I was riding yesteday and my quad just died out... it felt like someone was pulling it back or something... so i started it up and went about 5 yrds. and it did the same thing so on the way back it kept doing and doing it and finally it made some horrible noise and just died and wouldn't start so later on when i picked up we got it back and it did start but its stil doing the same thing... I was thinking it wad my valves but my friends dad it sounded like it was the piston slapping against something. Does anyone know what this might be and how much it will cost to fix. I just got a brand new top end not even a month ago and I would hate to have to bring it to the shop.

Do you have a air compressor and know how to put crank in top dead center.

Mine did the same thing this weekend....I think that I lost a ring.

Pre-detonation?

What kind of fuel are you running?

Check your plugs? What do they look like?

Why did you do top end work on your quad? Did you put in a high compression piston?

Will the problem only present itself after being warmed up?

What kind of riding were you doing when the problem presented itself? A hard pull up a hill?

Majorecho had a pre-detonation issue and may be able to help you with what it sounded like so you can compare to see if it is the same issue.

Did your shop do your top end work? Why not take it to them if it was less than a month ago.

have you checked your cam chain tension? the tensioners do go bad.

I am running 93 octane.... I was doing trail riding when I first heard the chattering and when it first shut down I was going over whoops. The put new gasgets and a piston kit in oem piston. It did present itself about 10-20 minutes of riding. It was already warmed up. I was riding earlier but my radiator hose went so I came home and put a new one on and refilled my coolant and 10-20 after that the quad just shut down.



-No I havn't checked my cam chain tension.

When your rad hose came off the first time, did the red light ever come on? Are you sure the red light works? Does the red light come on when you turn the key on and go out when the motor starts? If the top end was cooked. You may have the beginings of a seize.

You have more than likely have done one of two things. 1. Your cam chain tesioner collapsed, which in any case doesn't make sense why you couldn't rev it up abouve 2500 RPM. You would still be able to run it above 2500 rpm's no problem.
2. You have maytagged your Rod bearing at the crankshaft or the piston pin. Drain your oil and check for Brass debris. This is what happened to Mario's bike this weekend.

Is there any compression?
why did you have to replace your top end?
Who did the work?
did they use factory parts?
did you break it in before hammering on it?
How long did it run without coolant? .....sorry, just thaught it looked like fun...I'll stop now

But really does it have any compression?....dammit..there I go again[img]i/expressions/face-icon-small-confused.gif[/img]

I'm sure the motor overheated after it lost coolant and was still running. You are looking at another engine rebuild. Drain the oil and look for metal in the oil.