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pro-rider46
12-17-2008, 09:27 PM
will my +1mm exhaust vavles clear my stock piston?

d3ktrix
12-17-2008, 09:47 PM
+1 valves have a larger diameter, they are not actually longer.
They shouldn't be any closer to the piston then stock valves.

pro-rider46
12-17-2008, 09:50 PM
i know it is diameter. but i didnt want the the bigger valve to not fit into the small valve pocket

d3ktrix
12-17-2008, 10:18 PM
Who ever ported your head would of cut the seat larger to take the larger valve.

pro-rider46
12-18-2008, 01:37 PM
the head is cut for +1mm valves. but im talking about the valve pocket on the piston, sorry i didnt clarify.

rt20ps
12-18-2008, 01:57 PM
No problem with a stock piston. When you get up in the really high compression ratios the piston pockets can be cut.

pro-rider46
12-18-2008, 02:28 PM
ok, im going put it on and slowly turn the motor over to see if everything clears, thenks guys

d3ktrix
12-18-2008, 02:40 PM
Originally posted by pro-rider46
the head is cut for +1mm valves. but im talking about the valve pocket on the piston, sorry i didnt clarify.

Ah my bad.
I didn't think you would ask something like that :P

But yeah, can't really say I've ever herd of anyone using +1 valves with a stock piston.
Though the 05 stocker doesn't have much for valve reliefs, its pretty flat being such low comp.

Let us know how it goes when you stick it together.

pro-rider46
12-18-2008, 04:33 PM
yeah the reliefs are small being low comp like you said. i will keep you guys updated.

Im thinking about splitting the gasket to only being a two piece to raise comp. what do you guys think

i have a 12.5:1 piston that i can probably run, but i dont want to chance anything, and i dont feel like putting a piston in just yet.

400exrider707
12-18-2008, 08:45 PM
Instead of pulling a gasket apart, get a custom cometic gasket, they'll make pretty much any thickness, and why bother with +1 valves on a stock piston? I guess if you just happen to have it or something it should work, definitely turn it over by hand first though.

pro-rider46
12-18-2008, 09:41 PM
oh thanks never thought of cometic

and i got a head ported by DRG with oversized ex. valves, kibblewhite spring kit, ferrea intakes, and only has about 5 hours on it. so i thought i would throw it on

GOTFEAR
12-19-2008, 09:49 PM
all after market pistons should accommodate a 1mm oversize valve but not 2mm

pro-rider46
12-19-2008, 10:34 PM
Originally posted by GOTFEAR
all after market pistons should accommodate a 1mm oversize valve but not 2mm

what about stock?

d3ktrix
12-19-2008, 10:41 PM
Why not just stick the 12.5:1 in there? Or are you saving it for another bike?

Feels like your wasting the potential of that nice port job using that stock boat anchor lol.

pro-rider46
12-24-2008, 10:04 AM
Originally posted by d3ktrix
Why not just stick the 12.5:1 in there? Or are you saving it for another bike?

Feels like your wasting the potential of that nice port job using that stock boat anchor lol.

well it has a few scrapes on it, and i wanna have Chad check it out for me to double check that its alright, otherwise i would already have it in their lol.

pro-rider46
12-29-2008, 09:53 AM
well i put the head on last night, and slowly cranked the motor over by hand and closely listened, and all is smooth the no funky noises, and she started right up this morning without any issues. and she runs like a champ to. next on my list is a new piston and FCR

400exrider707
12-29-2008, 10:12 AM
What did you end up using for a gasket? I tried the pulling the gasket apart trick before on my 400ex and it never worked right, it always leaked. I even added more torque to the head bolts and it still leaked. I put the cometic thin on the 400 and it sealed right up and never leaked again.

pro-rider46
12-29-2008, 09:45 PM
just got a stock one from the dealer, but the next time i pull it apart i will put a cometic thin one in there.