Something happened while on the Dyno.. anyone able to help

Skywalker86

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While the Busa was on the dyno for its first run in 3rd gear the bike shut off after it came to idle and when the dyno guy put the bike back on to do a run in 4th, when he started it there was a loud snap and the bike ran real bad like it may be only running on 3 cylinders. if anyone can watch the video and maybe have an idea what may have happened, incase its not a serious as we think and dont pull the motor down if not necessary... thanks in advance..

https://vimeo.com/user94747627/review/321937175/72b970c3e3
 
You will want to test your link in a browser that is not logged into vimeo. I am getting "sorry we could not find that page" message when I click on your url.

Some history of the engine may be helpful. Was maintenance performed according to the schedule? Was any maintenance performed in preparation for the dyno?
 
i will try and upload via youtube but when i get hm to my computer..
the bike hadnt been ridden for about 4 months. the motor has done 90000km but was supposedly rebuilt with forged internals 10000km previous to me purchasing it..
pc111
upgraded inj
yoshi single exhaust
aftermarket cams + adj cam gears(i cannot confirm this though workshops have told me it must do due to the sound of it)
I sent it into my friends performance shop to get running as the fuel relay was gone and throwing f1 code so while it was there i said chuck it on the dyno and see what power its running as previously in a different shop it made 186hp so i was curious what itd make on a different dyno
 
Ok so this is the new upload of the video any advice or thoughts will be appreciated, maybe someone will be familiar to what happened..

 
Really hard to tell from the video...I watched it 3 times and couldn't pin-point the noise. I think pulling the plugs and checking compression will be the best bet to start or at leat checking the plugs, seems one cylinder went dead in a hurry.
 
Really hard to tell from the video...I watched it 3 times and couldn't pin-point the noise. I think pulling the plugs and checking compression will be the best bet to start or at leat checking the plugs, seems one cylinder went dead in a hurry.

Its at exactly 1.34 into it.. yeah we will be doing the compression test next couple days.
 
Its at exactly 1.34 into it.. yeah we will be doing the compression test next couple days.
I heard it that time, sounded like a "tink." I hate to speculate what that was, hopefully it wasn't expensive. I think a compression test is the best thing...that was definitely metallic.
 
I heard it that time, sounded like a "tink." I hate to speculate what that was, hopefully it wasn't expensive. I think a compression test is the best thing...that was definitely metallic.

Yeah thats what im thinking it definately isnt a good sound.. i think he really over revved it to 11000rpm or close to it because the shift light is set to 9k and he was on the throttle for quite a while after it came on..
 
I have heard a busa throw a rod and it didn't sound like that to my ears. The time I watched it happen it was a muffled boom and then a lot of clanking. Maybe something in the top end. Not to lay blame but the position of the fan was not blowing air into the radiator. This is a no no, probably not the source of the problem but you would have had overheating problems eventually running the dyno runs like that. The over-rev is a potential issue though.

This is also a car dyno, which is not as good or accurate for a bike, but people use them all the time for this sort of dyno run. Well dyno runs are brutal to a bike and you should generally only do them when you have to. There is a lesson here (BTW: not saying that this was just a "ego run").

Anyway hope it's something relatively simple. Thanks for posting this, its a great reminder that dyno runs are brutal to a bike and make sure you have a guy that knows what they are doing (not that your guy doesn't, stuff happens it's possible whatever let go was going to do it on your next ride).
 
I have heard a busa throw a rod and it didn't sound like that to my ears. The time I watched it happen it was a muffled boom and then a lot of clanking. Maybe something in the top end. Not to lay blame but the position of the fan was not blowing air into the radiator. This is a no no, probably not the source of the problem but you would have had overheating problems eventually running the dyno runs like that. The over-rev is a potential issue though.

This is also a car dyno, which is not as good or accurate for a bike, but people use them all the time for this sort of dyno run. Well dyno runs are brutal to a bike and you should generally only do them when you have to. There is a lesson here (BTW: not saying that this was just a "ego run").

Anyway hope it's something relatively simple. Thanks for posting this, its a great reminder that dyno runs are brutal to a bike and make sure you have a guy that knows what they are doing (not that your guy doesn't, stuff happens it's possible whatever let go was going to do it on your next ride).
Totally agree man i wasn't thinking it was gonna be tough on the bike and only wanted to see how the bike was still doing as its been 6or7 years since it was on the dyno last
 
Propagating the falsehood that dyno runs are brutal to a bike is just wrong, and a disservice to dyno technicians everywhere ! Why don't we just wait and see what they find? Whatever this bike did most
likely would have happened just riding down the street. I have very close to 20 years of dyno tuning
bikes of all kinds, from Groms to big horsepower builds, both normally aspirated and blown.
This is not to say that I agree with the bike being on a car dyno, or making pulls in third or fourth . . . do NOT blame the dyno . . . or the dyno operator, yet. NOT fair and WRONG !
 
Propagating the falsehood that dyno runs are brutal to a bike is just wrong, and a disservice to dyno technicians everywhere ! Why don't we just wait and see what they find? Whatever this bike did most
likely would have happened just riding down the street. I have very close to 20 years of dyno tuning
bikes of all kinds, from Groms to big horsepower builds, both normally aspirated and blown.
This is not to say that I agree with the bike being on a car dyno, or making pulls in third or fourth . . . do NOT blame the dyno . . . or the dyno operator, yet. NOT fair and WRONG !

Yeah i agree i wasnt putting any blame on the shop at all just wanted to see if anyone has any advice thats familiar with the hayabusa before we tear it down incase its a simple fix..
 
Agreed with Frank. My personal Busa has 200 to 250 dyno runs on it. Still cranking out great power. It was always the test mule for dyno software and hardware upgrades. It has also spent a long time doing steady state operation that didn't result in a dyno chart being produced because we were collecting live data or tweaking other parms.

But, she's well taken care of.

Byron Hines once said a single drag strip pass puts about the same wear and tear on a motor as he has seen after about 100 dyno pulls. I don't now how accurate that is, but I like to believe it. I often tell people, "Can I put a fat guy on your bike and send him up a hill? If I can't, then you don't want to put it on the dyno. (AND I don't want to ride it.) If you can do the fat guy test, the bike will be fine."
 
Honestly, the sound i heard was almost like engaging a starter when its running already. That would not explain the shty running though i dont think.
 
I have to agree with Frank, i had a friend decide to put a cheap manual chain tensioner in his 98 srad and while being stupid in a parking lot revving the hell out of it we all heard it let go. Can't say it sounded exactly like that because of it being video but was similar sounding
 
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