Piston ?
- Thread starter Brian VT
- Start date
Trailrider
Member
GasGas piston
Just as an aside, I was told a few years ago ( I have a 2001 300) that the stock GasGas pistons are Wiseco made to their specifications. This may not be true anymore but either Jim Cook or Les told me this when I bought a new piston for my 300.
Trailrider
2001 XC300
1998 EC250 6 Days
Just as an aside, I was told a few years ago ( I have a 2001 300) that the stock GasGas pistons are Wiseco made to their specifications. This may not be true anymore but either Jim Cook or Les told me this when I bought a new piston for my 300.
Trailrider
2001 XC300
1998 EC250 6 Days
Skidad
New member
Well Vertex does make em for the bike. Someones gotta have one.
EC 300 300 2002-07 72,00 Replica
71,94 22981A
71,95 22981B
71,96 22981C
71,97 22981D
http://www.vertexpistons.com/Vertexlistino2008.pdf
Skidad
EC 300 300 2002-07 72,00 Replica
71,94 22981A
71,95 22981B
71,96 22981C
71,97 22981D
http://www.vertexpistons.com/Vertexlistino2008.pdf
Skidad
2 strokes 4 life
New member
I think it is true. When i was taking apart my 2002 GG EC250 it looks like the piston was machned from a forged block. But, they still dont make + size psitons.
Vertex lists 'em but I haven't found one to buy.
The new Vertex I got is 71.93, my bore is 72.02, the new ring's gap is .229
I guess the ideal piston would be a C (71.96). I'm not sure what the ring gap is supposed to be.
Should I run it or have the bore replated/sized ?
B.t.w., there was a Wiseco in there. There was some blow-by, but not bad for 3 seasons/3000 mi. on it. Ring gap was .381, Nikasil looks fine.
I probably should have left it until winter.
The new Vertex I got is 71.93, my bore is 72.02, the new ring's gap is .229
I guess the ideal piston would be a C (71.96). I'm not sure what the ring gap is supposed to be.
Should I run it or have the bore replated/sized ?
B.t.w., there was a Wiseco in there. There was some blow-by, but not bad for 3 seasons/3000 mi. on it. Ring gap was .381, Nikasil looks fine.
I probably should have left it until winter.
Last edited:
GMP
Active member
Brian,
If its a Vertex, in the box should be fitment table with the clearances. I think I have one at home, I'll look tonight. Also it might be found on the Vertex site, not sure, probably somewhere.
The thing you have to consider is that a Wiseco is forged and requires (was setup with) larger clearances. A cast Vertex runs tighter clearances. Thats why you go a size up easy. Don't sweat the ring gap.
How was the bore measured? If you don't use a proper 3 point bore mic the error will be greater than what you are trying to determine. You also need to measure it on several points to determine how far out of round it has worn, if any.
As far as OEM pistons, the original supplier was Wiseco up until '04 or '05, then Wossner, now Vertex. Did you call Town & Country, and Jack at RT&T?
If its a Vertex, in the box should be fitment table with the clearances. I think I have one at home, I'll look tonight. Also it might be found on the Vertex site, not sure, probably somewhere.
The thing you have to consider is that a Wiseco is forged and requires (was setup with) larger clearances. A cast Vertex runs tighter clearances. Thats why you go a size up easy. Don't sweat the ring gap.
How was the bore measured? If you don't use a proper 3 point bore mic the error will be greater than what you are trying to determine. You also need to measure it on several points to determine how far out of round it has worn, if any.
As far as OEM pistons, the original supplier was Wiseco up until '04 or '05, then Wossner, now Vertex. Did you call Town & Country, and Jack at RT&T?
eff
Silver Level Site Supporter
Road, Track & Trail Jack Bondus 763-427-2184
fax 763-427-0981 633 E. Main St.
Anoka, MN 55303 rttgasgas@hotmail.com
fax 763-427-0981 633 E. Main St.
Anoka, MN 55303 rttgasgas@hotmail.com
skid jackson
New member
because I could not get rings that worked in my stock piston I ended up with a piston and rings in a box marked for an 04 300. No mfg name on it, had some kind of black teflon looking stuff on the sides. I wonder if my 06 had a wossner in it and that is why the wiseco rings did not work?? Pain in the arse it was.
skid jackson
New member
go right to the source
http://www.woessner-kolben.de/english/indexenglish.html
looking at the chart for the 300 it gives 3 sizes ..
find out who the distributer is for out area call the distributer.
here you go usa distributor
http://www.woessner-usa.com/
notice the contact name for sales and technical assistance ....
tobias wossner ..... hmm same name as the companny ....
bet that dude will have a piston that works in your bike at your doorstep in days!!! I'd be on the phone to Cali moday morning!!!
http://www.woessner-kolben.de/english/indexenglish.html
looking at the chart for the 300 it gives 3 sizes ..
find out who the distributer is for out area call the distributer.
here you go usa distributor
http://www.woessner-usa.com/
notice the contact name for sales and technical assistance ....
tobias wossner ..... hmm same name as the companny ....
bet that dude will have a piston that works in your bike at your doorstep in days!!! I'd be on the phone to Cali moday morning!!!
eff
Silver Level Site Supporter
These Co. were listed on the site.
Distributors:
L.A.Sleeve
Niks Distributing http://www.niksindustries.com/pages/wossner.php
Racer's Edge
Johnston Research & Performance
Distributors:
L.A.Sleeve
Niks Distributing http://www.niksindustries.com/pages/wossner.php
Racer's Edge
Johnston Research & Performance
Ok. I appreciate the links. I sent an email off to Wossner and Niks.
I hope something comes of it tomorrow but I hold out little hope.
I've already lost a week making calls trying to find an appropriate piston.
So....assuming those are also dead ends...
Do I run the -.09 or have my bore replated to -.06 ??????
I hope something comes of it tomorrow but I hold out little hope.
I've already lost a week making calls trying to find an appropriate piston.
So....assuming those are also dead ends...
Do I run the -.09 or have my bore replated to -.06 ??????
skid jackson
New member
email????
email is too easy to ignore
Dude if you want any kind of response you gotta call them on the phone. a human voice is a little tougher to ignore. ask for technical assistance or customer service. technical assistance is best as it will usually get you someone who knows what they are doing. Customer service could be the secretary. I'd get on the phone to this wossner guy first!
email is too easy to ignore
Dude if you want any kind of response you gotta call them on the phone. a human voice is a little tougher to ignore. ask for technical assistance or customer service. technical assistance is best as it will usually get you someone who knows what they are doing. Customer service could be the secretary. I'd get on the phone to this wossner guy first!
WoodsRider
New member
When I rebuilt the top-end on my '03 EC300 last year I measured the cylinder first. It was stamped "A", but was worn to the point it needed a "B" piston. Luckily my local dealer, Marshall's, had a "B" Wiseco in stock. On all three of my Gassers, '98 EC250, '01 XC300 and '03 EC300, Wiseco was the stock piston. In fact the 250 used the same piston as the '86 to '96 Honda CR250.
Forged piston have a different grain flow than cast pistons, so you need to follow the initial heat-cool cycles when first starting the engine. The only other issues people seem to have with Wiseco piston is getting the wrist pin retaining clips properly installed. More than a few cylinders have been destroyed when a clip that wasn't properly installed and popped out.
Forged piston have a different grain flow than cast pistons, so you need to follow the initial heat-cool cycles when first starting the engine. The only other issues people seem to have with Wiseco piston is getting the wrist pin retaining clips properly installed. More than a few cylinders have been destroyed when a clip that wasn't properly installed and popped out.
