The Kneeslider

Doers Builders and Positive People

Honda CB-1.5 – Big Changes Hiding in Plain Sight

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Alex Zemlin's Honda CB-1.5 - an engine swap and a lot of other work done very well
Alex Zemlin's Honda CB-1.5 - an engine swap and a lot of other work done very well

Many of us have had the experience of seeing a motorcycle, and noticing nothing out of the ordinary, we walk right by, but then, something makes us turn around and look again. With this bike, however, what builder Alex Zemlin calls his Honda CB-1.5, the craftsmanship is so subtle, the quality of the modifications so high, most of us wouldn't turn around and that's a shame, because it is a beautiful piece of work.

Alex sent me some photos he thought we would appreciate. This 1989 Honda CB-1 was originally powered by a 400cc inline four. Nice bike, lots of fun, but Alex thought it would be even nicer and more fun if he put some extra power in the light and compact frame. The engine from a '96 CBR600F3 seemed like just the ticket, and that's what you see here, hence the CB-1.5 designation.

Alex Zemlin's Honda CB-1.5 - a close up look at the engine illustrating how well it fits and the caliber of the work
Alex Zemlin's Honda CB-1.5 - a close up look at the engine illustrating how well it fits together and the very high caliber of Alex's work

He modified the frame to make room for the engine, the carbs fit nicely between the frame rails and the airbox fits perfectly under the tank. He modified the wiring harness so he could use the throttle position sensor for the F3 carbs.

Up front are 2007 CBR600RR forks with radial calipers. Gauges come from the same place. Wheels are F3 front and rear. Rear shock courtesy of a CBR900RR with an ST1300 spring.

He installed full race stainless head pipes with a Ducati 1098 muffler.

The end result is a 406 pound bike with 94 horsepower to the rear wheel, about twice what you would get from a stock CB-1.

This is the kind of work I can really appreciate, big changes and it looks completely stock and just the thing to surprise the heck out of some 600cc sport bike rider who can't seem to shake the little CB-1. Nice work, Alex! Very nice.

Alex Zemlin's Honda CB-1.5
Alex Zemlin's Honda CB-1.5

Comments

  1. That is awesome! It reminds me of those Kawasaki engine swaps people were doing in the 80s…KZ900 engines in a Z550 frame, I think is what they were doing.

  2. Great engine. That is what powered the 600 Hornet. I have a 04 model. A great bike.
    Honest, bulletproof engine.
    Wonder what the handlimg is like with the 400 frame.Nice new brakes were always a help.

  4. I always loved the CB1 from day 1 – though I loved the FZR400 more. It was fairly common to swap the 600 motor into the FZR because the little 400 was a higher spec chassis than the 600. That’s not really the case here with the CB1. It would have been loads easier to put a round headlight on a 600F3. If he wants to impress the 600 sport bike guys, he should just improve his skills; a CB1 with a good rider can easily keep up, or outrun, a typical rider on a 600. I’ll take a nice FZR400 and work on my skills instead.

    Quality work otherwise.

    -todd

  5. As a recently former Hawk GT owner… I understand this bike, too.

    Honda tried to be interesting, nobody bought them and only bought CBR600F1 Hurricanes, and the CB1, GB500, and Hawk GT died… and have never come back. Now SuperHawk has joined that list, and likely the 599 and 919 “Hornet” models.

    This is a fantastic bike. The mods are extremely well done.

    A CBRF3 without fairings is not this clean and gorgeous. Maybe a 599 with some tasteful modifications could look this clean, without a frame that was designed to be hidden behind tupperware cladding.

    The only thing better, would be a Hawk GT/VFR single-sided swing arm, blacked out like the rest of the frame.

    I would like a modest half fairing and a little bit of a chin-fairing at the bottom of the engine… like a Honda VF500 Interceptor pieces, painted to match the grabber-style blue of the stock tank and tail… but I understand that this, like the Hawk GT, were built without fairings… and they tend to stay that way.

  6. You can take the jeweler out of the jewelry shope but you can’t take the motorcyclist out of the garage! Nice work! (as always)

  9. Thanks for the kind words from everybody, even todd.
    A little bit of background on the bike that I didn’t get chance to convey to Paul.
    The bike was conceived and started by a well known roadracing crewchief who gave me the chance to build and finish it. It was runner within six months after receiving it as a roller
    with an engine hanging on two mounts, the rest was up to me. Two years later it became what you see here.
    To answer to todd, yes I could have stuck a round headlight on an F3,
    That would have given me a streetfighter, which I didn’t want.
    What I wanted though was a factory level finished CB-1 with the power of an F3 and updated brakes and suspension.

    • Alex, do you have a build thread for this bike anywhere? I’m curious about how difficult it was to get the 600 in there.

      • Phoebe, sorry I don’t have a build thread. I’m to impatient to stop and take pictures while I’m at it.
        Unless you can compare a stock one to mine side by side you’d be hardpressed to see all the hurdles that had to be overcome in making this work.
        If I had to build another one, I’d start with one of the original ’87 Hurricane engines. The crankcases look to be very similar and might actually make it a bolt on proposition. Not as much horsepower but still more than the CB-1.
        The only stock motor mount left is the bottom rear, everything else is new.
        The F3 airbox doesn’t fit under the tank, the CB-1 airbox doen’t fit the F3 carbs, the seat has to be moved as do the coils. The list goes on.
        If you really want to go there, start with older Hurricane engine. It should be easier.
        You’ll find more pictures right here: http://www.advrider.com/forums/showthread.php?t=590493

  10. Wow, that’s so clean. I would love to have a bike like this. The CB-1 fits me well, since I’m small, but it would be great to have the power of the 600. Well done!

  11. It’s nice to see well planned and executed modifications that result in a bike that is tastefully balanced. All the changes are improvements that don’t sacrifice civility. A far cry from the heat-wrapped pipes, Firestone tires, and upholstered brick seats of the typical bobber/cafe/custom. A true Gentleman’s Express.

  12. Honda should be building this. They used to build something like it, the 600 Hornet but it was discontinued.

    • The 600 Hornet is still being made (in Italy) and is a big seller everywhere in the world where it is sold. But not in America.
      There are about three different varients of the Hornet formula from a detuned commuter (zzzzzz) to one with the CBR fairing but not the CBR power.