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Around 1980 someone in California modified a CX for half mile and dirt track racing. He rotated the engine ninety degrees and converted it to chain drive. A couple of magazines reported and had photos of this bike and similar others. Does anyone have those magazines or any photos of that conversion?
 

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THIS is the closest I can find right now.
 

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It was wonderful! For years Hogly had owned the dirt politically by getting their 'AMA' branch to outlaw multies,cammers,or any thing that was potential competition! I don't recall how honda got in but they dominated for a few years and after proving their point gave the dirt back to H-D. Ever see the 2 Aermacchi twin cam single road racers-1 in house built and the other developed by an employee? When Hogly took over in early 60s they banned any engine that didn't have 'PUSH RODS'! I worked part time at a Hogly shop while in college during the 60s and learned to disdain them. When AMF took them over their brilliant engineers tightened the end play on the tranny shafts and every Sportster made that way seized its gearbox! The owner of that shop changed to selling BMW. He is in a nursing home now but when I visited him last month we joked about that brand and how when their terrible shaking breaks them in two going down the road the dying rider will crawl over and kiss the broken parts as he draws his last breath. GJ
 

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Is the benefit to running these sideways with a chain that you can then modify the gearing easier?
 

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It would remove some weight and there is some loss of torque in a shafty vs a chain. The more gears you have together, the more slop you have which translates to inefficiency.
 

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a while back i saw an adapter that someone machined up that attached at the engine and allowed them to run a chain. i've looked for it since and haven't been able to find it. i wish these bikes were chain driven. it would give so many more options. and a better transfer of power.
 

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a while back i saw an adapter that someone machined up that attached at the engine and allowed them to run a chain. i've looked for it since and haven't been able to find it. i wish these bikes were chain driven. it would give so many more options. and a better transfer of power.
Look under "JimL" 's posts. Jim races CX500's and CX650's at Bonneville. This swap is only practical for a racer who plans to build a custom frame and swingarm. When you see Jim's bike it barely has any parts that came stock on the bike. Everything from the frame, to virtually all of the engine has been redesigned. Jim has had to custom order or fabricate the entire bike as no one has parts for a CX Honda with an engine that is turned 90 degrees. Oh yeah, he holds a bunch of records and his bikes run like stink.

Ed
 

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Reading his posts, he blew me away. There is the general mechanic, then there is this guy who would spend bucks to loose 5 pounds and put the bike in a wind tunnel with his custom fairing. He takes performance to a whole new level.
 

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Look under "JimL" 's posts. Jim races CX500's and CX650's at Bonneville. This swap is only practical for a racer who plans to build a custom frame and swingarm. When you see Jim's bike it barely has any parts that came stock on the bike. Everything from the frame, to virtually all of the engine has been redesigned. Jim has had to custom order or fabricate the entire bike as no one has parts for a CX Honda with an engine that is turned 90 degrees. Oh yeah, he holds a bunch of records and his bikes run like stink.

Ed


this wasn't jim's bike. this was a regular old cx500 (engine mounted the standard way in the stock frame) but it had an adapter where the shaft comes out that had a sprocket attached. can't remember what swingarm they put on the bike... but they did have a chain running to the rear rim. and this swap i'm talking about is practical for more than just racers. the ability to mix and match more parts... running a chain where you can swap sprocket sizes for highway running if you want... the practicality is pretty endless.
 

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Hate to bring back an old thread, but I was wondering instead of chain drive, any way to mount a belt drive? I was actually thinking of putting in a different engine but it's chain driven, and not sure how I'd have to go about the rear brake and swingarm.
 

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The CX engine is what is called a "stressed member", that is it forms part of the chassis structure. If you were to put in a different engine that was not designed to be part of the structure the work you would have to do to make the frame strong enough to support it would probably be more than building a new frame. If the engine you want to use is a bike engine you would likely be better off to find a frame from the bike it came from in the first place.

If you did rebuild the CX frame to suit an engine that was designed for chain or belt you would need to replace the swingarm with one that does not have a Final Drive and the wheel with one designed for a sprocket and it would make sense to use the brake that fit that wheel.
 

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It's difficult to pair two 650s in a frame without going chain drive. That was an amazing feat!
 

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In my opinion the shaft drive is one of the big pluses of these bikes. I have no problem with power loss issues and am currently shreading some very big V twins. I accept some power is lost BUT if you ride like me the cost of changing chains and sprockets regularly would be far worse than the minimal power gain offered.
 
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Search here. youtube Honda NS750 1981 AMA Dirt Track Racing Bike.
For some reason I can't paste a link up.
 
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