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Piston Alternatives for EG295 top ends?

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Are there any other known applications or sources for a piston compatible with the Eric Gorr 295?

I'm aware that the replacement piston kits can be purchased through EG, but I'm looking for a different source.

My preference is the Wiseco brand, however I'm not opposed to other brands as options.

Thanks!

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If the top of the cylinder is decked and you are running a head gasket odds are you have a Wiseco. Wossner also has a piston that will work. They are basically a generic 72mm piston that will fit a number of 300's.

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1 hour ago, 218 said:

If the top of the cylinder is decked and you are running a head gasket odds are you have a Wiseco. Wossner also has a piston that will work. They are basically a generic 72mm piston that will fit a number of 300's.

Yes, I believe he takes about 3mm to 4mm off the top of the casting and runs the MLS type gasket, so the pin to crown height is lower than a stock 250cc piston.

The pistons he delivers with the top end kit are Wiseco with a custom part number.   I have a feeling they are a generic 300cc (72mm) piston, but don't know the base application to order them from a different vendor.  

I thought about checking into the KTM 300 pistons, but are the ring-locating pins in the same position?   Crown height?   Skirt length?
 

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You can double check with Wiseco but I'm pretty sure he's just using a 878M07200 based piston, which is commonly used in many big bore applications.

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49 minutes ago, 218 said:

You can double check with Wiseco but I'm pretty sure he's just using a 878M07200 based piston, which is commonly used in many big bore applications.

That number looks right.   I've searched for it on the retail parts websites, nothing comes up, but I see about a million of them for sale on e-bay.
Now if I can find a source for the 72mm MLS gasket I'll be set.

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Look here

Cometic C3592 gasket kit should be what you need.

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6 hours ago, 218 said:

Look here

Cometic C3592 gasket kit should be what you need. 

Thanks, but that looks like a four stroke gasket kit.

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Don't let the picture fool you. That's the correct part number for the two stroke kit. Run the part number on google if you don't trust me. There are others on ebay with the correct picture.

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This is right from the Cometic catalog:

YZ250 02-16 72mm C3592 72mm Bore Kits $49.40

72mm Bore H0873SP2020S Cylinder Head Gasket $49.40

w/Head Gasket B0372032AFM Base Gasket $7.44 5CU-11351-00

PV082018AFM Right Side Power Valve Gasket $7.44 5CU-11993-00

PV083018AFM Front Power Valve Gasket $7.44 5CU-11354-00

R016B Power Valve Governor O-ring $0.74 93210-15639-00

R54X3V Exhaust Gasket 2-Req. $3.57 93210-53638-00

IR114018AFM Intake Gasket $3.80 5NX-13622-00

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18 hours ago, cwtoyota said:

Now if I can find a source for the 72mm MLS gasket I'll be set.

In case it helps ... I don't remove the head to swap a YZ250 or 295 piston. I've bought about seven 72mm pistons but only bought a couple of the steel 72mm gaskets for times I wanted head mods.   But I have the 2004 steel frame.  Maybe the alum frame has less clearance. If yours is tight to remove then maybe you can grind down the cylinder studs to be 2 or 3mm shorter. I did that and it makes the job easier.   You can use a single layer steel head gasket too if you want to tighten the squish and/or raise the comp. They seal fine, but I do use a thin layer of copper coat spray on both sides.

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5 hours ago, numroe said:

In case it helps ... I don't remove the head to swap a YZ250 or 295 piston. I've bought about seven 72mm pistons but only bought a couple of the steel 72mm gaskets for times I wanted head mods.   But I have the 2004 steel frame.  Maybe the alum frame has less clearance. If yours is tight to remove then maybe you can grind down the cylinder studs to be 2 or 3mm shorter. I did that and it makes the job easier.   You can use a single layer steel head gasket too if you want to tighten the squish and/or raise the comp. They seal fine, but I do use a thin layer of copper coat spray on both sides.

Thanks, there is enough room in both frames to do a top end without pulling the head, I do it that way too.

I am thinking about running my big bore cylinder for the summer in vet class and I'd like to get some spare parts.
All my spares are 250cc since the 295 has been sitting on the shelf for about five years.

 

Hey 218, don't take it personally, I appreciate your help and part numbers. 
I clicked on that e-bay link and saw photos of a four stroke gasket set.  Looks like they just used a stock photo rather than the one for each specific make/model.

 

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