View Full Version : Thoroughly disappointed with a CBR600RR
ThEGr33k
22-11-08, 11:19 PM
its just a pleasure thing for me, i do about 4k per year.
Aye. Which is fair enough :D I cant imagine a ss600 being a great everyday bike or tourer. I mean of course it could do it. :cool:
Aye. Which is fair enough :D I cant imagine a ss600 being a great everyday bike or tourer. I mean of course it could do it. :cool:
I've done numerous trips to the continent on 750s (ZX7R/GSXR750) and an SV and they all made perfectly competent tourers. I can't see a decent 600 being any less capable in the role.
Hell, if I can do a camping trip on an RGV then anything's possible!
kwak zzr
22-11-08, 11:30 PM
ive done 300 mile trips 2 up with ease, my pillion said it was comfy'r than my v twin, it seems to do everything well but i really need to ride it more to confirm this.
ive done 300 mile trips 2 up with ease, my pillion said it was comfy'r than my v twin
There's the rub. The SV thou and VTR Firestorm are litre twins. So's the SP2 and 1098. Other than the engine layout, they're poles apart and only one of history's great masochists would go touring on an SP2!
ThEGr33k
22-11-08, 11:39 PM
There's the rub. The SV thou and VTR Firestorm are litre twins. So's the SP2 and 1098. Other than the engine layout, they're poles apart and only one of history's great masochists would go touring on an SP2!
Aye that's true LOL
wyrdness
22-11-08, 11:50 PM
I thought about a Daytona but crossed them off my list on aesthetic grounds. They ming badly.
The early curvy ones were beautiful. It's the later, pointier ones where they messed up the styling. Kind of like the opposite of the SV :D
The early curvy ones were beautiful. It's the later, pointier ones where they messed up the styling. Kind of like the opposite of the SV :D
It's the back end of the Daytona that mings, always did. All the pointy stuff happened at the front.
I was reading an old copy of PB yesterday while having a tyre fitted and stumbled across a mock-up of a (fantasy) ZX8-R:
http://1.bp.blogspot.com/_Mvhjidbvdzc/SLqkevWSd1I/AAAAAAAAHa0/P9-a0YoQDzU/s400/zx-8r.jpg
Now that, my friends, is ****ing gorgeous and I'd buy one in an instant.
yorkie_chris
23-11-08, 02:07 PM
To be fair, if I was looking for a litre twin, it wouldn't be an SV. It's never really had a reputation as being anything but watered down.
Been described as "an excellent first litre bike", dunno about anyone else, but when I see that it just makes me think "what's the point of having one then?"
The thing about litre twins is that they're roughly comparable with 750 fours. So not really an introduction to a "litre bike" at all.
The thing about litre twins is that they're roughly comparable with 750 fours. So not really an introduction to a "litre bike" at all.
Litre V-twins are poles apart from 750 IL4s in the way they feel and deliver their power.
plowsie
23-11-08, 04:25 PM
-want a bit of both?=street triple
:winner:
Sid Squid
23-11-08, 07:22 PM
No they're not, all UJMs.
No, they most emphatically are not.
You're twenty years too late, at least ;)
yorkie_chris
23-11-08, 10:03 PM
No, they most emphatically are not.
You're twenty years too late, at least ;)
Yeah, so. 20 years too late or not they're still all from japan and still all roughly the same. The term still works :-P
plowsie
23-11-08, 10:59 PM
I shall be off tomorrow to Honda to book my test ride on the Hanspree 600-RR's they have. I will be confirming whether or not it is a much better bike than my CBR600F and my SV.
I can probably tell you straight away that they won't be the bike for me. I'm probably too big. But I'm willing to give it a chance.
How did I miss this thread?
The problem here is trying to compare these two bikes which are different beasts!
I loved my SV and never wanted to get rid of it, but would I have it back in place of the RR - erm no. However I would love an SV too if I could afford one, mainly for the commute which I do daily.
What do I miss about the SV? Mainly the noise, the engine breaking and the low down torque. I loved the way the SV sounded baffle in or out and I really used the engine breaking too.
The RR does have a great, silent but ferocious noise and the engine breaking is fine, just not as severe as the SV.
Both bikes look great, but the RR (to me) makes me feel part of the bike and hurts my arms less despite the out and out sports position. It has really improved my driving too being so light and flickable, just need to build up some confidence.
You do have to rev the honda more as it's an IL4, but once you are used to it, you drive everywhere at 7k, so just a little touch and bang you're off!
I genuinely think it does everything I ask of it well, mind you so did the SV.
The SV made me smile the RR makes me grin!
Dangerous Dave
24-11-08, 07:45 PM
The problem here is trying to compare these two bikes which are different beasts!
Aye, you wouldn't compare an Aston with a Skoda and think they would be in the same class.
Aye, you wouldn't compare an Aston with a Skoda and think they would be in the same class.
yeah skoda's miles better:);)
ThEGr33k
24-11-08, 09:27 PM
Litre V-twins are poles apart from 750 IL4s in the way they feel and deliver their power.
Expand on this. Im interested to hear your experience :cool:
kwak zzr
24-11-08, 09:54 PM
i remember going from il4's (1998 cbr600) to the sv650s in 2004, ive been riding about 15 years but i found a vast change in riding style, i remember racing a golf gti and loosing miserably:( i was riding the sv on revs! twins are ridden low down on the revs but the bikes id been used to was just getting started at 9,000rpm.
I'm having the reverse now going from 4 years of v twins back to a screaming il4, my gixer sounds like its being thrashed at 5k but the power ain't even started yet.
KnightRider
24-11-08, 10:23 PM
Power and engine braking are there, you just didnt find them. You can't ride an SS600 like the SV you have to use the gearbox and keep the revs up.
Sounds like you want to try a Litre Twin or maybe an Bigger capacity IL4 like a 750 GSXR or a Litre IL4...
Or learn to re-adjust your riding style, it took me a little while to get used to my GSXR, but once you do, IMHO it much more rewarding to ride than the SV is.
Agreed - you need to spend a decent amount of time on a il4 before you get used to it. All the power and control in the engine is above 7000rpm. In terms of gears, 2nd or 3rd are fine around town and then when you get on the twisties 3rd, 4th and 5th come into their own.
I had the luxury of having the 07rr for 3 months whilst my SV was being repaired. It took some getting used to but when I got back on the SV I couldn't stand it. Whilst the SV is a great bike the suspension is not great, the brakes dont give much feedback and the bike is very top heavy. The CBR has about the same power low down as the SV but when you get into the high rpm is takes off.
Long story short - I bought one so I guess I am bias.
The Daytona comes up trumps on the sound but falls flat on its face on the looks.
I guess you're referring to a 955? Don't forget that you are not comparing apples with apples - the design is old.
If they'd only put a proper engine in the 675 I'd be more than tempted, but they don't, so I'm not.
Oh? How is it not 'a proper engine'? I own one BTW...
ThEGr33k
24-11-08, 11:39 PM
Oh? How is it not 'a proper engine'? I own one BTW...
I think he means a 1050 mad thing. :rolleyes:
I guess you're referring to a 955? Don't forget that you are not comparing apples with apples - the design is old.
In the context of a conversation about the 955i, yes, by Daytona I was referring to the same 955i as everyone else. The 675 is a lovely looking bike (if a bit spindly) but...
Oh? How is it not 'a proper engine'? I own one BTW...
...for a manufacturer's top-end sports bike, a third of its engine appears to be missing.
I guess Triumph no longer have the cojones to make a full power sportsbike. Shame.
ukgooner
25-11-08, 07:30 AM
I guess Triumph no longer have the cojones to make a full power sportsbike. Shame.
More like good business sense, why go up against the big 4 Japanese manufacturers when you have a nice niche market already?
Tim in Belgium
25-11-08, 07:37 AM
I think what Ogden may be trying to say is that they son't do a full fat litre class sports bike (niche or otherwise), I agree that the 675 is an able competitor in the SS600 class.
I was at Donington for the last round of BSB a few years ago when the Triumphs did their last race in the 600 class before the capacity hike to 650.
The 675 is a cheating competitor in the SS600 class.
Dangerous Dave
25-11-08, 08:00 AM
The 675 is a cheating competitor in the SS600 class.
Why would you think that, the balance is great between a 675 and a SS600 on track. What the 675 offers is different advantages, but it also loses out on top end drive and power when compared to the SS600's in the WSS and BSS paddock.
I have no complaints...
...but then I'm easy to please.
Sid Squid
25-11-08, 08:35 AM
The 675 is a cheating competitor in the SS600 class.
Errr... How? We've had differential capacities in many racing classes dependant on engine configuration - this is no different.
Engine capacity is only part of the story, a triple will be slightly compromised viz piston/valve area next to a four.
DanAbnormal
25-11-08, 09:07 AM
Hahahah. Yeah the CBR600RR is so crap! :rolleyes:
Hahahah. Yeah the CBR600RR is so crap! :rolleyes:
It's a Honda. QED.
I'm off to sulk......on my Honda CBR600RR.
I'm off to sulk......on my Honda CBR600RR.
As sulks go, it'll be utterly competent yet somehow soulless and ultimately underwhelming.
Dangerous Dave
25-11-08, 09:55 AM
it'll be utterly competent yet somehow soulless and ultimately underwhelming.
How many Honda's have you ridden for more than 30 minutes to come up with the attitude that all Honda's are the same?
As sulks go, it'll be utterly competent yet somehow soulless and ultimately underwhelming.
Meh! Your opinion.
I love mine and think it is a ****ing scream. It's got plenty enough "character" for me. It'll lift it's front wheel under power, shake it's head, back into corners and corners like a biatch. The fact that you have to keep it on the boil only adds to the fun and involvement in my book.
How many Honda's have you ridden for more than 30 minutes to come up with the attitude that all Honda's are the same?
He's got a point. I had a CBR600F as a loan bike once and I thought it was pants when I first got it. After a week of riding it I thought is was a great little bike.
Also had a VFR800. It made me feel 50 when I chucked a leg over it. They have that stigma don't they......but what a cracking bike. Would shame sports bikes, handled brilliantly and even sounded good on standard pipes.
custard
25-11-08, 10:30 AM
i had a cbr600fi for 9months. thought it was the most boring thing i had ever ridden, sold it for another hornet which is probably one of the most engaging bikes i have ever ridden...
horses for courses?
DanAbnormal
25-11-08, 10:56 AM
I'm off to sulk......on my Honda CBR600RR.
I was being facecious, methinks whoever started this post rode it like a 90 year old infirm old woman. They are amazing bikes. Souless my ****. That's just a cliche that everyone uses against Honda as they do everything so bloody well. I have the de-tuned CBR600RR engine in my Hornet and let me tell you that is not slow or boring.
Lets face it, anyone complaining on an SV forum about a bike being boring is probably in the wrong place to start with.
DanAbnormal
25-11-08, 11:14 AM
Lets face it, anyone complaining on an SV forum about a bike being boring is probably in the wrong place to start with.
Hehhehe. Brilliant.
I'm also off to have a thouroughly nice time on my 07 reg CBR600RR..........
I only read the 1st 2 pages. I have ridden a fair few IL4's and personaly i dont like the way you have to rev the things to get anywhere, but its something that you would get used to. I resisted the lure of a triple for ages, as i wasnt really a triumph fan. However, i jumped on a new 1050 Tiger for a test ride, and now i see why a lot of people went the triple route a few years ago. The new 1050 engine is astonishing. It has the low down grunt of a twin, and the top end of a half decent 4. The onely other bike i rode thatwas like that was a GSX1400. With 1.4L its going to pull.
Try a 1050 triple, or the 675 street triple.
I only read the 1st 2 pages. I have ridden a fair few IL4's and personaly i dont like the way you have to rev the things to get anywhere
See, that's as daft as saying that all v-twins are endowed with massive amounts of low-down grunt or make perfect tourers.
I've also ridden a fair few inline fours and if you think you have to rev them all to get anywhere, you clearly haven't ridden any big ones! Try something like an early Bandit 1200 and you'll see the folly in this whole idea that inline fours are inherently gutless.
OK, so a highly-tuned peaky little 600 is going to need some revs to make power. I've got a V-twin in my garage that does absolutely nothing until 8k, not much until 10k and then runs out of steam at 11.5k. Hardly great big gobs of low-down torque.
To illustrate the point, an SV650 makes, what, about 50bhp at 7000 rpm? My GSXR750 is making about 70bhp at the same revs. It's just the SV runs out of steam at 70bhp 2000 rpm later, while the GSXR makes more like 120bhp 7000 rpm later. The only reason the midrange feels weak is in comparison to the blistering top end.
Fours, twins, they're just engine layouts. They don't fundamentally define the character of the bike or the way it has to be ridden.
600s are for girls, though.
gettin2dizzy
25-11-08, 11:46 AM
600s are for girls, though.
And 1000s for guys?
750s must be for those... in the middle ;)
And 1000s for guys?
750s must be for those... in the middle ;)
750s are for heroes. Buy one. Preferably mine, so I can replace it with a thou ;)
KnightRider
25-11-08, 11:50 AM
And 1000s for guys?
750s must be for those... in the middle ;)
Or for those who cant yet make up their mind which way they swing :D
See, that's as daft as saying that all v-twins are endowed with massive amounts of low-down grunt or make perfect tourers.
I've also ridden a fair few inline fours and if you think you have to rev them all to get anywhere, you clearly haven't ridden any big ones! Try something like an early Bandit 1200 and you'll see the folly in this whole idea that inline fours are inherently gutless.
OK, so a highly-tuned peaky little 600 is going to need some revs to make power. I've got a V-twin in my garage that does absolutely nothing until 8k, not much until 10k and then runs out of steam at 11.5k. Hardly great big gobs of low-down torque.
To illustrate the point, an SV650 makes, what, about 50bhp at 7000 rpm? My GSXR750 is making about 70bhp at the same revs. It's just the SV runs out of steam at 70bhp 2000 rpm later, while the GSXR makes more like 120bhp 7000 rpm later. The only reason the midrange feels weak is in comparison to the blistering top end.
Fours, twins, they're just engine layouts. They don't fundamentally define the character of the bike or the way it has to be ridden.
600s are for girls, though.I have ridden some big ones, but i was referencing the comparrison to a SS600 and its not about power, its about the tourque that makes it pull.
I have ridden some big ones, but i was referencing the comparrison to a SS600 and its not about power, its about the tourque that makes it pull.
Power and torque are just two ends of the same mathematical formula.
KnightRider
25-11-08, 11:59 AM
Power and torque are just two ends of the same mathematical formula.
Exactly - you could always change the gear ratio if you want more torque. It isnt as though you are going to be doing 150mph that often!!
Exactly - you could always change the gear ratio if you want more torque.
Maybe.
Here's the power and torque chart for my old ZX7R:
http://daifnet.pre.org/album/Bikes/slides/rejet.jpg
Other than the iffy fuelling, you can see the torque curve is actually fairly flat. Doesn't really matter where in the rev range you are, you're not going to find more or less torque by changing up or down. What you will find, by increasing the revs, is more power.
DanAbnormal
25-11-08, 12:49 PM
I have ridden some big ones, but i was referencing the comparrison to a SS600 and its not about power, its about the tourque that makes it pull.
But my Hornet can out accelerate an SV650 in every gear. I have to feather the throttle to stop it from wheelieing. I guess I have a girls bike though. :p
Ooh, I do love these willy waving threads. hehe.
KnightRider
25-11-08, 01:09 PM
But my Hornet can out accelerate an SV650 in every gear. I have to feather the throttle to stop it from wheelieing. I guess I have a girls bike though. :p
Ooh, I do love these willy waving threads. hehe.
Only if you dont mind looking like this.
http://media3.guzer.com/pictures/bike_wind_face.jpg
ThEGr33k
25-11-08, 05:35 PM
Power and torque are just two ends of the same mathematical formula.
Indeed, more torque = more power at less RPM. :cool:
Exactly - you could always change the gear ratio if you want more torque. It isnt as though you are going to be doing 150mph that often!!
No... Changing gear ratio's increases the Drive force. Not the Torque, well not the torque the engine pruduces anyway.
People compair V-two to IL4. Well the reason 750's IL4's and 1000cc V2's used to race is because they had comparable power outputs, infact the 750's often had more power than the V2's. The reason the V2 pulverised the IL4's on the track is because the twins were producing the torue so had a better spread of power making them easier to ride for many reasons.
The reason making WSB IL4's a 1000cc was a bad idea is because a 1000IL4 in the same state of tune as a 1000V2 would be making WAY more power. (Note these reasons also work for the 675!) This is down to many reasons but the main ones as far as I know are:-
1- Weight of components. The pistons in a 1000V2 are MASSIVE in comparison to a 1000cc IL4. They weigh a lot more and so cause more stress on the Crank and Con rods in the engine at similar revs. Because of this a high revving twin needs components that are much stronger and lighter to allow the engine to rev and the power be made.
2- Air/Fuel mix getting in and out of the cylinder. Basically as the piston surface increases (the bore) the Percentage of the cylinder head that can be used for valves decreases. So when you have a V2's total valve area vs a IL4's total valve area the IL4 smashes the V2 to pieces. There arnt many ways around this that isnt mad (oval pistons, which solves both problems but makes others... cost :(). Ducati's Desmodromiccam setup allows them to run the valves closer to the pistons because of the precision afforded by this setup and that is a reason they could compete in WSB with the 999.
So obviously to offset this capacitiy is used. With capacity comes Torque, with torque comes less revs to = same power and this solves both of the problems above. Hence the Ducati 1200's which are on a par with the IL4's on power now at a similar level of tune... cost of prodution. They dont have to make the 1200 rev much to make the same power. I think they create max power at 9750RPM. (Compair to below!!!).
When Ducati said their 999 was reaching F1 levels of tune they wernt talking rubish. I remember reading the 999 max power of 195-210BHP was at 14500RPM, and the engine could rev to over 15000RPM. To make a twin rev that high and still make the power (Get enough air & fuel into the pistons) and be reasonably reliable is amazing! :cool:
End of my geek attack. Basically it comes down to this... Do you want a big spread of power? 1000cc 2 cylinder, do you want a peaky engine that needs reving more to make the same progress then a 4 cylinder 600-750. If you want a mix of both then you want a 1000cc 3-4+ cylinder. Simple as that.
Which is best... well Vtwin of course :p
Which is best... well V4 of course :p
Post corrected.
ThEGr33k
25-11-08, 05:46 PM
Post corrected.
ha ha. TBH I almost agree. I like V4's... Its just on a sound basis it goes like this,
60*V-twin
90*V-twin
Other V-twin configs
90* V4 (180* crank)
other V-4
Single
IL3
IL4 (screamer... None screamers can be made to sound like any of the above. E.g. the new R1 sounds like a 90*V4 with a 180* crank! So should sound sweet, with Zorst).
Best sound bite i can get of the new R1 (http://uk.youtube.com/watch?v=GSsuqbmeQrY)... Get some Zorsts on that and itll be sweet like this (http://uk.youtube.com/watch?v=bXxkVhIXq7w&feature=related) and this (http://uk.youtube.com/watch?v=cKLjLWDaWP0&feature=related)In real life ofcourse itll sound even better.
I look forward to WSB this year as there will be soooo many sounds, Big twin, V4, IL4 screamer (nothing special :p) and IL4 odd firing, (new R1)
why's everybody on about speed with the sv it's not about that what other 600 v twins do you know of that you can buy for just over 4 grand NEW service yourself look nice simple to ride and thats still fun i have no illusions of grandeur about it so it's not the fastest or got the best suspension so what it's comfy and gutsy good mpg fun starts every morning thats more important to me.
Modern 750 IL4s have a peakier power delivery compared to litre V-Twins, which makes the V-Twin easier (lazier) to ride in most situations. Just about every IL4 750 I've ridden (mainly Gixers, but a couple of MVs as well) have felt a lot bulkier as well, making them a bit of a handful in traffic.
I've spent a good few hours riding stuff like 916, 966, 998s and for me the V-Twin is always the nicer to ride. I find that after a good thrash on a litre V-Twin I'm not as worn out as I am after riding a 750 IL4. The 750 seems to be more frantic and demanding to ride.
He's got a point. I had a CBR600F as a loan bike once and I thought it was pants when I first got it. After a week of riding it I thought is was a great little bike.
Quite. I'm waiting to meet Ogden on a trackday, so I can show him just how boring my CBR600 is as it passes him.
KnightRider
25-11-08, 09:13 PM
Quite. I'm waiting to meet Ogden on a trackday, so I can show him just how boring my CBR600 is as it passes him.
Can I book a ticket in the grand stand for that. Would pay big bucks for an ogden showdown.
kwak zzr
25-11-08, 09:20 PM
cbr is one hell of a track bike, mind you ive seen an sv650 on video on this site :) overtaking 1000cc il4s, its the rider not the bike.
Jelster
25-11-08, 10:56 PM
Where do you want me to start.....
( we've been here before havent we ;) :D )
Would you like a list ? I mean, I only kept mine 6 months......
If you want character (not starting, stalling when it feels like it, crap suspension) buy a Falco. If you prefer to not have all these things, buy a Honda.... I did and haven't looked back.
(well I did have a Gixer in between too)
.
Would you like a list ? I mean, I only kept mine 6 months......
If you want character (not starting, stalling when it feels like it, crap suspension) buy a Falco. If you prefer to not have all these things, buy a Honda.... I did and haven't looked back.
(well I did have a Gixer in between too)
.
:winner::winner:
Jelster
25-11-08, 11:02 PM
It's a Honda. QED.
So which bike has won the WSB Superbike title for the last (God knows how many) years ?
Did somebody with a Honda bully you when you were a kid or something ??
:o)
>
So which bike has won the WSB Superbike title for the last (God knows how many) years ?
Absolutely no idea. I haven't followed WSB in about a decade.
Jelster
25-11-08, 11:16 PM
Absolutely no idea. I haven't followed WSB in about a decade.
Ahh I see.... Since somebody with a Honda upset you maybe ?
.
It's true, it's true. I was fiddled with as a child by Baba-san.
buy a Honda.... I did and haven't looked back.
.
what he said x2
ThEGr33k
26-11-08, 12:06 AM
Only honda i had was a bucket of bolts... a 1984 VT250FD. Granted it was a good bike in its day though lol.
ThEGr33k
26-11-08, 12:12 AM
So which bike has won the WSB title for the last (God knows how many) years ?
Ducati? (http://www.f1network.net/main/s180/st45645.htm)
If you want character (not starting, stalling when it feels like it, crap suspension) buy a Falco. If you prefer to not have all these things, buy a Honda.... I did and haven't looked back.
.
Yours did that? How unfortunate. :( Oh well mines running very well (and has through 12,000 miles and 9 months) and the suspension has been sorted, penske and K-tech (well we shall see about K-tech, changing the springs and oil for something to suit me and not a 15stone individual so shall see what happens there) are my hero's :D
yorkie_chris
26-11-08, 12:46 AM
The 750 seems to be more frantic and demanding to ride.
For some, that's the appeal.
fizzwheel
26-11-08, 08:44 AM
For some, that's the appeal.
It is for me. I like riding in the frantic style, its what I learnt on and I find it satisfying to ride the bike in that way.
Sid Squid
26-11-08, 09:06 AM
Basically as the piston surface increases (the bore) the Percentage of the cylinder head that can be used for valves decreases.Errr.. No. It's the other way 'round - as the the bore increases there is more piston-valve area, thus greater potential valve area and a larger piston crown - more area for the gas pressure to act upon. This is why fours go better - they've got more of it.
So when you have a V2's total valve area vs a IL4's total valve area the IL4 smashes the V2 to pieces. There arnt many ways around this that isnt mad (oval pistons, which solves both problems but makes others... cost :(Oval pistons don't increase piston-valve area, a comparable round piston is better, and two is better than that, they were resurrected by Honda in an attempt to create a pseudo V8 in a racing formula that allows only four cylinders, (were used by Rudge in the 20s).
Ducati's Desmodromiccam setup allows them to run the valves closer to the pistons because of the precision afforded by this setup and that is a reason they could compete in WSB with the 999.Not any more, when first introduced desmo systems, (used by Mercedes in racing cars), allowed more radical valve timing when materials were the limiting factor otherwise.
So obviously to offset this capacitiy is used. With capacity comes Torque, with torque comes less revs to = same power and this solves both of the problems above. Hence the Ducati 1200's which are on a par with the IL4's on power now at a similar level of tune... cost of prodution. They dont have to make the 1200 rev much to make the same power. I think they create max power at 9750RPM. (Compair to below!!!).It's not about capacity directly, it's still piston-valve area which is the limiting factor, a smaller engine with the limited induction area, (typically twins, unless ultra oversquare in an attempt to get some piston-valve area back), would suffer even further due to lack of gas process abilities, overall capacity partly offsets this, but it's gas area that matters. 9750rpm to a twin shaped like a Ducati is an enormous piston speed, the stresses are vast.
I remember reading the 999 max power of 195-210BHP was at 14500RPM, and the engine could rev to over 15000RPM. To make a twin rev that high and still make the power (Get enough air & fuel into the pistons) and be reasonably reliable is amazing! :cool:It's not that hard, it just needs to be made of unobtanium and only required to last 200 miles before it's all scrap - this is bad engineering choices. And let's not forget how quickly Ducati abandoned twins when building a GP racer, the only reason they have persisted with twins on their road bikes is brand identity, just like Harley D they'd love to chuck it in and build modern designs without all the heritage baggage that weighs them down - but if it ain't a Vee-Twin it ain't a Duke/Harley/Guzzi etc etc.
End of my geek attack. Basically it comes down to this... Do you want a big spread of power? 1000cc 2 cylinder, do you want a peaky engine that needs reving more to make the same progress then a 4 cylinder 600-750. If you want a mix of both then you want a 1000cc 3-4+ cylinder. Simple as that.A spread of power comes from a longer stroke and smaller valve area - this spreads good VE across a wider range as gas speeds are higher, at the cost of overall gas flow and thus peak power, also the longer stroke simply means the handle is longer, the specific engine configuration isn't the overriding factor. Revs aren't the full story, peak piston speeds are important, a longer stroke, such as a twin typically would have - for a given capacity, limits the revs, if the piston physically has to travel farther it's speed will have to be higher rev for rev, against the, typically, shorter stroke of a four.
Which is best... well Vtwin of course :pAs much as I love the motor of my SV1000, and twins in general for that matter, these days they exist because we like them, not because they're 'good', they're poor engineering, my ten-year old ZX6 is superior and there's no getting away from it. Add to this the fact that I'm never going to get the fuel figures out of a twin I'll get from a four because in order to get any power from an inefficient design we abandon all other considerations and just chuck fuel at it. And I still can't understand why anyone cares what the revs are, low, medium, high -who cares? Numbers on a dial no more.
ThEGr33k
26-11-08, 11:27 AM
Errr.. No. It's the other way 'round - as the the bore increases there is more piston-valve area, thus greater potential valve area and a larger piston crown - more area for the gas pressure to act upon. This is why fours go better - they've got more of it.
http://www.visi.com/~moperfserv/ducati997.htm (http://www.visi.com/%7Emoperfserv/ducati997.htm) The bottom Paragraph is the interesting part. ;) As the bore goes up the valves can get bigger, but as a percentage of the bore taken by valves it gets lower :( Meaning as the bore increases the amount of air needed vs the amounts needed drops... Then throw into consideration that the Ducati has to fill a bigger volume through these valves. Though I think you have since you mention the 4 cylinder beats the V here.
Oval pistons don't increase piston-valve area, a comparable round piston is better, and two is better than that, they were resurrected by Honda in an attempt to create a pseudo V8 in a racing formula that allows only four cylinders, (were used by Rudge in the 20s).
But even so, 155 bhp at 15 000 rpm in a bike scaling only 158 kg with lights and a generator, practically in road-legal trim, guaranteed scintillating performance and seemed to bear out Fukui's insistence that what had begun as a means of circumventing a restrictive set of regulations, in fact turned out almost by accident to offer a significant improvement. The reason probably lies in an inherent limitation of poppet-valve engineering: a four-stroke engine is restricted in the power it can produce only by the amount of mixture you can pack into the cylinder, and the speed at which you can get rid of the unbumt exhaust gases after combustion; in other words, flow, which in turn is dictated by valve area. How big the overall valve size can be in turn depends on piston area, and therefore the bore.
Having oval pistons enables more valves to be used, in turn offering greater flow, less reciprocating weight, higher speeds and more power. The success of the NR project made it almost certain that an oval-piston road bike would be introduced by Honda before very long - most likely a 250 V-twin, maybe even a turbo! Its launch would give the ultimate justification for Fukui-san's perseverance with a project so many discounted so harshly.
Not any more, when first introduced desmo systems, (used by Mercedes in racing cars), allowed more radical valve timing when materials were the limiting factor otherwise.
So why do they use them in Motogp and attain amazing revs and power, even compaired to pnumatics? Yes back in the day when the springs sucked they would have had to turn to other tech just to attain the performance of a modern spring. However you look at it Desmo should be better than any other system.
It's not about capacity directly, it's still piston-valve area which is the limiting factor, a smaller engine with the limited induction area, (typically twins, unless ultra oversquare in an attempt to get some piston-valve area back), would suffer even further due to lack of gas process abilities, overall capacity partly offsets this, but it's gas area that matters. 9750rpm to a twin shaped like a Ducati is an enormous piston speed, the stresses are vast.
Yes its is very big speed. Another and I think more important reason they go for over square is to reduce the average piston speed and less to gain head space.
It's not that hard, it just needs to be made of unobtanium and only required to last 200 miles before it's all scrap - this is bad engineering choices. And let's not forget how quickly Ducati abandoned twins when building a GP racer, the only reason they have persisted with twins on their road bikes is brand identity, just like Harley D they'd love to chuck it in and build modern designs without all the heritage baggage that weighs them down - but if it ain't a Vee-Twin it ain't a Duke/Harley/Guzzi etc etc.
This unobtanium you mention costs a lot. If you can do it better I'd go talk to them! :D
A spread of power comes from a longer stroke and smaller valve area - this spreads good VE across a wider range as gas speeds are higher, at the cost of overall gas flow and thus peak power, also the longer stroke simply means the handle is longer, the specific engine configuration isn't the overriding factor. Revs aren't the full story, peak piston speeds are important, a longer stroke, such as a twin typically would have - for a given capacity, limits the revs, if the piston physically has to travel farther it's speed will have to be higher rev for rev, against the, typically, shorter stroke of a four.
Yes but when you get fewer bigger pistons Bore and stroke are a ballancing game, You want short stroke (less piston speed) but small pistons (again the percentage of head available for valve area) but obviously can have both unless you go for more cylinders... So for a V-twin you have to get as close to perfect as you can with both air flow and piston speed.
As much as I love the motor of my SV1000, and twins in general for that matter, these days they exist because we like them, not because they're 'good', they're poor engineering, my ten-year old ZX6 is superior and there's no getting away from it. Add to this the fact that I'm never going to get the fuel figures out of a twin I'll get from a four because in order to get any power from an inefficient design we abandon all other considerations and just chuck fuel at it. And I still can't understand why anyone cares what the revs are, low, medium, high -who cares? Numbers on a dial no more.
Well tbh this argument is pretty flawed. A 90* V shape engine is a better design than a IL... Its has better ballance and is more compact. The only slight down side is they can be a little heavier and have more internal parts and costs more because of this. This is off set quite happily by the advantages. If people are willing to spend the money. Unfortunatly as Honda found they are not.
V-twins arnt inherently bad at fuel consumption, Honda V-twins are for whatever reason. Mine, the lowest ive ever had is 42MPG which was better than the GSX1100, SV650 and Triumph speed four people got who I rode with at a very fast pace up in North yorkshire. Ive got 55mpg on a good run cruising at about 85.
I dont really talk about revs, its how flexable an engine is for me. IMO for the road for me the V-twins spread of power works better than a smaller capacity multi cylinder's and is less harsh and frankly OTT than a 1000cc multi cylinder.
But at the end of the day different people enjoy different things. I guess we should just enjoy what we do and get on with it. :p
DanAbnormal
26-11-08, 12:06 PM
Will you two get a room or something! :p
So why do they use them in Motogp and attain amazing revs and power, even compaired to pnumatics?
You could, in theory, run a pneumatic desmo-type valve control system. Not sure why anyone would bother though. Desmo valves do allow higher revs and improved flow because they allow the valves to open and close wider and faster. With a traditional sprung arrangement you have full control over the way the valve opens but not so much over how it closes. A desmo system allows full(ish) control over both. But I'm sure you already know this.
Yes its is very big speed. The reason they go for over square is to reduce the average piston speed not to gain head space. ;)
Trouble is, you can end up with huge pistons which, while they don't have to travel so fast, still carry a lot of inertia. There's a compromise and it's called more cylinders - hence why Honda tried to go the V8 route as mentioned earlier. You can, after all, have a long-stroke multi-cylinder engine if you really want to.[/quote]
ThEGr33k
26-11-08, 12:13 PM
You could, in theory, run a pneumatic desmo-type valve control system. Not sure why anyone would bother though. Desmo valves do allow higher revs and improved flow because they allow the valves to open and close wider and faster. With a traditional sprung arrangement you have full control over the way the valve opens but not so much over how it closes. A desmo system allows full(ish) control over both. But I'm sure you already know this.
Trouble is, you can end up with huge pistons which, while they don't have to travel so fast, still carry a lot of inertia. There's a compromise and it's called more cylinders - hence why Honda tried to go the V8 route as mentioned earlier. You can, after all, have a long-stroke multi-cylinder engine if you really want to.
Aye exactly what I was getting at :) But if you are set on the number of cylinders then its a compremise between bore and stroke :(
Wow I missed this thread somehow
ROFL
That is all :rolleyes:
Quiff Wichard
01-12-08, 03:26 AM
i am sorry i have to revive this..
cant sleep- hence 3.30am..
just read all of this thread with interest...
then got to the end..
I would suggest that if sid was your mum's mum then it is very advisable not to try and educate him on how to suck the oval objects that are produced by a chicken..:smt019
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