Honda XR600 9 Cylinder Radial Engine Progress Continues

XR600 9 cylinder radial gears

XR600 9 cylinder radial gears

A thing of beauty is a joy to behold and this is certainly mechanical beauty. Some new photos just arrived from down under, courtesy of Ian Drysdale, who is working on this marvelous 9 cylinder radial engine with Russell Sutton, using Honda XR600 top ends.

We've written about this project twice before which began back in 2008 and the in-progress photos show it's well along towards the initial start up, I hope they're planning on lots of video. The engine will be used in an airboat.

Just check out the workmanship, very nice. Great project!

Previous coverage here:
XR600 radial engine
XR600 radial engine update

More photos below:

XR600 9 cylinder radial gears close up

XR600 9 cylinder radial gears close up

XR600 9 cylinder radial master link and rods

XR600 9 cylinder radial master link and rods

XR600 9 cylinder radial exhaust

XR600 9 cylinder radial exhaust


  1. Paulinator says

    This engine will probably have similar performance to the Russian M14-P radial on pump gas but I wonder how well it’ll run on straight Vodka?

  2. joe says

    Fantastic ! This guy realy knows how to come up with sound engine designs using proven,off the shelf components without trying to reinvent the wheel .Well done again Ian.

  3. MikeC says

    Absolutely beautiful. A work of art, just like the Drysdale V8.

    I wonder how he is scavenging the head oil? Also, can I assume the gears are for cam chain drive? At first I thought the gears were from separate cranks to a master output, but then saw the master/slave rod set-up. Looks very cool. Can’t wait to hear it go. Good Luck.

  4. says

    Very nice. That’s going to be a LOT of timing chains whirling around when this is running (along with the inherent harmonics/friction/rotating mass). Has anyone thought of maybe incorporating the cam into a perimeter affair- sort of like having the lobes on the outer edge of a light weight ring (resembling an automatic tranny flex plate with lobes where the gear is). It could even be Desmo like the Ducati’s. The rotary mass would be reduced greatly. Just a thought, clueless as it may be.

  5. nortley says

    This sort of aero-moto artwork could go in either direction. How about a Pratt & Whitney v-twin for two wheels?

  6. Scott Helmer says

    Wow, to think I hadn’t even read the previous articles on this engine, and yet not even an entire week has passed since I thought to myself that I wanted to build a 6 row, 5 pointed star formation radial engine using RB26 heads! However, since I’ve no idea how one would go about creating either a water cooled radial or modifying an RB26 head to work well in an air-cooled environment, I shall look upon the above pictures and drool, thinking fondly of the engine that will probably never be (I wouldn’t know what to put it in anyway, other than a crazy arse boat or a humongous hot rod xD). Unless of course the person behind the XR600 radial wants to contact me and work on such an idea :P.

  7. Russell Sutton says

    Todd. Yes 72 rocker arms and I thought you may be interested to know that there are around 1350 individual parts to assemble the top ends.
    MikeC. Take a look at the top photo, The No 1 cyl has the oil filter in front of it. Notice the small hose running over the No2 header pipe above and again between No2 and No3 cylinder. These hoses drain areas in the valve covers that would pool. The lower Cyl’s will have fittings screwed into the valve cover caps for more hosing to drain oil to a collector tank.
    Thanks for all the comments .It’s great to have your interest in the project.

  8. Mike says

    Hey Russell, I was just surfing the net and came across your project. I have a Honda XR and when I saw this radial engine was composed of 9 XR600 top-ends it completly caught my attention. This is quite the job you have done here, reading all the details I thought it was pretty cool. The Honda RFVC engines have a sound all their own, and as many others have commented I sure would love to hear this thing started!
    Awsome job, keep it up!

  9. Terry H says

    That is a great engine project! I linked to your site from my Mach3 email messages.

    I was lead engine mechanic on a Douglas C124 during Vietnam. These aircraft were fitted with four Pratt & Whitney R-4360 engines. So I am very enamored with radials and always will be.