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Most "regular" Harley riders would probably be shocked to see how high the V-Rod revs in fifth gear at 70 mph. In freeway traffic I'm regularly running between 4000 - 5000 rpm, depending on the flow, and how quickly I want to get past that semi trailer with snarky looking tires. 5000 rpm on an Evolution or Twin Cam 88 would be at or pretty close to redline.

Which makes me think about the talk about a possible sixth gear for our beloved V-Rod. On previous bikes I used to follow the 80/20 rule: I typically never wanted to have my engine running at less than 20% or more than 80% of redline. For a Revolution engine this would mean mean keeping the revs between 1800 and 7200 rpm. Furthermore, it was my preference to try to keep the engine at 50% of my conservative redline. That is, at 50% of 7200 RPM. At 3,600 RPM my engine should theoretically last forever. But at 3,600 RPM on the V-Rod I'm usually going to be blocking traffic (about 59 mph). Obviously this rule is going to have to be modified for long trips on the freeway, where cruising speed usually means 70 mph+

Is a higher sixth gear the answer? I don't think so, and moreover I don't think it is either necessary or a good idea.

First off, the Revolution engine is designed to be a higher revving engine. Dual overhead cams and a relatively short stroke mean that there is a lot less superfluous inertia being created inside the engine. Secondly, the Revolution engine is both liquid and oil cooled. All that coolant wisks away combustion and friction heat far more efficiently at high speed than air molecules rattling over the fins on an air-cooled bike. And it is heat that ultimately destroys an engine - heat that breaks down the viscosity of the lubricating oil, heat that stresses and ultimately distorts the rings and valves.

Secondly, I don't find the Revolution engine to be particularly unpleasant to sit on when its turning at high speed. The engine itself is nicely counter-balanced, and if that wasn't enough the rubber mounts smooth things out even more.

Lastly, I think that a theoretical overdrive sixth gear that allowed you to cruise at 70 mph @ 3600 rpm would drop you so low in the torque curve that speeding up to pass would require a downshift. Downshifts would also be required to make it up even the gentle grades of mountain freeways. Failure to downshift in thse situations with such a transmission would likely risk detonation - far more of a risk to the engine than extended running at 5500 or even 7000 rpms is likely to present.
 

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At or just under 7000 rpm at 120 mph in Fifth gear in my experience. :eek: Of course, that would be an approximation since I wasnt spending a lot of time looking at my gauges on that bumpy ass country road. I'm pretty content with the gearing we already have, dude.
I've been riding with friends at about 60 mph and downshifted to 2nd then slammed the throttle. Holy ****, talk about ass pucker effect.
 

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I have found myself looking for a 6th gear too. It seems as I hit 70 at 4000 PM I just feel the need to find one more gear to cruise in that would drop me into about a 2700 RPM overdrive type feel. Yes it would require a drop to 5th to really accelerate up in a passing gear, but who the hell am I gonna pass at 80, and if so won't dropping down to that fourth gear be fun.
 

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Would it really be worth it? I only ask because I heard of a guy who put in the 6th in a Buell and decided that it wasn't worth the money. It only gained about 5 MPH on the top end (I think), but the price just wasn't cool.

I cruise about 83 MPH at 4000 RPM now. I held that for about 500 miles, not including the obvious fuel stops, and the few runs up to triple digits following a Katana.
 
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