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1960s Simplex Challenger Mark IV Dual-Engine

The 1960s and 70s had to have been the golden era for motorsports, at least simple ones like early snowmobiles, minibikes, and a kid’s dream ride like this 1960s Simplex Challenger Mark IV 580 dual-engine go-kart. This twin-engine project kart is listed here on eBay in Bucyrus, Ohio and the seller has an opening bid price of $3,999.99 listed.

Beginning in 1935, Simplex Manufacturing Corporation out of New Orleans, Louisiana made some fantastic small-engine creations for having fun and even manufactured small motorcycles for commuters and recreational riders named the Simplex Servi-Cycle. The Servi-Cycle went away in 1960 but the company continued to make minibikes and go-karts, such as the Challenger, until 1975 when production shut down.

This looks like an incredibly straightforward restoration project. Just disassemble everything, sand and/or sandblast and paint it, badda-bing, and you’re done. What could go wrong? Says the guy with a half-dozen restorations hanging in limbo as I’m always looking for the next one rather than finishing anything. There should be a Simplex logo rubber floor mat and that may be hard to find, and I’m not sure what else may be missing, but it looks pretty complete overall. Dual brakes pedals are a nice feature, and the display stand is not included, just for the record.

Life sure seemed simpler back then, but then again, I was a kid so what did I know? Simplex made the Challenger in four versions in this era, the 2.5-hp Clinton engine-powered Mark III A490 Single and Mark IV A490 Dual with two 2.5-hp Clinton engines. Then came the Mark III 580 Single with a single 5-hp West Bend engine, and the Mark IV 580 Dual with dual West Bend 5-hp engines. This is the one you want, hence the seller’s seemingly high beginning bid price. They can easily sell for double that beginning bid price in restored condition.

Here are the very cool twin West Bend 5-hp engines giving 10 horsepower total. The seller says that this kart has sat for 16+ years and will need a full restoration, including taking care of some rust in the gas tank and all of the usual procedures. Have any of you owned a Simplex go-kart? Bonus for one with two engines!

Comments

  1. Howie

    Blasting around in a parking lot, it would be very easy for those carbs to catch a small rock with no screens or filters on them. Cool item but out dated for that price.

    Like 2
    • Euromoto Member

      “Cool item but out dated for that price.” Could be said about 90% of what shows up on Barn Finds.

      Like 31
      • Gary

        They are always”A cool item but outdated” if they are worth having.

        Like 9
  2. Jay E. Member

    Not sure about the dual brake pedals as I think the right one is the gas pedal.
    Must be a lot of fun to drive, even better with twin pipes. If I owned it, it would be out on the local track.

    Like 11
    • Scotty Gilbertson Staff

      I think you’re right, Jay, my mistake. I meant “Dual brakes” (as seen in an old brochure) but typed dual brake pedals for some odd reason, ugh. Thanks for catching that.

      Like 9
  3. HoA Howard A Member

    Okay then, on a previous go-kart post, that the comments went missing( stupid sunspots), I pretty much went on a bender that many may not have seen. In a condensed form, 1st, a huge thanks to SG, and for the staff to post his wacky submissions( what’s wacky?) you can just tell the kind of childhood this guy had. It paralleled most here I bet.
    As a kid, go-karts were the epitome of recreation, where space permitted. Go-kart tracks sprung up all over creation, and I believe, the Wis. Dells still boasts the most. For many, we weren’t old enough for a car, and by golly, this was close enough. Many future driving skills in a car, were learned from go-karts. Lucky was the person that had their OWN go-kart, which me and my brother did. Somehow we got a hold of a late 50s Royal Norseman, that was unbelievably featured here a while back( you still think I’m nuts about BFs in my head?) https://barnfinds.com/vintage-go-kart-1959-royal-norseman/
    We had a long paved side driveway and drove our neighbors nuts. It was a far cry from this kart, but it gave us plenty of thrills. It had 3 hp Briggs that was a glorified garden tiller motor, and belt drive, no brakes to speak of, just a bar that rubbed one back tire( went through a lot of PF Flyers, though), and for many like me, it was the 1st attempt at taking a motor apart. Putting it back together was the hard part. Naturally, in true American fashion, more is better, and 2 motors seemed to be the answer. I believe these are the same motors that are on Scottys Rokon, and a million other uses. If, and a big IF, you did happen to get both motors running right, these could be outright dangerously fun. 60 mph + easy, and with little or no brakes or suspension, little or no safety roll bar, heck, we never even wore a helmet,,kamikaze city.
    Still, fun is what you make it, and Americans were pros at it. I believe twin engine karts went away in favor of one BIG one, but even with one motor, this has fun all over it. I all but guarantee, a go-kart will put a smile on every kids face, it did 50 years ago. Yeah, even “punks” too,,,sorry, about that( ’56 Chevy), punks want to have fun too. Too bad it’ll cost them a kidney today,,,was my point.
    And, checking for sunspots( @4am?) and submit,,,,,,,,,,,,,,,

    Like 3
    • Terrry

      I vaguely remember a neighbor who had a twin-engined go-kart that was powered by two McCulloch chain saw motors. What I remember most was him trying to get both of the engines to run at the same time(they were a bear to start) but when they ran that thing was fast!

      Like 0
  4. Bamapoppy

    Had a scary moment one Saturday morning when I caught a red triangle flag with my peripheral vision moving in an apartment parking lot. In a matter of seconds that flag and the go-kart it was attached to drove onto the road I was on. Dad must have known the kid only cared about the fun he was having driving around!

    Like 5
  5. Rw

    Will probably sell between 6to8k, check current pricing on vintage go karts.

    Like 6
  6. Phipps

    Gotta love the nuts padding

    Like 12
  7. Dan Baker

    I raced one of these in 1962 in N.West Ohio when I was 13. I have never seen another until this photo. Mine had white upholstery. Loved it. I believe these shown are West Bend 580’s. Also made a 700cc. I started with the 700 West Bend then a Power Products (Tecumseh) then finally a Muculloh, which was the “hot” engine. We did not use centrifugal clutches as you lost a lot of power. Direct drive, 9 tooth on the engine, 72, on the “live” axle. It would scream but would make lots of small bits of scrap if you kept it wound up on a long straightaway. We ran dirt tracks with knobby tires. With to clutch, some one had to push you to get started and while lining up to await a green flag, you had to ride the brakes to keep engine speed up. To start it yourself, you picked up the rear and ran along beside that kart, dropping it to get the wheels turning. Embarrassing if it started before you jumped in. Some were fuel injected and ran alcohol. Following those karts would give you a cheap high! I had a 1928 Model A Ford. I was then 16. It had a split rear bumper. I wedged a short 2×4 into each bumper and sat the kart on top of the boards. Lashed it to the spare tire and off I went to the races. I have a neat photo of me at age 13, holding a checkered flag. Other engine choices were Clinton (off an old self propelled reel mower) and Homelites off a chain saw. Nothing ran like the Mac’s. The Simplex had internal expanding brakes on each rear wheel. I paid $100 for mine, used, with no engine. What a wonderful childhood. From karts I moved to late model stock cars on 3/8 mile dirt tracks. I had a ’57 Chevy. Dime a dozen then, in ’65. Viet Nam was in full swing and I got drafted. Sold the 301 out of the Chevy, bought my girl an engagement ring and went off to work for my Uncle. (Sam). That ended my racing days.

    Like 27
    • Chunk

      I would buy and read your autobiography.

      Like 18
  8. Dan Baker

    Almost forgot. West Bend used a fiber barrel type air cleaner. We removed them and fastened a piece of old nylons over the intake. Worked great.

    Like 5
  9. bull

    I had this cart in 1969. With our circle driveway and the street out front I was Mario Andretti racing around my own personal oval race track.

    Neighbors were not to thrilled as the cart was LOUD with both Westbend engines roaring!

    Like 7
  10. bull

    I had this cart in 1969. With our circle driveway and the street out front I was Mario Andretti racing around my own personal oval race track.

    Neighbors were not to thrilled as the cart was LOUD with both Westbend engines roaring!

    Like 5
  11. Dan Baker

    Although it was “illegal” at most tracks, some foolish racers would reach back to “lean” the carbs. Very easy to lose a finger in the chain.

    Like 5
    • Melton Mooney

      I went to a 500 lap enduro go kart race back in the early 70s. The track was set up behind and beside a shopping mall. Lots of the drivers were reaching around and fiddling with their motors as they hit the main straightaway. Now I finally know what they were doing.
      Thanks, one less thing to wonder about.

      Like 1
      • Dan Baker

        We never ran chain guards and on the two cycle engines, you could reach back and lean the carbs but man, it was so close to the drive chain !

        Like 1
  12. Bob P

    I had a couple of Margay chassis’ (a sprint and an enduro) powered by my beloved Westbend 820. The enduro, in multi-carb configuration, had a top speed of 115 at Riverside International Raceway (not with ME driving it!), but my sprint maxed out around “too fast for the bank parking lot”. I never had a Simplex, but I remember them. If people will pay $3000 for a Taco 22 mini bike, this will sell.

    Like 0
  13. Chuck W.

    I had dual West Bend 580’s on this exact kart. Bought it used in 1962 for $200.00. Dad loaned me the cash. I was 14. My second kart.
    I drove it mostly on the dirt between the rows of harvested sweet corn.
    I broke the frame from the rough turf. I drove 1” pipe up the 4 frame pipe’s to reinforce the frame.(I did not have a welder) Later I would drive on the asphalt roads in the country. Drove into a subdivision with one entrance/exit. Engine screaming. Residents screaming, waving their fists in the air. Some man came out into the street screaming at me. Ranting for at least a minute. I couldn’t understand a word he said over the roar of the two-cycle engines. I finally drove off in amazement of my venture. I was 2 miles from home. Could I make it home? I did——coasting down the hill to the driveway. It was great!

    Like 3
  14. Dan Baker

    Thanks so much Scotty for posting the photo of the Simplex. I so much enjoyed reliving the memories of the days when karting was so popular. Numerous fine tracks, kart clubs, a National Karting Magazine. We had a beautiful dirt track wit a road course. Lights for night racing, a concession stand, traffic lights on each turn and a very nice flagmans stand. This was all in our little town of 2100 people. Close y in Fremont, OH. There was a similar configuration but it is asphalt. Karting was very popular here. Numerous kart shops also. I learned to race on a kart. Also learned sportsmanship and winning wasn’t everything. It was ok to loose now and then. I worked weekends on a local farm doing chores, etc. to pay for my love of racing. Thanks again for the memories. I’m almost 77 now but wouldn’t hesitate to take a lap or two!! Lol!

    Like 6
    • Scott Hart

      Karting is still going at G&J kartway in Camden Ohio. Went to a Vintage race this past summer

      Like 1
  15. Bad brad

    Sissy cart!! I grew up formally with an all race family. Draggers, stock cars, drag boats, motoctoss. Great child hood!@
    My go cart was powered by 2 mac 10’s chain saw motors in mid sixties. Including expansion chambers. These carts would absolutely endless burn of, couldn’t keep tires on em.
    Extremely dangerous cause they did 100mph, and regular cars and trucks couldn’t see ya coming. 20hp of screaming 2 stroke power felt like 200hp.
    So not impressed at all with whimpy hp, or 4000. Grand price. For 2000 grand i could still build same cart i had in 60’s.

    Like 1
  16. Timothy Vose

    I had something very similar to this. But I don’t think it cost that much. You can buy a new one for about the same price.

    Like 1
  17. Mark Ruggiero Member

    I don’t think the opening bid is out of line. Check BAT for kart auctions, some go for serious money.

    Like 5
  18. Marco

    Oh man does this bring back memories. I had forgotten the Kart we had as kids was a Simplex Challenger with the single Clinton engine. Drove that thing around our circle driveway for endless hours. Had a crash helmet and googles and though I was A.J. Foyt. Neighbors probably hated me since it was a (previously) quiet street! After I outgrew it some city kids stole it and drove it down the middle of some nearby railroad tracks. Cops got it back but they had trashed it and the frame was broken so that was the end of that!

    Like 5
  19. Rallye Member

    This is similar to what I raced in ’58 @the Karting Kettle in Elkhart Lake. Feldman Eng. made “Plymouth” go karts in Plymouth, WI. My dad worked there part time and built mine. A single Power Products would get it up past 50 mph. Photo is from 1960 and there I am way out in front….well maybe I’m in the photo and maybe not? (I have no photos of those days. This photo is from the Wolf family.) The bowl helmet with ear flaps and chin strap like in the photo is what I wore.
    2 stroke single, twin and triple engine karts raced then.
    The Karting Kettle was down in a kettle (See Kettle Moraine) so the sound didn’t bother the village much.
    About 20 years ago, my grandson raced there with a Briggs flathead on methanol on Tuesday nights. His claim to fame was beating Andrew Hobbs (David’s grandson) rarely. David was there as often as he could make it.
    I still have the Comet kart he raced in storage near Oshkosh where there’s a small private track.

    Sadly, there’s an assisted living facility and condos where the Karting Kettle was located. Just North of the Throttle stop.
    As the Karting Kettle was winding down, the kart track at Road America was being built.
    I still race @ RA on the 4 mile track with cars.

    Like 2
  20. Chuck Williams

    I remember those Taco 22’s. C &J Motorcycles in Arlington sold them. They were fast with those West Bend Engines !!

    Like 0
  21. Scotty Gilbertson Staff

    Auction update: nobody plunked down the $3,999.99 opening bid so this auction ended with zero bids. But you’re in luck, the seller has relisted it with the same opening bid price of $3,999.99 and you have another 29 days to kick it around in your head.

    Like 2

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