Over revvvv??? Think again!!!!

For a bike like Kawasaki ZXR250, the engineer design the engine to withstand pressure up to 19000rpm. We don't have to rev it there though since the peak power arrive at 16000rpm. What we can do is safely down shift a number of gear while approaching a corner at high speed and at 16000rpm, knowing that we have another extra 3000rpm to play with, right??
But what happen if we decide to rev its tits out >>>> This happen to a friend's bike after he lends his bike to someone else...
The piston, before:


The piston, after,, auwwchhh!!


Cylinder head & valve before:


Cylinder head & valve after:


Think about it, at 19000rpm the engine spin at more than 300 times per second. The piston crash into the exhaust valve before the valve gets enough time to close properly.

can i say, this only happen to high-revvin bike such as zxr250, cbr250 and gsxr250 ?

as i know, only those bike have very2 high RPM (19k).

Aiyoo! Zul!!!! You're trying hard not to insult the ZXR250 by mentioning CBR250 and GSXR250 name there right???

It usually happen when U get over excited with a high rev engine, but it can also happens to a high powered engine.
May I ask, why do we have a rev limiter an a high perfomance engine? Remove the rev limiter an a CBR1000RR and try revvin it into the redline. The same thing might happen and do U mind, the CBR1000RR doesn't have a 19K rpm redline.

U may ask why this seldom happens to a CUB's engine.
Engine like those used in a CUB has been design to withstand full throttle blast even in neutral. Its designed for economy, not performance.
Wanna proof. A 4 stroke 125cc engine produce around +-10-12 hp. ZXR's 250cc engine produce around 40-45 hp. The ZXR has 2 times the cc but the engine produce 4 times more power.
Hmmm,

art zxr wrote:Aiyoo! Zul!!!! You're trying hard not to insult the ZXR250 by mentioning CBR250 and GSXR250 name there right???

honestly, i'm not intended to insult any bike. every bike got their pros and cons. i'm clear with that.

ok, why the 250cc 4-cylinder inline bikes designed to have such massive 19k RPM? why not the 1k litre bikes?

p/s - is there any chance to fit the rev limiter to your bike bro? if the answer yes, how its going to be fitted.

thanks.

errr kene speaking ker...errr for me any bike is the same..they all have the specific optimum rev...switch gear too early u got less power and switch too late u got wasted power n gasoline n the chances of getting 'bobos' piston and 'pocket' aint that right abg art

Oii Scid apa ko merepek daa

Efficiency la Zul......
Actually, the smaller the engine, the faster it can spin. The tiny engine in the remote control car can spin at more than 30Krpm. The big engine in the big ship and train redlines at +-1500 rpm. They cruise at 750rpm, how bout that??? Understand? The 1litre engine designed so they redlines at their most efficient rpm range.

I,m sure U don't want a small engine in a remote control car to spin up to 10Krpm only right? That'll be too slow.
Another thing, can U imagine the big engine in a ship spin at 10Krpm . With each piston the size of a big van it can be catastrophic.

Simply, U can cruise safely at 12K rpm on a ZXR250. Even more than that. They redlines at 19K rpm because they can do it, but never push the limits.

aku x kira.....
aku nak jugak guna bahasa melayu......
malas kira......

art zxr wrote:Oii Scid apa ko merepek daa

Efficiency la Zul......
Actually, the smaller the engine, the faster it can spin. The tiny engine in the remote control car can spin at more than 30Krpm. The big engine in the big ship and train redlines at +-1500 rpm. They cruise at 750rpm, how bout that??? Understand? The 1litre engine designed so they redlines at their most efficient rpm range.

I,m sure U don't want a small engine in a remote control car to spin up to 10Krpm only right? That'll be too slow.
Another thing, can U imagine the big engine in a ship spin at 10Krpm . With each piston the size of a big van it can be catastrophic.

Simply, U can cruise safely at 12K rpm on a ZXR250. Even more than that. They redlines at 19K rpm because they can do it, but never push the limits.

ok, i got the main point there!

high performance bike with big cc's will have lower RPM limits than high performance bike with smaller cc's as both type of bikes getting its peak power at different RPM.

some cases that happen to ZXR250 (i mention it coz its only the famous 250cc's bike here! ) is because their owner are not well-kept their bike and do know nothing about maintenance of the high revving bike and the scariest part is they push the bike out of the limit because they even know nothing about the limit! aiyaa.. dgr bunyik zxr250 oren kat dlm terowong nak pergi ZZ sup semalam... pehhh

p/s- i might be consider to own a ZXR250. probably its malaysian bike, hassle free maaah.

assasins wrote:aku x kira.....
aku nak jugak guna bahasa melayu......
malas kira......

base melayu la....

matnan wrote:

assasins wrote:aku x kira.....
aku nak jugak guna bahasa melayu......
malas kira......

base melayu la....

apa ko merapek ni matnan?

Ooo!! Matnan maksudkan bahasa=base, buaya=boye, harimau=rimau, kerbau=kebau, mmm...
Entah, Matnan boring kot kat DTBS ni sunyi jekk...
Letak iklan sikit, haritu masa gi wedding kat melaka dapat kenal dgn seseorang ni, mmmm cantik kan??
Zul mesti jeles punya pasni nak report yg Abg Art ni nakal

art zxr wrote:Ooo!! Matnan maksudkan bahasa=base, buaya=boye, harimau=rimau, kerbau=kebau, mmm...
Entah, Matnan boring kot kat DTBS ni sunyi jekk...
Letak iklan sikit, haritu masa gi wedding kat melaka dapat kenal dgn seseorang ni, mmmm cantik kan??
Zul mesti jeles punya pasni nak report yg Abg Art ni nakal

bahasa engineer kan lain sikit...
bunyi lain tapi makna sama...

macam sepak(guna kaki) n sepak(guna tangan)...

tu gambo abg art dgn sape tuh?

matnan wrote:tu gambo abg art dgn sape tuh?

berkenan ker matnan?

Alaa Matnan, bunga bukan sekuntum, ramai laaa,

art zxr wrote:Alaa Matnan, bunga bukan sekuntum, ramai laaa,

matnan bukan kuntum bunga jer,tapi sekali pasu2 dier cabut...

art zxr wrote:Ooo!! Matnan maksudkan bahasa=base, buaya=boye, harimau=rimau, kerbau=kebau, mmm...
Entah, Matnan boring kot kat DTBS ni sunyi jekk...
Letak iklan sikit, haritu masa gi wedding kat melaka dapat kenal dgn seseorang ni, mmmm cantik kan??
Zul mesti jeles punya pasni nak report yg Abg Art ni nakal

kak ida da tau lom ni...kak idaaa oooooooo kak idaaaaaa.....