Pro x vs Vertex Motorcycle Pistons?

[adnohguy]

In my experience, the Pro x is lighter than the Vertex, with or with out “rings, pin and clips”

Either way I would not either brand be installed that is more heavy than a stock OEM piston assembly.

[Rheemed]

2 minutes ago, adnohguy said:

In my experience, the Pro x is lighter than the Vertex, with or with out “rings, pin and clips”

Either way I would not either brand be installed that is more heavy than a stock OEM piston assembly.

Light or heavy. Unbalanced means more vibration. 

[Rob@ProX]

18 hours ago, seer said:

So...? What about mine? Box clearly states made in usa.

I dug a little deeper into this. There are a couple cases here and there where we don't have the demand on a specific part number to meet minimum order quantities in Japan, so those pistons end up getting manufactured in the US. Apologies for the confusion, I learned something too! 

[Motox367]

Japan doesn't wanna make stuff for ktm ?? makes sense to me 

[seer]

10 minutes ago, Motox367 said:

Japan doesn't wanna make stuff for ktm ?? makes sense to me 

Stock is japanese vertex. 

[Motox367]

9 minutes ago, seer said:

Stock is japanese vertex. 

Yep but not for long i bet

Edited December 12, 2018 by Motox367

[95jersey]

Decided on the Pro-x.  Bike has much better mid and top end with really good over rev.  The Pro-x piston was lighter than the Vertex and you can feel it is much snappier, almost 250 like. 

Very happy

[shrubitup]

32 minutes ago, 95jersey said:

Decided on the Pro-x.  Bike has much better mid and top end with really good over rev.  The Pro-x piston was lighter than the Vertex and you can feel it is much snappier, almost 250 like. 

Very happy

Was this on a 300 two stroke then?

[95jersey]

3 minutes ago, shrubitup said:

Was this on a 300 two stroke then?

yep

[adam728]

Decided on the Pro-x.  Bike has much better mid and top end with really good over rev.  The Pro-x piston was lighter than the Vertex and you can feel it is much snappier, almost 250 like. 
Very happy

I'm guessing fresh top end with more compression and less blow by has a lot more to do with what you are feeling than piston weight does.

[shrubitup]

30 minutes ago, adam728 said:

I'm guessing fresh top end with more compression and less blow by has a lot more to do with what you are feeling than piston weight does.

It's a thing. Going from cast OEM or Pro X to Wiseco "pro-lite" resulted in less piston weight and freer/faster revs in 250 MX bikes that I rode.

[Piney Woods]

The Pro lite single ring Wiseco in my CR250 definitely revs quicker than the dbl ring OEM. For woods use the OEM works better, smoother.

[Muffintop]

How much lighter are we talking here between a Pro X and Vertex? Somebody buy both for science!

[adam728]

Ok, I do understand piston weight makes a difference. And single ring definitely does due to friction. The point I intended to make was that it's very difficult to judge a performance improvement when things were due to be freshend up anyway. Sort of like replacing a half smashed and cracked stock pipe with something aftermarket, then claiming the difference was due to design and not condition. If things were past due then just re-ringing what was in there might have given the same performance increase.

[Piney Woods]

Agreed.

[95jersey]

 

1 hour ago, adam728 said:

Ok, I do understand piston weight makes a difference. And single ring definitely does due to friction. The point I intended to make was that it's very difficult to judge a performance improvement when things were due to be freshend up anyway. Sort of like replacing a half smashed and cracked stock pipe with something aftermarket, then claiming the difference was due to design and not condition. If things were past due then just re-ringing what was in there might have given the same performance increase.

I agree with your logic, but honestly, I feel an actual difference in power gain, compared to my previous refresh (at same hours).  The last refresh I did was with a Vertex piston, I didn't feel any noticeable change.  It was just business as usual.  With the Pro-x piston, the bike revs faster (250 like) and makes better mid and top power (and for once has some over rev), but I will say there is some definite loss of low end grunt (almost like removing flywheel weight).  It is a little softer on the very bottom, but then right at 1/4 throttle you get a nice kick in the pants all the way to the top.  The Pro-x piston definitely felt lighter in my hands, and you could visibly see less material on the piston compared to Vertex.  I should have weighted both.

Also to note, there was a small raised center section on the Pro-x dome vs the completely flat Vertex dome.  It was a very small raised circle about where the spark plug meets the piston.  I couldn't say how raised but you fingernail would easily catch it.

[turbo dan]

I think differences in piston weight are minute when you consider the mass of the crankshaft and flywheel.

Fresh rings helps, no doubt about it.

[95jersey]

10 hours ago, turbo dan said:

I think differences in piston weight are minute when you consider the mass of the crankshaft and flywheel.

Fresh rings helps, no doubt about it.

I am not talking 5hp, just the way the powerband feels.  It is different, more "revy" and free flowing.  Like I said, last refresh at same hours with Vertex resulted in business as usual.  

[turbo dan]

Sounds subjective.  Bike usually feels better after you work on it.

[Piney Woods]

Yep. Pistons/rings wear so little over a long period of time that we do not notice a power loss but it is still occurring. Stick in new(same) parts and the improvement is noticed. Kind of like gaining weight, happens so gradually and then one morning you're a slob!