Some time ago, I pointed out Greg Nelson’s V-Quad engine, a pair of V-Twins joined at the hip to create a V4 with loads of power that still managed to look fairly unobtrusive. He mounted one in an old FXRS and rode around quite a bit, using it as his test bed for development. Since it worked so well, Greg built a bigger version and dropped it into a bagger.
As the pictures show, it blends in so well a casual glance would miss the 2 extra cylinders, but when you twist the throttle, there’s no mistaking it. I’m not sure of the exact specs on the engine Greg used in the bagger but the one used by the boys from OCC for the Intel chopper had 214 cubic inches and 250 horsepower. If this one has anything near that, the bagger experience just got a whole lot more lively. The prototype was 160 cubic inches.
I’m a big fan of understatement and I can’t get over how well the engine hides in there, very cool. I’d like to see the look on some sportbike rider’s face when he casually accelerates away from this big old Harley, looks in his mirror and sees the bagger is still there! Gotta love it.
UPDATE: Greg Nelson comments below about his V-Quad.
More photos and links below:
The V-Quad engine that went into the bagger.
Link: Nelson Engineering
Related: V-Quad Follow Up
Mikey says
-THIS- is the evolution of the Harley engine.
Not that it’ll show up on the showroom floor any time soon…
I can only hope the suits notice this and decide to make available a few new custom models. And drop the V-Rod, please? It’s just not “it”.
Sean says
I wonder how he’s aligned the crank(s) and cams?
If you had one front cylinder and one rear cylinder fire simultaneously I would think that vibrations would be lessenned and you would still get a potato-potato sound out of it.
Derek says
I would like to see the same thing but in a little bit smaller displacement, like a Sportster 1200 platform. now that f-er would scream! 2400cc’s in a bike that light. with a v-twin and the right exhaust you can always get the signiture sound. it would make more sence to time it to where they all fire in sequence. i can see a sport bike style like the Wakan 1640 with duel thunderheader’s out back poited towards the sky like other sport bikes.
hoyt says
why drop the Revolution engine when you can put a supercharger on it and get a reliable 180 hp? (not sure how bad it affects mpg)
The Revolution engine needs a different platform. Roehr Motorcycles should make a sport tourer alongside their VRoehr.
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Although this bagger has good engineering and understated execution, it has to be getting close to 900 lbs.
Derek says
since when does Super charger = reliable?
900 lbs easy! + gear and two fatties. well over.
coho says
Harley Apollo, anyone?
Tyler says
Very nice, I am not into the “bigger is better” theme but it is an impressive build.
Hmm, ok its eating me up inside, with the level of engineering that must have gone into this, couldn’t he have reversed the backing plate on the left side carb so that the S&S cover points to the rear?
Nicolas says
It’s the illegitimate children of a Harley and a Vmax ?
Ricky says
Nice ‘thigh roaster’ pipe there.
Nova says
Wow someone just remade the Yamaha Royal Star Tourer. Of course this has a ridiculously oversized engine and uses 20+ year old, slightly updated technology, but what do I know.
Still it’s pretty impressive engineering if somebody has the money and ego to pay for it. Not really on my list of bikes to own tho’.
hoyt says
Derek…I didn’t suggest super chargers were reliable across the board. There are some good aftermarket units out there.
The supercharger that Roehr is using apparently is good enough to not cause him to be concerned. That, and the build-capacity of the Revolution engine can still make for a reliable motor.
There are even auto manufacturers that sell supercharged cars off the factory floor.
B*A*M*F says
Very cool. The carb cover would be nice if reversed. I would also probably personally want the left hand pipe not to be where it is. It just doesn’t look comfortable, which doesn’t make a lot of sense on a bagger.
Otherwise, it’s an impressive feat of engineering and attention to detail.
Prestons says
There are only one set of cams for this engine! I think there are torque tubes going between the front and rear heads to actuate the valves together. Loads on the cams could be large.
This engine needs to run as a “big bang” because of single cam set.
David says
I like this for what it is (very pretty) but isn’t it just reinventing the wheel… Really well sorted back in the 80’s via Honda v65/Yamaha Vmax? He could have just air cooled one with chrome fins knocked off at 4pm and gone for beers.
Mark says
Why exactly did he decide that a Harley wasn’t already heavy enough? If you want to make a bike this impractically overweight and overpowered you may as well do it properly and buy a Boss Hoss. At least then you’re not pretending that you did it out of necessity!
Derek says
have you ever riden a boss hoss? they have two gears, low and high. it is like riding a two wheel sprint car, basicly direct drive. this has the weight and power of a boss hoss, but it has something a boss hoss does not. proper gearing. the load on the cams i think is the big problem. lots of people get pipes for their baggers that have the front pipe come out on the right and the back pipe come out the left with no equalizer tube. this probibly isnt much worse in regards to heat on your leg.
RH says
Why convert an unwanted V65 to aircooling then go for beers when one can just spend all the time and money for beers and make dumb comments on the internet? Doing more than that with time and money is just a waste of life.
todd says
Sure this doesn’t make much sense; woo hoo, the air cleaner is backwards, the rear cylinders will never cool but it’s a custom. Why is everyone so against all the hard work that Greg Nelson did just for the heck of it. I wish I actually did stuff I could show off but then I’d have to listen to all the crap everyone here puts out against it.
And Prestons, no it doesn’t have to be a “big bang” engine because of the cams. The lobes can be timed to the crank shaft, not the other cam lobes. The twin cranks can be in any configuration desired. They just all spin at the same RPM. It would just sound like two harleys running together (which you can hear all the time).
-todd
DJ says
coho: You mean Project Nova?
Prestons says
Todd,
I can see only one set of cams for the left and the right engines in the pictures. There is an empty space for the push rod tubes along the left hand engine’s cylinders. I think the white tubes between the left and right heads cover torque tubes to operate the left engine’s valves. If I’m right, the valves for each engine must open and close together. The engines must fire together. If there were a second set of cams, the phasing between engines could be changed but that is not the current setup. I doubt there is room for another cam set along with the primary drive. It’s a neat package but the valve actuation is not ideal.
BonesDT says
Sean, I like your thinking, but it wouldn’t work the way you describe. If a front piston fired simultaneously with a rear piston, then the next two pistons could not fire simultaneously, killing the potato sound. You would need 2 separate counter-rotating crankshafts like the Motoczysz.
Harley engines make the most amazing sound in the Universe. Two Harley engines firing simultaneously … you do the math!
coho says
DJ,
Yes I did. Apollo was a Duck & I, apparently, am an idiot.
Greg Nelson says
I want to thank all of you that took the time to look at and discuss my V-Quad engine and demonstration installation. I’ll try and answer some of your questions here, but if you have more, contact me on my web site, http://www.v-quad.com or call me at 916-417-5871.
First let me explain the design of the V-Quad. I’m not sure that “Big Bang†is technically correct, but it is reasonably accurate. The single crankshaft has 4 flywheels and the rod journals are in the same plane. The front pistons and rear pistons move and act in unison. As an Evo* style engine it only has one camshaft and it opens all the valves, front cylinders at the same time and rear cylinders at the appropriate time which makes the firing like a stock H-D*. Certainly the valve spring loads on the cam and lifters were a concern. So as to not exceed appropriate design limits, I reduced the valve spring pressures and limited the RPM to 5,000 maximum. This results in the same cam loading as a high lift cam, heavy springs and high RPM engine. The rocker drives across the top of the engine transmit motion along with oil to the left side of the engine. Since the 4 cylinders behave as 2, the ignition is standard crank trigger electronic with a four tower coil, giving the famous V-Twin sound which is part of the extensive V-Quad patent.
As for the heat rejection, here’s the story: Unless you are hard into the throttle, which you can only do for a few seconds due to excessive speed, you cruise at the same power output as any engine – only the V-Quad has twice the cooling surface to keep it cool. Additionally, more than 1 ½ hours at 1 to 5 mph at the H-D 105th Anniversary in Milwaukee demonstrated no heating issues.
The air cleaners certainly caught everyone’s attention – that was what I wanted in this demonstration installation. The entire left set of cylinders is 100% interchangeable with the right set. The V-Quad “KISS†design uses only 16 special parts.
By the way, a twin turbo 350 bhp bike with a V-Quad engine was picked as “Americas Most Beautiful Motorcycle 2008†at the Pomona show in January. A supercharged version has been under construction for several months now.
The bagger shown is 214 CID (3507cc) and was run on a chassis dyno and produced almost 150 bhp and 180 lb-ft of torque. At only 8:1 compression with a no-lift cam (Andrews EV51) this engine will run all day long without being overstressed. The engine is only 3†wider per side than a stock engine and puts the extra 150 lbs at a low center so that this bike handles as well as any bagger.
Contact me if you have more questions or want clarification on any of these details.
Greg Nelson
todd says
I was thinking of an overhead cam. You’re right, I forgot temporarily about push rods. If this did have overhead cams you wouldn’t have to worry about timing the two cranks together. Actually you could offset the phases so that there was only just as much strain on the valve train as a stocker, only twice as often.
I think of the irony of building a 150HP bike and then reducing the output and cruising at the same power as a stocker.
-todd
Patik says
TODD wrote: “I think of the irony of building a 150HP bike and then reducing the output and cruising at the same power as a stocker.”
I would like to put this like this: Irony is buliding a high output hp bike and then reduce the power TO 150HP.
Patik says
BTW. a “twincam” setup with evo cams and a reworked rockers/housing could decrease the strain on puchrods and cams without increacing the with of the engine. 8 sportstercams would be the coolest though. 8 cams and just a slight ignition/crank offset, just a couple of degrees would make a intresting sound and would probably put less strain on the transmisson. The swedish truckmaker (lorryes) Scania has found that gearboxes takes more tourqe from a V8 and then from a straight-6. These are big engines (up to 16.000cc) with loads of flywheel and rotating mass, so one might think that the pulses from the engine sould not matter that much. But it does.
mickyc says
derek.why put 2 sportys together just buy 120 ci sporty from zippers put in buell and have 180 hp motor in 180kg frame!!!
hogfest50 says
ALL GREAT STUFF LOVE TO SEE THIS I WAS BROUGHT UP ON THE CRAP PRODUCED BY BRITISH BIKE MAKERS IN THE 60S AND 70S EVEN WITH GOVERNMENT BACKING AND THEY STILL GOT IT WRONG BUT THESE GUYS HAVE GOT IT RIGHT I OWN A STOCK HARLEY AND LOVE BIG KEEP UP THE GOOD WORK GUYS I’LL BE WATCHING