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Quote:
Originally Posted by jailbird_fynix
(Post 4609100)
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Looks like a twin engine design? I’m in a lot of confusion. Whether to wait for the updated classics or go with the 650 twins. I’m also in love with the Himalayan; but for the 411 cc engine. If they come up with an Himalayan that produces around 40bhp, I’d like to consider that for the Chennai Bangalore trips (coz I can confidently off road in Bangalore).
Quote:
Originally Posted by Sutripta
(Post 4616038)
You are right about the pushrods. Lots of misconceptions in this forum about pushrods, DOHC, and SOHC.
Regards
Sutripta
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Himalayan has a 410cc OHV engine and doesn't have a thump. Wondering how the new 350cc featured here is going to have one.
My technical knowhow is limited to reading stuff online, forgive me if it's a dumb question.
The Himalayan (and the twin) have a SOHC head.
If you could take a RE CI engine, jury rig some setup, Pushrods, SOHC, DOHC, Solenoids, whatever, to operate the valves maintaining original valve timings, and keeping everything else the same, you would get the original thump.
It is useful for brand recall. And in that worth it's weight in gold. Much like Bajaj's multiple plugs. Or Ducati's desmo setup. Technically dubious, but great for advertising.
A modern engine is very unlikely to produce that thump. Also there are noise pollution norms nowadays. But sound is an important emotive aspect, esp so with RE. So I think some R and D effort would have gone into getting something acceptable but different from the thump soundwise. Maybe RE will try singing a different tune. Amongst bikes sold in India, the Benellis sound great. Whether by accident or design I don't know.
RE has its work cutout. Otherwise as just another 300+ single cylinder, it is very likely to loose it's identity.
Regards
Sutripta
Quote:
Originally Posted by Motard_Blr
(Post 4615973)
The thump is not a result of the pushrod setup. A bit of trivia I learnt just a few days ago: Vehicles in Britain used to be taxed according to the bore size and not according to the total displacement. This resulted in a variety of very long stroke engines in both cars and motorcycles. Technology at that time did not permit high engine speeds with long stroke engines because of the limitations of materials and processes used. So most engines were slow speed by modern standards, and required heavy flywheels to maintain momentum. Pushrod valve train was the most common technology at that time. Chain-driven valve train was reserved for racing engines. This then is the reason for the thump - a deep bass, slow engine beat.
Also note that had RE continued to be in business like Triumph, Norton, etc. They too would have moved on to more modern designs to keep up with the competition.
In my opinion, RE are very aware of attraction that "The thump" holds for loyal bullet fans and they wouldn't want to upset their loyal fanbase. So their new bike, if it's going to be called "Bullet", will have to be similar in character and sound to the existing bullets.
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You are absolutely correct.
The British taxed vehicles based on their calculated horsepower but their method of calculating horsepower was more than a little unusual.
The formula used was, 2/5 (D squared) n = HP or 0.4 (D squared) n=HP
where D=size of the bore in inches and n= the number of cylinders.
Notice that because the size of the bore is squared, a little increase in its size makes a big increase in the final answer. Also notice, the length of the stroke doesn't have anything to do with the answer.
This drove the engine designers towards using the smallest bore that would produce any useful horsepower coupled with a very long stroke to give the engine enough displacement to produce enough power for the job at hand.
A long stroke engine can not rev as high as a short stroke engine and runs best at low RPMs. This is the reason for the old British engines long stroke, thump, thump, thump sound we all love to hear.
This method of calculating horsepower also gave some pretty silly answers.
Take for instance a 4 cylinder engine with a 2 inch bore and a 3 inch stroke.
It's RAC horsepower would be 0.4 (2 squared)4= 0.4(4)4=6.4 horsepower. Notice, if we increase the stroke to 5 inches, the answer does not change.
A increase in the bore size to a 4 inch size gives us 0.4 (4 squared) 4 = 0.4 ( 16) 4 = 25.6 horsepower.
Next-gen Royal Enfield Thunderbird caught testing
A video of the next generation Royal Enfield Thunderbird has surfaced online. It gives us a better look at the changes made to the new bike.
Looking at the video, it seems like the new Thunderbird is likely to switch to a double-cradle frame. The test bike has telescopic fork suspension at the front and twin shock absorbers at the rear. The engine, crankcase and the exhaust are finished in black. Unlike the outgoing Thunderbird, the disc brakes are mounted on the right hand side, while the chain sprocket has been moved to the left. It does not have a kick starter, indicating that the bike might be offered only with an electric starter.
The test bike has a split seat with a split grab handle and a circular tail lamp at the rear. The front foot pegs appear to have been positioned further ahead. The bike appears to have a redesigned headlight, side panels and front and rear mud guards.
The new Thunderbird is expected to be offered with updated 350cc and 500cc BS-VI compliant engines. Dual-channel ABS is also expected to be offered as standard.
https://www.youtube.com/watch?v=qoV1Ln3Oo_E
Source: santhosh kumar / Youtube
Link to Team-BHP News
Another thing evident on both the bikes is the "Double Cradle Frame" which is a new thing altogether from RE. This setup looks like the engine is no longer held as the stress member in the bike instead its sitting happily on the cradle frame. This will definitely solve the vibration of the engine getting transmitted to the handle bar, ending up in the skeleton of the rider. cpics:
PS: I like the way of the brake lever activation no longer fouls with the ground while taking right hand side slanted maneuver .
Got to know from the guys at SVC, the new frames are modified versions of the 650 twin's dual cradle frame. The engine does not have push rods anymore, they have a SOHC cofiguration with a counter balancer.
Will be BS6 compliant and will launch next year before the new norms kick in.
With the push rods gone, I wonder if there will be any "Thump" left in them.
2020 Royal Enfield Classic spied on test cpics:
Source
More images: Royal Enfield Thunderbird spied
More images of the next-generation Royal Enfield Thunderbird have surfaced online. The latest images reveal the bike's new instrument cluster.
The next generation Thunderbird is likely to get a new single-pod instrument cluster that has a small digital display. Besides this, the test bike has black alloy wheels and redesigned chrome exhaust. It also has a shorter rear fender with circular tail lamp and turn signals.
The new Thunderbird is expected to be offered with BS-VI compliant 350cc and 500cc engines. The bike is likely to get telescopic fork suspension at the front and twin shock absorbers at the rear. The test bike is also equipped with disc brakes at both ends.
Source:
Bikewale Link to Team-BHP News
Personally I am very excited about this. Here's why: I am a big fan of the classic motorcycle shape, you know the traditional shape. Not sportbike, not cruiser, not adventure, an old-school motorcycle shape. It works well not only for rider ergonomics but also is very useful in India for family people, with regards to pillion seat height and slope. Our previous generations had a lot of options in this space, like the RX, KB, RD, Rajdoot, Suzukis and so on.
Unfortunately we have very few bikes satisfying such a wide need now. I was excited for Jawa until I saw the tiny pillion seat. It is such a missed opportunity in my opinion. Other than Royal Enfield, if you want a usable family bike then you have to go for something like a Splendour or an Activa (coincidentally guess what sells really well - RE, Splendour, Activa). Even the likes of Pulsar and Unicorn have relatively raised and sloped seats, the same can be said of Dominar or Mojo. Cruisers don't work for me either, with that unnatural riding stance that is better for posing than anything else. I don't understand how product heads at motorcycle companies fail to recognize such a basic need. In a country where ladies still sit side-saddle, isn't it kind of obvious?
Anyway, this bike looks all-new including the engine case. If the 650 twins are anything to go by, modern Enfields will be good - not just relatively good, but actually good. Hope so, let's see. Fingers crossed.
I think the RE is doing really well. Saw five of these bikes standing back-to-back, for tank protectors on JC Road. The bike has solid presence. ABS in big and bold too. I saw one with a solid brass 'Indian Army' motif being mounted, and the guy was 'as civilian as civilians go' (asked him in fact, much to his embarrassment). LOL
Quote:
Originally Posted by tchsvy
(Post 4674826)
Few more Thunderbird test mules, courtesy rushlane. I guess RE is experimenting with different exhaust setups as can be seen in these pics.
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The exhausts look the same on all bikes, except that the coating is different. Matt and chrome.
The length of this exhaust reminds me of the 2004 Electra were they launched a glasswool muffler which was short compared to the long ones seen on the Classics and Bullets now, which was originally seen from 2002. They need to invest more on acoustics.
Hate the back of the new Thunderbird. It looks like the one from the Imperiale. Also the lovely projector headlamp and the ring drl seems to be history. In my opinion the current Thunderbird seems to be the best looking 'RE out there and has massive road presence. Even more than the Interceptor. Am at crossroads. Should I buy the current Thunderbird which hopefully after being for 8 years on sale has lost all it's flaws. Or wait for the new one which going by the test mules I don't like that much. Or buy the Interceptor and make it touring friendly. Too much to think about !!!
More images: Next-gen Royal Enfield Thunderbird spied
New images of the next-generation Royal Enfield Thunderbird have surfaced online.
The spy images suggest that the new Thunderbird is likely to get a smaller round headlamp with a circular instrument cluster. The bike also appears to have a new fuel tank, redesigned side panels, stepped seat with split grab rails and a new circular tail lamp. The test bike has black alloy wheels, a front crash guard and a saree guard.
Reports suggest that the new Thunderbird could come with a 400cc engine, which could replace the 350cc and 500cc units offered on the outgoing model. It is expected to get disc brakes at both ends and dual-channel ABS.
Source Link to Team-BHP News
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