Yt60 exhaust port doesnt fully open bdc

Hey I'm doing a yt60 project and my piston does not clear by 1mm or so and I was wondering if any adverse affects could happen because of that. I plan to raise the jug and deck the top buttttt I was wondering if this was okay in the meantime

Re: Yt60 exhaust port doesnt fully open bdc

Isaiah Rolon /

Dis be the picture

Screenshot_20210128-213222_One UI Home.jpg

Re: Yt60 exhaust port doesnt fully open bdc

you're fine, i ran mine like that for a while, just won't get the super top end if ya raised the deck on it

Re: Yt60 exhaust port doesnt fully open bdc

Isaiah Rolon /

I figured if I raised the cylinder I would get more power with the third transfer opening more and the exhuast fully opening. I would remove material from top of the cylinder to get around .8 squish (edited)

Re: Yt60 exhaust port doesnt fully open bdc

Probably Fred /

Base space the cylinder because you don’t want the piston’s bottom side or a ring in the exhaust port, because it could get hotter then the rest of the piston (It’s already hotter than the top intake side to begin with) and or ring and you could snag a ring or score the cylinder

Re: Yt60 exhaust port doesnt fully open bdc

Get a 1mm sheet of aluminum and make a space. Maybe .8 so you can use a gasket on both sides. I got a roll from homedopt for like $5. You can get it on Amazon but it will cost more. Hi were it is worth it because It will change a lot. Treats might even have spacers now. Can’t remember. Edit (just checked they have hobbit ones you maybe can make work. eBay might have ones. I think the call it a speed plate.) Like Ken said it is not good to let the top ring sit in the exhaust port at BDC. I have done this on a Yamaha before and it still ran good without decking the cylinder. Sure it will lower compression, but it will run way better than it would with the piston in the exhaust port. (edited)

Re: Yt60 exhaust port doesnt fully open bdc

Jack Rutherford /

Re: Yt60 exhaust port doesnt fully open bdc

I think you better measure to make sure it's only a single mm .

Looks closer to 3 or 4 mm .

Re: Yt60 exhaust port doesnt fully open bdc

Isaiah Rolon /

Can't be any more than 2mm. I've have 1mm karropak sheets to compare it to. Not gonna lie I have stacked karropak gaskets in the past to get proper squish but I do have a sheet of copper at my disposal.

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