Engine Problems

[nwi45]

I was riding at an open ride, comin out of a corner, and my bike died. Wouldnt start, had really low compression. When I got back to the pits, I was gonna check my plug. When I went to check it, I noticed that the skinny nut on the top of my PSI Dial-A-Dome head was compleltly unscrewed. I'm hoping this is what cause the low compression. How do I go about fixing this? I can't get in touch with PSI ever about anything...

[nwi45]

Nobody?

[wilkin250r]

First off, you're asking about a particular engine kit that very few of us have any experience with. I don't know anything about the dial-a-dome head.

Second, you're question is really vague. Your bike died, and had really low compression, and you noticed a nut on the top of the head was loose. How in the world are we supposed to be able to diagnose your problem from that information?

You want advice? It's very simple, and very generic. You need to tear apart your top end and figure out what the problem is. Once you figure out the problem, you need to fix it, and then put your engine back together.

It's foolproof advice, works every time you have a top-end problem.

[nwi45]

Sorry mann, I was just using the "Nobody" as a bump.

I tore apart the top end when I got home. The piston is no good but the cylinder doesnt seem bad. My main concern is what cause it...Would it be a good idea to ditch this dome and buy a new one? PSI has horrible customer service, so I can't call them to get any tips or advice.

[wilkin250r]

I've heard that PSI has terrible customer service.

I don't know enough about the engine kits to give you advice. Why do you think you need to replace the dome, is it cracked, burnt, melted, or some other problems?

How is the piston shot, but the bore is good? Aside from normal wear, I can't see the piston going bad without taking the bore with it.

I can't really give you advice without being there in person, you might try to find a local shop. Anybody that has experience with 2-strokes, even if they don't have any experience with PSI, they know what to look for in general, and can inspect your engine and tell you which direction to go.

[250-R-250]

What signs does the piston have? I know that several different things can go wrong that can cause a piston to be trashed as well as the bore. Maybe you could post some pics of the piston and cylinder walls.

[nwi45]

Thanks for the advice guys..I'll post pics tomorrow to see if it helps anybody out.

[machwon]

Sounds like the possibility of some detonation problems, pictures could help decide. What type of fuel are you using?

[nwi45]

VP..can't think of the exact name off the top of my head.

[nwi45]

wilkin250r, I want to replace the dome with something I understand and know how to work. I am most likely going to replace it with a stocker, or a non-adjustable aftermarket. I don't want something that I don't even know how to set up, because when I get my engine back together I will most likely run into the same problem.

The piston is just a little melted in the front, still all in tact.

I took some pics of the piston, couldn't get any good ones of the cylinder walls. What are the rules for play on the rod?

[nwi45]

Here's another...

[nwi45]

I dont know what happened to the first one..haha