shane661
Needs a life
Posts: 11494
|
posted November 07, 2006 02:29 PM
Anyone Experience Broken Valves?
I have heard of a few guys on here snapping valves off. I was just wondering...if this happend to you:
What cams, springs, and valves were you running? Running N20? Under what conditions did it fail?
  
|
kawpower
Zone Head
Mr kawasaki 2 you!
Posts: 887
|
posted November 07, 2006 03:25 PM
which bikes are u talking about, ?
|
shane661
Needs a life
Posts: 11494
|
posted November 07, 2006 03:37 PM
ZX-12R.
|
Texas12R
Zone Head
Posts: 545
|
posted November 10, 2006 05:16 AM
I have been told by a mechanic that the first weak link youll find are the valve springs.
my original question was along the lines of increasing the rev limit and what he thought about that relative to failure.
I wonder if the zx10 has the same spring? I have seen the post that the cams are the same.
but the zx10 rev limit is considerably higher.
|
ninja12
Needs a job
Posts: 3310
|
posted November 10, 2006 10:51 AM
Cams size is only one factor, others to consider are valve weight, stem size, construction material and spring pressure. These can change the safe rev limit over time.
|
NOS1290
Expert Class
Posts: 103
|
posted November 10, 2006 11:07 AM
Two years ago I melted an exhaust valve head off at Maxton. I was running a 60 shot of NOS on stock cam, stock rev limit, and 55 lbs of spring pressure. Motor was totally destroyed. valve through piston, cracked block, cracked crank, bent rod, cracked head, bent cams. Bad. Very Bad.
I now run big cams, stainless exhaust valves,, and extended ECU, and 65 lbs of spring pressure with no problems yet (knock on wood).
|
shane661
Needs a life
Posts: 11494
|
posted November 10, 2006 02:08 PM
Was that stock pistons that you were running with the 60 shot?
|
NOS1290
Expert Class
Posts: 103
|
posted November 13, 2006 12:54 PM
Pistons were Muzzy 1270 pistons. I have 3 I'll sell for cheap!
|
shane661
Needs a life
Posts: 11494
|
posted November 13, 2006 01:02 PM
The mixture must have leaned out pretty bad...any idea of what happened to cause that?
|
NOS1290
Expert Class
Posts: 103
|
posted November 13, 2006 02:00 PM
Stock exhaust valves "may" actually be 2 piece. I think the valve just overheated, but the motor didn't necessarily lean out. A/F was 12.9:1 just before she let go. I suppose 1 injector could have leaned out, but I don't think so.
|
shiphteey
Needs a job
Posts: 2529
|
posted November 16, 2006 04:32 PM
Mind if I ask what type of fuel upgrades you did to run a 60 shot?
What gears where you spraying @ Maxton?
And what MPH did you peak out (best run)?
I am thinking about spraying 60 on the stock motor w/timing taken out, rich, cold plugs and a prayer!
A.
|
shiphteey
Needs a job
Posts: 2529
|
posted November 16, 2006 04:33 PM
Mind if I ask what type of fuel upgrades you did to run a 60 shot?
What gears where you spraying @ Maxton?
And what MPH did you peak out (best run)?
I am thinking about spraying 60 on the stock motor w/timing taken out, rich, cold plugs, and an additional fuel pump since I am about maxed out @ 215 RWHP w/the 40 shot (a1 model) before one factors in the effects of ram air.
A.
A.
|
NOS1290
Expert Class
Posts: 103
|
posted November 17, 2006 09:59 AM
I tried helping you once at Maxton. You borrowed a bunch of tools, and never returned them. left them all over the place. Broke half my drills. That was the same weekend you shut the course down for over an hour while people chased you down a live runway.
|
Megabyte
Pro
Posts: 1047
|
posted November 17, 2006 10:57 AM
quote:
Two years ago I melted an exhaust valve head off at Maxton. I was running a 60 shot of NOS on stock cam, stock rev limit, and 55 lbs of spring pressure. Motor was totally destroyed. valve through piston, cracked block, cracked crank, bent rod, cracked head, bent cams. Bad. Very Bad.
I now run big cams, stainless exhaust valves,, and extended ECU, and 65 lbs of spring pressure with no problems yet (knock on wood).
What Cams are you running?
____________
We First make our habits and then our habits make us.
|
TRNorBRN6001
Needs a job
Posts: 2021
|
posted November 17, 2006 12:38 PM
Ouch!!!!!!!, I have done some stupid stuff myself, so i will not make to many comments......................But I'll wager that other live runway at Maxton was a
touch smoother and more to his likeing!!!!!!!!
Back on subject:
Had a stock exhaust valve go on on a stock bike at the mile, came apart just a little above the valve at the stem. I had a little 70 shot, but was not near the limiter.
____________
TFA 200MPH CLUB MEMBER!
|
shane661
Needs a life
Posts: 11494
|
posted November 17, 2006 03:35 PM
Sounds like this isn't such an uncommon occurance. I was thinking of stainless valves and ti retainers. What is the best out there?
|
shiphteey
Needs a job
Posts: 2529
|
posted November 17, 2006 10:27 PM
 Edited By: shiphteey on 17 Nov 2006 22:35
I tried helping you once at Maxton. You borrowed a bunch of tools, and never returned them. left them all over the place. Broke half my drills. That was the same weekend you shut the course down for over an hour while people chased you down a live runway.
---WOW. What a loaded statement. Well, let me first thank you (again?) for letting me borrow your tools. I remember you, sorry, don't remember your name but you had the Jeep and the Green 12, datalogging. If you would have said 14 months ago (instead of claiming 2 years ago just from this post I would/could have figured out it was you since I remember this happening to you and could have followed up with you, most likely thanking you for your help as I have others like Dave O and V. Hill) My 1st trip to Maxton as well as first time using nitrous was quite an eye opening experience, I was pretty disorganised and being a rookie, I made a mistake. I've explained that, got reamed for it, apologized to the community about it, never happened again, and even made sure to let friends to are going to Maxton as first timers know not to miss rookie orientation.
As far as not returning your tools, you may be right, I don't remember that far back. But if you are implying I TOOK them as opposed to not walking a few yards over and handing each one to you then you are WRONG. I left Maxton with the same amount of tools I came with, basically some substandard and rudimentary wrenches and screwdrivers, maybe a ghetto batch of sockets.
Broke 1/2 your drills? Or drill BITS? I have never broken a single drill in my LIFE. I think my buddy and I broke 2 or more drill bits while safety wiring the front axel and pinch bolts. For that I apologize. PM me your email address with a dollar amount for your drill Bits and I'll send it over to you ASAP via paypal. If you like you can even calculate a fair amount of interest.
With all due respect I think you are a bit out of line here. I haven't seen you or heard from you since my 1st showing @ Maxton September 2005 and you try to rip into me on a public forum? I'm not hard to find, you could have PMed me on here or .org or the busa sites, psychobike, landracing, etc. That would have been the tactful and mature thing to do.
If you ever make it out to Maxton again (its been 14 months, not 2 years) you are more than welcome to borrow any sized socket, wrench, tape, zip tie, water, shade, gatorade, red bull, sprocket, a helping hand, even a nos refill if the rhythym of the weekend seems slow enough. Times have changed and a pick up truck, canopy, full socket set, and chair have replaced the geo metro, a flimsy basket of tools and jackstands for a bike stand.
Maybe you don't remember but after that botched run I got reamed by the heads of the ECTA and even my buddy punched me a couple times cuz he thought I was dead. Thats quite a bit of emotion going through one's mind and body during that time. I felt pretty guilty about that, I did what I thought was right by not returning up a "live" track (from the drag racing world). I've already explained it countless times to several people on several boards. Fortunately there was still Sunday and it was a clear day so it wasn't a total loss.
Again this is 14 months ago and only NOW are you saying something, and tactlessly might I add. I have made a gesture of good will HOWEVER if you're still bitter about it then there is nothing I can do about. Ball is in YOUR court, buddy.
A.
|
NOS1290
Expert Class
Posts: 103
|
posted November 18, 2006 03:31 AM
quote:
--------------------------------------------------------------------------------
What Cams are you running?
--------------------------------------------------------------------------------
Running a megacycle X1 (.405"/ 255 degrees) on intake. Running a X5 (.384" / 251) on the exhaust. Lost one lobe during break in that needed to be repaired, but otherwise its an almost streetable combination. I would recomend stainless valves if you are going through the head. Again, I melted the head off an exhaust valve TWO YEARS AGO.
Ship- Your right, you left my generator and tools scattered over the tarmac 14 months ago, but thats not the motor incident I was refering too on this post. As usual, you assume too much.
|
shiphteey
Needs a job
Posts: 2529
|
posted November 18, 2006 08:38 AM
Has the thought ever occured to you that maybe I didn't get to it as fast as you would like? Its pit, I was working on a bike, then I went to race it. Don't worry bro, based on your tone I'll ASSUME you are still bitter even though I've apologized. Can't change the past but if you still want to hold a grudge thats up to you. I'll stay outta your way, you can stay outta mine. Simple.
A.
|
|
|
HOME
NEW TOPIC