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I have heard a year or so ago that the new yamaha R1 is a inline 4 cyl engine that fires 2 cyls at a time to achieve torque or a v twin.
Has anyone heard of this to be true and more importantly have experienced the newer yami R1?????
thanks,
Nivek
"if you arn't riding like your on rails, then your sight seeing"
Kinda... and yes...
Wanna buy one?
LRRS/CCS Amateur #514 / RSP Racing / Woodcraft / MTAG Pirelli / Dyno Solutions / Tony's Track Days / Sport Bike Track Gear / 434racer / Brunetto T-Shirts / Knox / GMD Computrack
I wouldn't mind trying one out but i'm addicted to my buell lol
Nivek
"if you arn't riding like your on rails, then your sight seeing"
Right, but the torque is what i am interested in.
I love my 1125R and one reason for it, is the torque curve is one of the flattest. So, i am interested in if they are firing 2 cylinders at the same time, is there a notice power difference than a typical 4 cylinder?
Nivek
"if you arn't riding like your on rails, then your sight seeing"
Search for cross plane engine/ big bang engine. Happy reading.
The way the engine develops power is by changing the mechanical pulse of the engine via firing order and crank timing when compared to a "traditional" I-4.
Last edited by butcher bergs; 02-16-10 at 09:02 PM.
Hmm, thanks Bergs, the new engine is interesting,
sry r7 your comment went over my head, i didn't get it.
This has been the first time i have heard of the referencing: big bang theory or cross plain engine.
I've read the concept before in generic engine layout articles.
Nivek
"if you arn't riding like your on rails, then your sight seeing"
Not sure what the exact torque is, guessing it's somewhere around 80-85 ftlbs? Never dynoed the bike or researched it, but it is NOTHING like the last generation i4 R1 according to my ass dynoIt pulls much harder at low RPMs vs the older one. I had an 06 R1 before the 09.
Just a little more engine vibration than I like, but i'm sure it's nothing compaired to what you're used to![]()
Yamaha
What yamaha is doing is not a Twin Twingle or Big Bang motor, the cylinders aren't firing twice at a time, but they are firing closer together in clusters.
This thread is full of LIES
the R1 uses diesel fuel now
and it releases water vapor only!!!!!!!!!!!!!
yeah, the article i was reading says it has the pistons off of each other by 90 degrees, this would create more a cluster firing and would account for the extra vibrations. My bike vibrates bad . . . the girls never complained tho, hmm
Nivek
"if you arn't riding like your on rails, then your sight seeing"
it's more akin to the following:
BOOM--------------------------BOOM-----
-BOOM--------------------------BOOM----
--BOOM--------------------------BOOM---
---BOOM--------------------------BOOM--
instead of what you were thinking of it being more like
BOOM-----------------BOOM---------------
------------BOOM-----------------BOOM---
BOOM-----------------BOOM---------------
------------BOOM-----------------BOOM---
Last edited by spicy; 02-17-10 at 04:09 AM.
hurray, strikethrough!
...adventure timeadventure time...adventure time...adventure time
The firing of the cylinders is not what causes vibration. The vibration you feel is caused by the imbalance of the reciprocating assembly. On a "normal" inline 4, the crankshaft counterweights for cylinders 1 and 4 are perfectly offset by the coounterweights for cylinders 2 and 3 at 90 degrees BTDC and 270 degrees BTDC, because they are exactly the same mass and 180 degrees out of phase.
The Yamaha cross plane engine does not have this perfect primary balance. The counterweights are remarkably different in mass and not 180 degrees from each other. If it does vibrate more than a "normal" IL4, this is why. That said, it may not vibrate more, just differently.
"Normal" IL4 may have perfect primary balance, but they have awful secondary imbalance which is why they typically come equiped with a counterbalance shaft(s) running at double crank speed. The secondary imbalance peaks occur at 45, 135, 225, and 315 degrees BTDC. With four peaks per crank revolution, you can understand why the countershaft(s) has/have to run at double speed.
This crankshaft design does not affect peak torque at all, that's a function of displacement and bore to stroke ratio (assuming induction and exhaust systems are optimized for the application). If the engine makes more torque down low, it's only because it has been tuned to do so. The same exact torque curve would happen with a "normal" crankshaft in the same engine. The design only affects the way torque is delivered to the rear wheel in the short time it takes for the crank to make two revolutions. A dyno graph cannot show this difference. I can only imagine Yamaha did this for traction purposes coming out of corners, The grouped pulses load up the rear tire hard and then the long period between the groups gives the tire a chance to recover from the load. This is precisely why Honda used a similar approach in their NSR500 two-strokes back in the 90s.
This is also why singles and V-twins are so widespread for off-pavement use (note the success of the Harley XR750 dirt-track racer), and why parallel twins used on dirt are typically set up with a 270-degree crank instead of the traditional 360. Apparently the irregular power pulses allow the rear tire to hook up better.
--mark
'20 Triumph Tiger 900 Rally Pro / '19 Triumph Scrambler 1200 XE / '11 Triumph Tiger 800 XC / '01 Triumph Bonneville cafe
My ride reports: Missile silos, Labrador, twisties, and more
Bennington Triumph Bash, Oct 1-3, 2021
people will laugh at you if you keep talking about that buell.
Cliff's Cycles KTM
NETRA enduro B-vet
Close your eyes, look deep in your soul, step outside yourself and let your mind go.
hahaha You guys should try a buell 1125r some times, no bike like it!
If you want to compare numbers, i dont care about horse power because it is a direct function of torque and rpms. I dont care about peak torque either, for me its about the most widely used amount of torque available. I'm not a highway racer, riding at max rpms arnt my game, back roads and twistiest are.
the new bmw s1000rr seems to have an interesting torque curve as well, seems like it would be a lot of fun.
so, i'd have to say, i've rode a 600 and 1000 before. . . they are balls to the wall when you open them up. But, for general everyday riding (i ride about 10 months out of the year) i prefer my buell (until i can get my hands on a bmw f800gs).
Nivek
"if you arn't riding like your on rails, then your sight seeing"
You should get an RC51 and call it a day.
i researched the RC51, i've heard peoples reviews as they made the switch to buell.
but hey, everyone is looking for something slightly different.
Nivek
"if you arn't riding like your on rails, then your sight seeing"
Last edited by csmutty; 02-17-10 at 12:34 PM.
-Christian LRRS/CCS HasBeen ECK Racing
2011 Pit Bike Race CHAMPION!
that zrx looks like it would be a hell of a ride, just depends on the characteristics of the bike that engine is in.
i once read somewhere that some of the toughest racing is gp125s the amount of talent it takes to be consistently fast, not to mention on some tight twistie roads, it would probably be hard to keep up with such a light bike.
as i said there are a lot of great bikes, my only complaint is i'll need a large stall for all the different bikes i would like to ride
Nivek
"if you arn't riding like your on rails, then your sight seeing"