ESR PV broke....need pictures

[Burns310r]

Well i tore my top end off my ESR 330PV powered MX 250r last weekend due to a loss in a lot of compression.

When my old man that lives 45 minutes away took the PV out tonight to get the cylinder bored over and the PV came out in 2 pieces.


He told me that the shaft is all beat up on the end and isn't attached to the slide anymore. How is this possible? Does this mean that my PV wasn't sliding up out of the way?

What stopped it from dropping into the cylinder?

Can someone post some close up pictures of the PV slide so i can see how its attached? Im not able to make it to his shop for a few nights and im very curious on what the heck happened?

Im so fed up with this ESR cylinder. Was sticking pistons all last year. (Now ESR tells me to bore the piston to .004 clearance, hope that works). And now the slide is broken.

Thanks guys.

I wonder how much its going to cost me to get a ESR PV overnighted here so i have have it by friday.

[Burns310r]

Also,

What are the options for a better replacement. I do not want this to happen again.

Mine was threaded into the slide. Do they make a solid one that cannot come apart?

[latheboy]

Mine came unthreaded and ruined the threaded portion on the stem also. Esr replaced mine free of charge. The one they put in is a different design. There is a step in the pv port that keeps it from totally falling into the cyl.

[Burns310r]

Ya ESR charged me $50 for the slide, and 40 to overnight it. Have i ever mentiond how much i like them.....


I will be getting the updated slide though.


Now the question is how do i relieve the slide to fit the overbored cylinder?

Using it with the boring bar probably wont work will it? Just manually remove the material? How much clearance do i need.



I just cannot believe that ESR doesnt know how much material needs to be removed for each of there over bores? I mean seriously...

Anyways, im frusterated if you cant get that. Onward and upward. I will make this race this weekend with my new Laeger CR500 link setup.

[latheboy]

Right or wrong... When I overbored mine, I removed material from the PV slide with a sanding drum and a drill press. It wasnt hard to do. Last time I got the cylinder from ESR (they bored and replaced a PV) the PV slide was still touching the rings on the way by. I removed material until I had about .010 clearance. I just installed the PV, and held a scale across the exhaust port to see the clearance.

[Burns310r]

So when i resleeve this cylinder, i will have to buy a new power valve as well.

[latheboy]

For the powervalve to work its best...probably. Someone told me (cant remember if it was LED or ESR) that the powervalve should be as close to the piston as possible. I got the .010 figure from one of those guys.

[Derrick Adams]

We had problems with sticky pistons in our last motor too. Switched from Wossner to Wiseco pistons at .003 and no more issues.