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The Revolution X is a 749cc four-stroke engine that is configured as a liquid-cooled 60-degree V-Twin with chain-driven single overhead camshafts (on per cylinder) operating four valves each. The RevX also gets roller rockers with screw adjusters, keeping with the current trend of friction reduction. A lot of work on this engine was done by AVL, but this construction format is actually very similar to the V-Rod which came in 2001 bearing a huge Porsche influence as Harley's first liquid-cooled engine and motorcycle.



Harley has moved away from tradition with the RevX engine. For example, the 60-degree included angle of the V -- 45 is the traditional angle -- was used to lower the height of the wet sump engine. This helped to create the low seat height. It also lowers the center of gravity which makes the handling better and low speed feel more secure and stable, all critical elements for new riders to be able to find confidence in their machines.

Above the crankcase are two separate aluminum cylinders with iron cylinder liners. In fact, the sole difference between the 500cc and 750cc versions of the Revolution X is the bore. The 749cc uses a 85mm bore while the 500 uses a 69mm bore. Both have a 66m stroke. Both engines have the same 8000rpm redline with the 750's peak power likely to be just under 55PS at about 7500rpm. Torque is claimed to be 65Nm at 4000rpm, which promises quick acceleration as well as the typical rideability that Harleys are famous for.



The Revolution X will be built in India and currently the Indian 500cc plan is on the back burner. The Street 500 is being built at the Harley plant in Kansas City for domestic consumption in the USA. Harley India will export the Street to three European countries initially with exports to SE Asia are soon to come.
 

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The Revolution X will be built in India and currently the Indian 500cc plan is on the back burner. The Street 500 is being built at the Harley plant in Kansas City for domestic consumption in the USA. Harley India will export the Street to three European countries initially with exports to SE Asia are soon to come.
Really thats the only part I'm interested in considering that is different than the story to date, however I'm also fairly certain that you've made a mistake. I'm not sure who your source is but it seems to be from India. So yes its likely the Indian made Street 500 will feature a built in India 500cc revX...
 

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The Evo-X engine has cylinders that are separate castings from the lower case and the heads, and cast in iron liners for the cylinders. On the V-Rod engine, the aluminum cases extend all the way to the head and the cylinders are steel wet sleeves held in the cases with o-rings, much like those in a big diesel engine.

Another difference between the V-Rod and this engine are the cam drives. If you look carefully at the cylinder heads you can see the front head has it's sparkplug located on the left side of the head casting while the rear cylinder has the spark plug located on the right side of the head casting. This tells us that the cam chain for the front cylinder is on the right side of the block and the cam chain for the rear cylinder is on the left side of the block. This is exactly the same as a Yamaha Virago, Buell Helicon engine, several Rotax watercraft and snowmobile engines and before any of these, the Harley Davidson 1100 OHC prototype that never made production. V-Rod engines place both cam drives on the left side of the engine and the spark plugs are centrally located in the combustion chamber.

If you look carefully, it appears to me the front and rear heads use the same casting but they are simply oriented 180 degrees apart on their respective cylinders. This would make a lot of sense from a cost savings standpoint. V-Rods use dual down draft throttle bodies and velocity stacks with an injector in each intake. From what I can read about the Street, there is a single TB and one injector for both cylinders, a huge kludge in my opinion.

You can also see a coil on the left side of the bike where Harley usually places the horn. V-Rods have coils built into the spark plug cap. Coolant hose routing is very different from that of a V-Rod so I have to suspect a different coolant pump location.





And the original VR-1000 race bike engine, from which Porsche Engineering developed a workable and reliable steet engine for the V-Rod.

 

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I like this:

1. The Revolution X’s voice

The RevX doesn’t start out very promising. When you’re trundling through a hotel forecourt it makes more of a transmission whine than any other sound as long as the revs are low. In fact, if you read a reference to how the Street sounds like a Japanese twin, chances are the rider didn’t get enough to ride the motorcycle.


Because the action really begins once you hit 35-40kmph or in revolutions per minute terms, you cross 2000-2500rpm. Yes, there is no tacho on the motorcycle so I am intrapolating back from the 8000rpm redline. At these low and middle revs, the RevX actually sounds like a honest to goodness scaled-down V-Rod. Which, of course, in many ways it is — the two engines are both liquid-cooled, 60-degree V-twins and while one was developed with Porsche, the other was developed with AVL etc. The distinctively American V-twin sound is there though muted to meet our sound emissions. To be fully clear, you’ll hear the note a lot better if you’re a Street 750 than if you are on it, something I imagine an after-market exhaust will fix.
thanks for the link sunny!
 

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Heres a comparison of the Harley Davidson Street 750 against its competitors (Yamaha, Star, Ducati, Iron 883 etc)

DYNO TEST

Dyno Files: 2015 Harley-Davidson Street 750 vs. The Competition

Its impressive how Street 750 stands its ground !!!
I find it impressive how linear the power delivery is just pulling and pulling until the top, flatest torque curve in the league! Star Bolt is so peaky, although the monster does look pretty good as well, too bad the bike is ugly as virtue and costs 2K more!
 

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Really thats the only part I'm interested in considering that is different than the story to date, however I'm also fairly certain that you've made a mistake. I'm not sure who your source is but it seems to be from India. So yes its likely the Indian made Street 500 will feature a built in India 500cc revX...
500cc is not gonna get launched in india atleast for a year and a two as per the dealers
 

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I think the soonest we can see a 500 launching in markets where it's not originally launching in but rather the 750 is another 6 months at minimum if we're lucky
 
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