Wednesday, March 16, 2011

Royal Enfield with Yamaha twin is fast, looks right

Enfield with heart of a Yamaha 650 twin.
Update: This item has sparked discussion of homemade Royal Enfield twins, Yamahas, parallel twins and V-twins. Check the "Comments" link at bottom to get in on the conversation.

Royal Enfield is considering building a more powerful motorcycle, with a parallel twin motor like those in its legendary Meteor and Interceptor of the '50s and '60s. No sooner did I report that than this message arrived:

"Sorry but I couldn't wait for a parallel Bullet so I modified mine. I like it specifically because it's NOT another V-twin and all the hoopla that goes with 'em," wrote Gerry from Washington state. He attached this gorgeous picture of his Bullet with its parallel twin, transplanted from a Yamaha 650.

Enfield-Yamaha looks right.
The picture is out of date now, as Gerry has continued what he jokingly calls his "sacrilegious mods" to his Bullet.

Also out-of-date but still inspiring is this Youtube video of Gerry taking a brief run with the then still unsorted Yamaha Bullet.

His comments on his video explain the project pretty well:

"Bought a parts bike for $100. Original Enfield motor with very high millage, still intact. Rebuild might have been cheaper, however this one can cruise all day at 90-100 mph after I put the Yamaha swing arm and rear wheel into it.

Gerry and his Enfield-Yamaha twin.
"This thing buries the speedo needle with ease and accelerates like a GSXR 750 and shoots right over the Rocky Mountains like a cannonball."

He credits fellow bikers on the Royal Enfield Forums with helping along the way and inspiring him to keep going. "Learned much from the good people there," he wrote me.

One picture on the Forum shows the subframe made for his Bullet twin.

Custom cradle supports motor better than brackets alone might.
"This was made to enclose the gap in the frame that is normally underneath a Bullet motor and transmission. Its purpose was to provide extra support to the front down tube, neck and back bone. Also provides a fifth 'engine-to-frame' mount and a spot to hang the Enfield footpeg assembly."

In comments on the Forum, Gerry expressed doubt that Royal Enfield itself could ever successfully sell the fast parallel twin he wanted. How could an Indian twin overcome the Brit-bike snobs and the American prejudice for V-twins, he asked? Besides, he noted, there is no shortage of reliable old Japanese motorcycles available in the U.S. to meet any demand for conversion to fast café racers.

At the same time, he hopes he is wrong about a new Royal Enfield twin someday coming to America.

"I would like to build another single using the Ace/Chumma Fireball and yes: if I can afford it would LOVE a new stock twin."

As for what he did being sacrilegious, he's prepared to take the criticism. Still, "don't think I would have stuffed a XS650 motor in a real '58," he wrote on the Forum about such a bike on eBay.

Winston Churchill packs a Tommy gun on rear finder.
As for the future: "My plan is to ride the hell out of my Bullet and keep messing with that for a decade or two."


  1. Looks great! I hope Enfield releases twin engines that can be purchased separately to fit into my Classic Bullet. As much as I appreciate the new Bullets, I'd really rather just keep mine, drum brakes and all - a twin engine would be a perfect mod!

  2. that is a gorgeous machine, great job!

  3. Matt Law3/09/2011

    I've been watching Gerry's mods for a while...his hybrid is a BEAST...

  4. Not "sacriligeous" as neither donor machine is "sacred." So it's a no-harm no-foul deal as far as I'm concerned.

  5. Anonymous3/11/2011

    WOW, nice comments. Thank you. I was expecting more haters. Thanks again Dave, Gerry

  6. Thank you, Gerry, for making this motorcycle happen and then being willing to let everyone else see what can be done.

  7. Fantastic job Gerry! You put together two of my favorite bikes- the Yam 650 and the Bullet.
    I have 3 Yam 650s which I think have the same addictive 'just-rightness' as the Bullet.
    Even though you don't like V twins, I do hope the Musket v twin (with a Fireball job) may meet with your approval!
    All the best and enjoy your ride.

  8. Anonymous3/14/2011

    Aniket! Damn...I am remiss in mentioning my profound interest in the 700 V you designed on CAD. I have private messaged you even about it though you must be virtually inundated. Your engine's voice reminds me on the famous Vincent and who could not be amazed at such a feat of engineering by a single person. My hat is off to you. A V-twin with a pair of heads flowed by Joe Mondello, fireball would be a 1070cc fire breathing 100+ hp MONSTER. Is like comparing VW Beatle to Mercedes Benz. What great luck that you are in proximity of Ace and Chumma. Absolutely there is an exception everything, epic job on the Musket. I am honored at your reply. This XS came my way at the right moment both for my Bullet, mechanically ability, and unfortunately my current price range. It is a solution, not THE solution. So yes indeed there is a V twin I would love to own. Best wishes, Gerry

  9. the XS650 happens to be the most beautiful motor according to me. clean, balanced and proportionate. i wish they had built the new UCE as clean and balanced. i see too much clutter in it. hope RE makes the new twin motor a parallel one as opposed to the V, and hope it looks as good as the XS 650 motor.

    that said, what you have made is the best of both worlds. the bike looks awesome. absolutely perfect.

  10. Anonymous3/14/2011

    I'm glad you like. The resurgence of the XS650 is cool to watch isn't it? While "American built" bikes continue to rise in cost with few innovations the home built alternatives really become a necessity. Manny very interesting projects will fill the vacuum and I enjoy seeing the creativity. I myself robbed this idea from an unknown mechanic who has done this before. Maybe it was for the best I couldn't ask him directly how to do it seeing only that it could be done. Was all a matter of the timing for me as my main mode of transportation was running up in mileage. Still happy with the results and appreciate your comment. Long live RE's XS650's and all other alternative bikes.
    Thank you, Gerry

  11. Hope David doesn't mind us yapping about a non-Enfield on his blog! Have to tell you guys my 650 tale- 2001, just finished gradschool, no job, 9-11 had happened, times were really tough. I was in L.A., staying with my bro, looking for design jobs, seemed like the worst time to be looking. And my dream of having a cool old bike with a twin cylinder motor was evaporating.
    Months of scoring the classifieds for an XS (the only truly classic twin for not much money) finally led to an ad for one in La Habra. It was a LONG bus ride away, I was new and clueless, got off at the wrong stop WAY too early, ended up walking about 8 miles, quite lost. Finally got there, it was in a trailer park and was in complete shambles. Had no brakes, no signals, no exhaust, no ignition...but after that walk, I was just too annoyed to walk away. became mine for the grand sum of $150. Months of frugal Ebaying later, it was done, on a very tight budget. Ran great, but a bit rattly in the top end due to loose pistons. Blissful rides with wide grins down Sunset Boulevard...aah, felt like being inside a movie.
    Got a job in Columbus, had to move, left her behind with my bro.- no money to ship it. But...a few months later I did! She came from L.A. to Columbus on a truck, got her pistons replaced and is still running great, 10 years later.

  12. Anonymous3/15/2011

    Thanks for putting up with us David. I can't pass up the chance to chat with Aniket. I'm amazed at what people can do on a shoestring and your story is no exception.
    Your engine case design utilizing Royal Enfield parts is genius. I had a couple questions about the rods...did you use a longer rod journal (and widen the cases accordingly) and use 2 alpha bearings? Will the crank line up together in the RE flywheel tool? Awesome configuration on the valve train by the way.
    I am hanging on to my old motor and 4-speed. It has well over 20,000 miles on it but still runs. I keep scouring the local net for a 500 with maybe a a blown bottom end. Then I would have 2 top ends, trans and a chassis, with the idea of having real extra money someday...who knows. Your v-1000 would make the best sidehack hauler. Enfields are mostly touque. Without the fireball set up a v-1000 would have say 45 ft lbs at around 3500rpm ? I do like the fact that your making the engine case available as a part or kit. Will you also be offering complete engines?
    If Royal Enfield builds the next twin as a parallel do you see any potential for upgrades or possible designing high performance parts? I guess we will have to wait and see what comes out. Damn...ugh...I suppose thats more than a couple questions. Its just that I been watching your progress for so long. Sorry, couldn't resist.
    All the best to you, Gerry

  13. Hi Gerry!
    Ask all the questions you want! I'm so sorry if I missed replying to your email- please write again, I will be glad to talk!
    About your queries-
    1. Yes, a longer crankpin was made to accommodate two conrods. The 700 prototype that I'm currently running was all stock- so the rods are the alloy ones and the big end is the bush- this was primarily because of budget reasons. Ofcourse, the motor can be assembled with carillo rods and alpha roller bigends too, depending on the customer's requirements.
    I haven't used the RE flywheel tool- I trued it up in the traditional way on a lathe, so I can't say. Just factor in that the flywheels are about 1" further apart compared to the single.
    I'm certainly going to do all I can to accommodate different requirements, incase someone wants a complete assembled motor, and later on, perhaps even do the whole installation and frame mods, which would require the bike or frame to be sent to me though.
    I'm keen to see what RE do with their parallel twin too, let's see :-)
    Great to talk with you and write any time!

  14. Anonymous3/17/2011

    I think the stock rods would be fine in the 700 myself. The hp should accommodate much higher for gearing. What final drive sprocket did you end up running with? Had chance to Get her on a dyno? I think the V with as manny stock RE internals would be much more in the price range of someone such as myself. Will there be a assembled bottom end, or "short block" so to speak, available? I bet the torque/hp increase is more than sufficient for my ridding needs. Would have to be content without the Hi-po mods. 1st anyhow. Most curious if a dyno will verify that it is indeed a cross country highway cruiser as I suspect it is. It most definitely has a nice lazy rumble at idle and with xtra piston much less worry of lugging. Awesome chatting with you Aniket...and ya ...I can't wait to see what RE does with the Parralell. The more the better =)

  15. hey buddy what a magnificent machine....superb...
    done a gr8 job

  16. Hi, just had a view. it's a lovely beast. As you said speeding like a cannonball. see, enfields are OLD bikes on indian markets now. new enfield market is made for bourgeois kids, upper class pune or mumbai flock.
    many of them transformed their RE and said " I try to keep it a close to the original". But WHO told you you had to do or think like that. Do you know the job of anicket vardhan. He created a new srank box with two engines, 700cc now 1000cc and selling kits guys. Well, the guy want the bike look like the original. He even started to give it the name royal enfield (now found the musket name).
    hell with original enfield shape. Enfield itself has evolved and modified models. Who are we to be more royal than the queen.
    go F 'em all, RIDE IT.

  17. This is weird, my brain cannot process this change, enfields are pure motorcycles they don't just make engines there is sense of development of a certain motor feeling when we ride that feel enters the body.


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