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madandy
5th February 2004, 16:39
My 400 buzzes along at 6000rpm in 6th at 100km/h...To me this seems a bit high...I dont know if its been geared down I hardly ever need to shift down to overtake and can leave it in top round town at 50-60km/h...seems a waste of a 6 speed cog box...what do you all reckon?

Hitcher
5th February 2004, 16:58
A 400 is still a smallish engine. Where's your redline on that thing? That will give you a steer. My 250 runs at 6500rpm at 100kmh in top, whereas my 1200 runs at 3500. The 250 is redlined at 14,500 and the 1200 at 10,500.

mangell6
5th February 2004, 17:29
On the FZ1 I travel at 100kmh in fourth at 5,000rpm, I find that being in sixth at 4200rpm I get too much chain snatch and find that the higher revs are quite good. My redline is at 11500 or there abouts and have recentely been travelling in third gear at 5500. I have found this to be quite a combination as it allows me to roll on from about 4500rpm.

As the bike can do 120km/h in first gear, 160km/h in second I should ask the dealer for a refund on the fifth and sixth gears.

Kwaka-Kid
5th February 2004, 17:33
ZXR400H did 6,000rpm for 100kmph, with a 14,500 redline. the 88 VFR400 NC24 does 6,500rpm for 100kmph with a 14,000 redline, and yes i first thought it was a tad high, but now i dont think about it, oh and i checked both bikes and they have stock gearing... my power only just comes to the feel at 7,000or just over, so unfortunatly sitting @ exactly 100kmph is like in the middle of a flat spot.

madandy
5th February 2004, 18:06
Red-line is 12500rpm...power comes on about 7500rpm...so I spose its just sitting there a tad off cam waiting to be unleashed into the lower gears...It gives around 260kms on $15 96RON , got over 300k's once, draining her right down to near empty, took 16.5L to fill...

Motu
5th February 2004, 18:17
Yes,you are close to it - max torque is the important point of your power curve,that's where you feel the kick.My 750 has max torque at 5500rpm,that's 120kph,and that's where it's happy.The engine is most economical at this point and will hold it with minimum throttle.I will think you will find most bikes are set to about this - made for countries with different speed limits.

wkid_one
5th February 2004, 20:38
ZXR400H did 6,000rpm for 100kmph.
Is this a new speed measurement I don't know about....100 kilometre miles per hour.....that must be quick.....no wonder he is doing well on the race track - he is measuring himself in imperial units still.......

I have a question on this tho??

Why do we call a tyre a 190mm profile - yet a 17inch rim??? Why haven't rim sizes moved across to metric??? Why don't we call them 180/425 Tyres? hey now why is that....

Shit even our libraries are across to the Dewie Decimal System - but those Wheel Manus refuse to move across.

I don't know why I typed this - it just popped in to my head

Andrew
5th February 2004, 20:43
mine red lines at 19000 revs!!

wkid_one
5th February 2004, 20:46
mine red lines at 19000 revs!!
Jesus - is your bike made by Bernina or Moulinex? I would have changed gear twice on the VTR by the time you hit 2nd

MikeL
5th February 2004, 21:05
mine red lines at 19000 revs!!

Yes, and I've heard it at 19000 rpm in neutral, Andrew, and it's not a sound that you wan't to keep hearing for long...

When I saw the redline on my Honda 400 was 13500 I thought that was a bit on the high side, but compared to yours it's nothing.

At 100 kph mine is doing exactly 7000 rpm in 6th and that's where the power starts to come on, so overtaking is a breeze without the need to change down.

The GSX1200 on the other hand just deoesn't seem to be comfortable at 100 kph in top gear which is about 3700 rpm even though it has loads of torque, so I actually find myself changing down more often on the 1200 than on the 400.

Kwaka-Kid
5th February 2004, 21:29
yeah andrew ive heard it too.. eshk, hey dude just a quick tip, maybe dont free-rev your engine so much like that, and your valve guide seals might last a bit longer, at the rate the poor thing is deterriorating youll be putting a gallon of oil in a week... revv's low dude.. on my 400 i wont exceed 5,000rpm within 3km, and 6,500rpm within 5km, after that i will flex it out a few times to like 7-8 then 9-10ish, and once im convinced shes warm and acting right, ill start going near redline in tight twisties, but then on the straights i will flick it up like 3 gears at a time to reach 6th and let her idle back down to like 4-6,000rpm. maybe im overly-cautious on my engines, but ive done this to them all, and this ones mint, had it since 16,000km, now done 28,000km in 4months, and i change the oil religiously @ 3,000km...comes out almost as clean as it goes in (pretty close) and always putoline DX4 motorcycle oil... and it has not ever given me trouble at all, no smoke, and has the same feel it did the day i bought it...in saying how careful i am with the revv's it counts the same with how much throttle i give it under 5,000rpm too, i wont just bog her down and put full load against the poor rings as its hurting her cold just as much as building the revvs gradually (right?)... so yeah, and no labouring of the engine too! i also make a ponit to take the flattest way out form my place etc... do others do this? maybe i should start a new thread.. sorry to go off on such a rampage..hehe

Andrew
5th February 2004, 21:32
yeah andrew ive heard it too.. eshk, hey dude just a quick tip, maybe dont free-rev your engine so much like that, and your valve guide seals might last a bit longer, at the rate the poor thing is deterriorating youll be putting a gallon of oil in a week... revv's low dude.. on my 400 i wont exceed 5,000rpm within 3km, and 6,500rpm within 5km, after that i will flex it out a few times to like 7-8 then 9-10ish, and once im convinced shes warm and acting right, ill start going near redline in tight twisties, but then on the straights i will flick it up like 3 gears at a time to reach 6th and let her idle back down to like 4-6,000rpm. maybe im overly-cautious on my engines, but ive done this to them all, and this ones mint, had it since 16,000km, now done 28,000km in 4months, and i change the oil religiously @ 3,000km...comes out almost as clean as it goes in (pretty close) and always putoline DX4 motorcycle oil... and it has not ever given me trouble at all, no smoke, and has the same feel it did the day i bought it...in saying how careful i am with the revv's it counts the same with how much throttle i give it under 5,000rpm too, i wont just bog her down and put full load against the poor rings as its hurting her cold just as much as building the revvs gradually (right?)... so yeah, and no labouring of the engine too! i also make a ponit to take the flattest way out form my place etc... do others do this? maybe i should start a new thread.. sorry to go off on such a rampage..hehe

Thats alright I'll smack you into line if I feel you're rambling on too much! :calm:

Motu
5th February 2004, 21:46
I have a question on this tho??

Why do we call a tyre a 190mm profile - yet a 17inch rim??? Why haven't rim sizes moved across to metric??? Why don't we call them 180/425 Tyres? hey now why is that....

Shit even our libraries are across to the Dewie Decimal System - but those Wheel Manus refuse to move across.

I don't know why I typed this - it just popped in to my head

You just answered your own question - yes,it's a 180/425,but we call it an inch number just to make it clearer.Of course the French have used true metric tyre sizes,on the Light 15,DS19 and stuff.They didn't change the world to their way luckly.A lot of things haven't changed to metric,we just call them metric sizes - like chains...good old imperial still - 520 is 1/2 x 1/4...so that's 5 for the 1/2 inch 20 is 2 eigths.So is 25 two and one half eigths? so is a 540 the same as a 550? who needs to know that crap,not me!

Slingshot
5th February 2004, 22:18
mine red lines at 19000 revs!!

At these kinda revs can you imagine a piston breaking free, punching through the tank and smacking you in the chin :no:

My bike red lines at 18500 revs, when you think about what that actually means it's quite amazing.
A piston probably smaller than a shot glass changing direction 37000 every minute (616 times every second) :gob: .

Kwaka-Kid
6th February 2004, 00:54
and where is the most load on a single part of an engine? conrod? no? i dont know.. guessing though, i vagually remember an alcohol influenced conversation with a bunch of rally dudes who apparently worked it all out and i think they said conrod? bottom connecting end of it.. maybe.. the alcomohol bit explains the poor memory, and possibly incorrect info :D

merv
6th February 2004, 06:48
...I dont know if its been geared down ..what do you all reckon?

Just count the teeth on your front and back sprockets and compare them to what they are meant to be stock. Have you got a owners handbook to look that up? It would be unlikely that any changes have been made to gearing inside the engine cases so sprockets are the best check.

6,000rpm at 100km/hr though sounds about what I'd expect for a 400 and this is backed up by the comments posted so far.

VFR750 does 4,500rpm at 100km/hr with 11,500rpm redline.

My DR250R doesn't have a tacho but doing the calc on the gearing it would be doing about 6,250rpm at 100km/hr on stock gearing, but then it doesn't have the rev ceiling that a small four does and would top out around 9,000rpm I would expect. That's single cylinders for ya.

georgedubyabush
6th February 2004, 08:54
At these kinda revs can you imagine a piston breaking free, punching through the tank and smacking you in the chin :no:

My bike red lines at 18500 revs, when you think about what that actually means it's quite amazing.
A piston probably smaller than a shot glass changing direction 37000 every minute (616 times every second) :gob: .

Isnt it all about piston speed?
The reason why the 250s do up to 19000rpm is because the piston isn't travelling very far, so the actual piston speed is comparable to bigger bikes and not really so amazing.
The tiny valves must move pretty quick though.

Kwaka-Kid
6th February 2004, 09:45
yep, i think so george, and how big/heavy the piston is... i think of the mighty XR500 engine in my garage, with a stock redline @ 6,500. But because its worked up as a race engine it now redlines @ an approx 13,500rpm.... mmm imagine that.. big heavy 500 single revving out to what the modern 400x4's do! :D

gpercivl
6th February 2004, 11:17
yep, i think so george, and how big/heavy the piston is... i think of the mighty XR500 engine in my garage, with a stock redline @ 6,500. But because its worked up as a race engine it now redlines @ an approx 13,500rpm.... mmm imagine that.. big heavy 500 single revving out to what the modern 400x4's do! :D

Hey KK, you should whack that motor into your VFR frame and go out and kick some serious butt in F3...I had heaps of trouble staying in front of a relatively stock engined XR-650 super motard guy at Ruapuna :D

fpsware
6th February 2004, 13:15
My 400 buzzes along at 6000rpm in 6th at 100km/h...To me this seems a bit high...I dont know if its been geared down I hardly ever need to shift down to overtake and can leave it in top round town at 50-60km/h...seems a waste of a 6 speed cog box...what do you all reckon?
I just recently went from a Suzuki FXR 150 to a Kawasaki ZXR 400. When I first road it I thought my revs were TOO HIGH. Doing 100Km/hr at 6000 rpms seemed to rev too much (red lines at 14000). But after having it a couple of weeks now I feel very comfortable with it. I really don't think anything of it now.

If I want to pass something doing 100Km I just give it a little more gas, there is no need to change down. Its got more than enough grunt to pass. I can do things on this bike in 6th gear that I couldn't do on my FXR in 3rd gear.

madandy
6th February 2004, 18:40
OK now i'm happy to say you've all answered well and I agree that having the engine reving at 6Krpm is normal and quite sensible!Esp. hearing from other 400cc riders who rev similar.
It is good ,in a way, to be able to overtake easily in top with just a little twist. :yes:

Thanks a lot
Andy

MacD
6th February 2004, 19:45
There is some information about the RF400 on this RF site (http://www.suzuki-rf.de/) as well as some photos. Supposedly the RF400 has variable valve timing (something like Honda VTEC) so you may find there's a distinct jump in power at higher revs?

There is also a Yahoo RF Forum (http://autos.groups.yahoo.com/group/suzuki-rf/) which has some interesting threads from time to time although you need a Yahoo (email) account to join.

And for an impressively complete site of information on Suzuki bikes check out www.suzukicycles.org (http://www.suzukicycles.org/) . There's a guide to decoding VIN numbers in the FAQ section too.

And yes, I did spend a lot of time searching the web when I bought my RF900 ;)

Hitcher
7th February 2004, 12:45
Just count the teeth on your front and back sprockets and compare them to what they are meant to be stock. Have you got a owners handbook to look that up? It would be unlikely that any changes have been made to gearing inside the engine cases so sprockets are the best check.


The latest Motomail catalogue has an absolutely wizard table in it that tells you the numbers of teeth front and rear, numbers of links (and the cost) of your ride's bog-standard OEM setup. Saves getting all greasy and having to take your socks off to count teeth...

SPman
8th February 2004, 21:16
Having regeared from 16/39 to 16/43, 100 kph in 6th equates to....5102 rpm! (According to my gear ratio program)
With the original gearing it was 4630rpm

bungbung
9th February 2004, 08:27
6krpm @ 100km/h on my old GSX400X

Motoracer
11th February 2004, 18:36
I suppose this thread's probably gone stale by now... but I'd like to share the fact that my FZR400 revs at around 6800rpm (over 6500 anyway) at 100kmph with stock gearing making it the revviest 400 I've known.

Generally speaking I guess the weight, bore and stroke of your pistons are directly proportional to the revs you can achieve, whereas the number of pistons is inversely proportional to it (due to less weight & better inherent balance).

I've always thought gas turbine engines (like in the Y2k) should be the way to go as there are no reciprocating parts like pistons. Only problems with them are weight and length of the engines..

slob
11th February 2004, 18:39
Whoops! That last post was by me, but my browser automatically logged me in as Motoracer...(he's my brother) :confused2

merv
11th February 2004, 18:43
I've always thought gas turbine engines (like in the Y2k) should be the way to go as there are no reciprocating parts like pistons. Only problems with them are weight and length of the engines..

Other problems (who remembers the Chrysler turbine car when it toured NZ?) are lack of throttle response - take a while to wind up and then they go, lack of engine braking - reverse thrust flaps needed or something like that eh!, lack of fuel economy and heat - they may have fixed those two in newer designs.

They were great when they tried them in Indianapolis cars but then that was long distance flat out racing with little need to vary the speed rapidly so I doubt they would ever have been any use on a twisty F1 circuit.