thought
    to creating a piece that flows from the front to the back. It gives the impression that
    it could almost be a restoration of some obscure old M/C instead of a ground up
    creation. Very well done indeed . . . . .

  10. marvin says

    OK even after the previous post I’m going to jump straight in with the negativity! To me the bike looks like it has sort of sagged down under its own weight over the years to give the low seat height. On the plus side the use of brass is gorgeous and the outstanding “yes I could do that ” feature for me is the petrol tank supports they are so simple and elegant if slightly extraneous. There is also something about no battery or a disguised battery that just appeals to me very rarely to my mind do side panels improve the loo of a bike.

  11. says

    Sean, it doesn’t matter, it’s art. There are lots of things that are less than optimal from a riding perspective, like the headlight height relative to the top of the wheel or the u-joint angle of the driveshaft, but this bike won’t care, it’s just awesome to look at and it knows it.

  12. GenWaylaid says


    Correct me if I’m wrong but the Rocket 3 has three cylinders, does it not? Still I suppose that’s close enough.

    What I like most about this custom is that (unlike the Rocket 3) it captures the flat, narrow look of the straight-fours from ninety years ago.

  13. Prestons says

    The Rocket 3 has 3 cylinders but BMW made longitudinal 3 and 4 cylinders inline just a few years ago. They did a nice job of keeping the length down.

    Didn’t the Honda 550 have the engine power coming off the center of the crank? This Rambler looks to take it off the end. This could make for some odd crank harmonics. Maybe with the detuning from one carb and the manifolded exhaust it doesn’t matter.

  14. says

    I think BMW has produced a series of inline 3’s and 4’s called the “K-bikes”.

    This is a very pretty “Art bike”. Some suspension and a headlight that would shine past the front tire and it might be an interesting bike to actually ride around on. Probably would sound really cool with no muffler too!!

    I’ve often thought of doing the same thing with an inline 6 Chevy engine. Wouldn’t make sense, but it would look cool!

    Out of box thinking? This is right out of the ballpark, Wow!

  15. Paulinator says

    This reminds me of a Danish bike I saw last fall – beautiful. It may have weird handling characteristics but that would probably only endear it to it’s rider (silk scarf and goggles required). This project highlights the designer/builder’s resourcefullness by turning an “available” Jap engine into a Henderson four.

  16. OMMAG says

    Outstanding creative juice went into that one!

    The fabrication quality bar just keeps getting set higher all the time it seems.

    One personal observation on the state of customs these days …… I’m beginning to feel like the builders are copping out by going to rigid rear ends. With all the effort that went into these bikes …. why would they not do something with the rear … like design and build a suspension? Yeah … JMO.

  17. nortley says

    As a retro this machine may have overshot its mark and taken on something of a pre-motorcycle era Victorian look, but I like it a lot. Is that a Kubota alternator sticking out behind the front cover under the exhaust?

  18. Ccknudsen says

    Paulinator: the Danish bike you saw, must have been the Nimbus. Engine looks like it, and it was a 750 ccm inline with the valve arms suited outside in open air. Looked great. This one will though have same problem as the Nimbus: COOLING. Cylinder nr. 3 gets less cooling than the others. So, if you ride it hard it blows up. History shows.

  19. says

    Really cool bike! I saw this bike for the first when I was looking for longitudinal straight-four bikes for inspiration on my own project.
    Nice job!!

  20. Lohmann says

    “So, if you ride it hard it blows up. History shows”

    Tell that to the two crazy norwegians who’s doing a 70.000km round the world trip on Nimbus motorcycles fitted with sidecars!

    No wonder they call it “The Dumb Way Round”. They’ve got a blog at: http://www.kccd.no/home_en.html
    It’s well worth a look, may even make you laugh :-)

  21. says

    Paulinator & Ccknudsen; The # 3 cylinder on a Nimbus does indeed get hotter than the others, which in the old days often resulted in a burned # 3 exhaust valve. Not a problem anymore, now that hardened valves and new lead-free-compatible cylinder heads are available. If kept withing the 50 mph cruise speed it (and its frame and brakes) was designed for, the cylinder head is usually good for 30K miles and the bottom end twice that. I have two of them, but when occasionally I want to go faster, I take the MZ stroker or the XS650.

  22. AlwaysOnTwo says


    I get that jaded feeling, too….about virtually EVERY bike regardless of configuration. Sometimes it’s just a matter of sensory overload, whether it’s the stretched and raked choppers or the one liter bikes with swing arms you could use for clotheslines. In this case I can’t see an articulated rear fitting in with the overall theme.

    @kirill & @sean

    Given a few more hours that I don’t have this week, it might be interesting to plug that front end into AutoDesk and do a few calcs on the rake and trail changes. I’ll wager, offhanded, that the real world ride would suffer only if pushed far enough to make the hardtail even more of a problem and the driveshaft angle started harmonic vibrations that would pound the bearings in the tranny case to silly-putty. Don’t think this design was meant for more than a slow strut to the local bistro to tease more plain janes, though! Good observation on your part, though.

  23. says

    I like the bike – pure naked eye coke… But I gotta wonder about the extreme angles for the driveshaft u-joints and the likely cooling constraints of the trailing three cylinders. Definitely bad for reliability and longevity.

  24. SteveD says

    Beautiful piece of machinery. Like many, I wonder what it’s like to ride. Maybe it’s not comfy for long rides, but it might be really fun on some short ones.

  25. 9nine8 says

    Beautiful work of art . . .notarize was ingenious modern-classic aesthetics, wonderful powerplant/drivetrain marriage, and so on.

  26. Thom says

    I live in Milwaukee, and I have seen Dave Cook and his bikes around town quite a bit. I have to say, this is the most unique bike he’s ever built, and I love the tie-in to the old Indian/Cleveland/Henderson fours of the thirties. And I do know, Dave rides ALL his bikes, and not just on short hops. Maybe they’re not ideal, but they work well enough. The Nimbus was produced from- I believe- the late forties until the sixties, there’s just a lot of them still around, since they were so durable. Also, I’m not sure if they are STILL in production, but there was a European company with rights to the Indian name making a longitudinal inline 4 back in the nineties, made out of VW cylinders on a Volvo bottom end, with a shaft-drive tranny not unlike a BMW boxer’s. (Maybe FROM a BMW boxer…) They were out of the same area in Europe as the Nimbus 750, but had much larger displacement. Kind of ugly, I thought, but the idea was good.

  27. PaulN says

    I can’t even get my head around the amount of work it must have taken to produce that machine. The imagination alone is worthy of praise. It’s like a gourmet meal for the other senses.


  28. says

    Thom; The Indian Four-ish bike with a Volvo engine block/internals, VW cylinders, custom cylinder head and a lot of H-D parts was a DIY project pioneered by Swedish custom car mag ‘Wheels’. (They had already made a DIY VW flat four engined 30s style tourer looking like an extra long 1936 Harley. they called it the ‘Folkshoj’ (go google it) and it could be slapped together by your average guy for about $6K.)

    The straight four eventually evolved into the small-scale production Wiking in Sweden, a venture which then later was taken over by indian enthusiast Alan Forbes in Scotland. It has all the visual charm of a water buffalo, though it’s still far from the hippo territory occupied by Boss Hoss.

    Incidentally, I visited a guy down in Czechia, who was building a series of 25 very faithful replices of an 1926 Indian Four, with only a few hidden improvements to the engines. The first one ran when I saw it 8 years ago. He was already in the business of making Indian repro parts.

  29. John S says

    As far as cooling goes, that’s an especially durable motor. I had a 1974. At 30,000 miles the compression was a bit low so I lapped the valves. I then proceded to put another 13,000 miles on that motor — in 6 weeks. (Rode it from Boston to San Diego and back, with passenger.) While the 550 wouldn’t do more than 20 mph climbing Independence Pass in Colorado, the Mojave desert didn’t phase it. And concerns about reliability never entered my mind. (It’s nice to be 20 years old and stupid.) I later bought a 1975 model and rode that one 15 years. My brother still has it.

  30. B*A*M*F says

    Yes it’s an art bike, but it is quite beautiful. I would venture to guess that it can actually be ridden too. Perhaps only on special occasions, but imagine about how special of an occasion it would be to roll up on a bike gathering with a machine that looks like that.

  31. Seymour says

    I love this bike, especially the engine. I wish we could have an inline 4 motorcycle available to us, the consumer, at a reasonable price.

  32. Paulinator says

    Nimbus! That’s the name I couldn’t recall. Thx.

    Interesting notes about cooling #3 cylinder/head. Back in my VW days I learned that the factory retarded #3 lobe on the distributer because of similar issues. The cylinder was farthest from the cooling fan and tucked in behind the oil cooler. The late spark took some of the load (and horsepower) off that cylinder.