I have not heard of any DS builders that will test out your motor before they ship it to you. Im sure they would do it if you were willing to pay, but that would be alot of time. If you ship your whole quad then thats another story.

This particular issue with TVI and Bigboo, even if TVI tested the motor and it ran fine, Bigboo would of still ruined the motor by running the wrong fuel.

 

Absolutely correct.....

 

I agree.........but with running the motor(for even a small amount of time.....like similar to a engine dyno)........you(the builder) would have known nothing is wrong with the engine, and that it was tuned correctly, and ran good. The particulars(fuel, cdi).....could be covered in a piece of paper handed to the customer.....leaving the rest in their hands.....

 

Utopia.......

 

I have seen this happen a few times also.

He is lucky the gasket is what went and not the piston or as stated above a rod bearing. 9 times out of 10 the head gasket will be the first to go, unless the cylinder and head have been set up. Ie grooved head etc. Detonation is a very nasty thing.

 

When building a race motor it is best to know what you are getting into. I think most of us learned via the school of hard knocks when it comes to detonation. There are lots of resources that can help you. Racers and motor builders are usually the best source of information. Here are some facts about detonation:

Detonation/ Pre ignition is a saw tooth waveform that forms in front of the ignition front. The pressure spike caused by the saw tooth waveform(detonation) is thousands of times greater than that of normal compression in a motor.

The head gasket is usually the weak link and the detonation will blow the head gasket. A copper head gasket is stronger and just changes what is the weakest link. Detonation will now burn a hole in the piston top or wreak havoc on the bottom end bearings. You need to treat the problem not the symptoms. There are many, many variables that contribute to detonation. Octane being the one that is easiest to change. When you increase the octane you can eliminate detonation.

Here are a few of the things that affect detonation. Ignition timing, Octane, Intake air temperature, a/f ratio, altitude, compression ratio to a lesser degree, Dynamic compression to a greater degree, cam (yes this will affect dynamic compression), load on the motor, rpm, squish area. This is all I can think of off the top of my head but I'm sure there are more.

Bottom line - detonation is a very bad thing. If you want to make sure your motor lives you need to be proactive and prevent it from forming. OCtane and timing are usually the easiest things to change. There are a few good resources on the net to look into. One that I remember using was gasfaqs.com orsomething close to that. Google it. Good luck!

 

Ok......guys.......I was just wondering.....as being a novice on engines I guess.......how do you spot predetonation? I understand what it is, and what it is caused by(from many posts, and from the above)..........so how would I know if I had it???? I assume by listening to it knock(that is my guess)........

 

Just to calrify. I'm not saying setonation definitely was or wasn't the culprit here. I just wanted to clear up some facts aout detonation/preignition.

I thought of two other factors that contribute to detonation: Contour of the combustion chamber(sharp edges seem to produce detonation), and throttle position(everyone has heard pinging in the motor and let off the throttle a bit to make it go away).

 

Thats it im sueing bombardier they never told me if i run propoxide @40% that it might blow my motor[img]i/expressions/face-icon-small-happy.gif[/img] causing various parts to fly threw peoples windshields[img]i/expressions/face-icon-small-shocked.gif[/img]


But seriously guy do your home work next time !!!!!!
And guy's even my pami leaked out the head gasket after a few thousand pass's And for the record i have dealt with many builders and suppliers on this forum and tvi whommps in customer service.And no one and i mean NO ONE HAS DONE A BETTER JOB OF SUPPLING ME WITH PARTS THAN TVI

And for the record a ron woods cdi +13-1 comp+pump gas by by motor!!!!!!!!!!!!!!![img]i/expressions/face-icon-small-tongue.gif[/img]

 

" Gary Tiffany was very unreasonable when trying to work this problem out."

Sounds like great customer support to me.

Bigboo give HPR a call.... I can guarantee you you will get a totally different attitude with Randall, then post your report. Not sure if they would help fix your problem but they offered to help me in the past with my kit.