6.5 flat top piston with Milled head too Much??

125ccCrazy

125ccCrazy

Well-Known Member
#1
#1
I have a 6.5 that I am going to build, I dropped the head off to get milled .065... My questions are, Will a flat top piston with the head milled be too much compression?? next question: which engine has teh flat top piston stock?? gxv160 mower engine or the gx160 horiz shaft eng??

I'll be getting a billet rod and either a billet flywheel or a gxv160 alum flywheel, most likely the billet.... I am also looking at a 265 lift cam... I'll probably be running a vm22 or 24mm mikuni, not sure on the carb yet, I have to get more info on that part, which one will work best?..
 
Strigoi

Strigoi

#2
#2
i was told that it would be ok on a 5.5. i plan on running a flat top and millilng the head 0.10.

you'll probably need to run 110 octane or higher at that point. that stuff is $12 a gallon around here.
 
125ccCrazy

125ccCrazy

Well-Known Member
#3
#3
Strigoi said:
i was told that it would be ok on a 5.5. i plan on running a flat top and millilng the head 0.10.

you'll probably need to run 110 octane or higher at that point. that stuff is $12 a gallon around here.
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yeah definately race gas (Cam2), it's about $5.50 to $6 a gal here.. We run that in our other bikes..

I just don't want to get it all together and not be able to pull it over..
 
125ccCrazy

125ccCrazy

Well-Known Member
#5
#5
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Strigoi

Strigoi

#6
#6
those are different. my buddy has installed them here at work. they go into the spark plug hole from what he said. there's a chance they may be aftermarket. i don't feel like looking right now or bugging him about it.
 
125ccCrazy

125ccCrazy

Well-Known Member
#7
#7
Strigoi said:
those are different. my buddy has installed them here at work. they go into the spark plug hole from what he said. there's a chance they may be aftermarket. i don't feel like looking right now or bugging him about it.
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there are some others but from what I read they fit in the second plug hole for dual plug heads?? I dunno.. all the ones I have found look pretty much the same and require a second hole..
 
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Strigoi

Strigoi

#8
#8
125ccCrazy said:
there are some others but from what I read they fit in the second plug hole for dual plug heads?? I dunno.. all the ones I have found look pretty much the same and require a second hole..
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i don't know. he said it would work on my motor and we should try one once i get the compression bumped up.
 
Stang

Stang

Member
#10
#10
Need more information.
What motor: GX200 or GX160?
What cc head to begin with: 14cc(Early GX160), 18cc(Late GX160), or 22cc(GX200)?
What head gasket: .010 (GX200 Gasket) or .045 (GX160 Gasket)?

Assuming this is a 6.5 clone, with a 22cc head and GX200 gasket, your looking at around 11.4:1 CR which is fairly mild still for one of these. Many people go up to 14.1:1 or so with a decked block and 14cc head.

Most GX200 cams already have a compression release, you think you need another?
 
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125ccCrazy

125ccCrazy

Well-Known Member
#11
#11
Stang said:
Need more information.
What motor: GX200 or GX160?
What cc head to begin with: 14cc(Early GX160), 18cc(Late GX160), or 22cc(GX200)?
What head gasket: .010 (GX200 Gasket) or .045 (GX160 Gasket)?

Assuming this is a 6.5 clone, with a 22cc head and GX200 gasket, your looking at around 11.4:1 CR which is fairly mild still for one of these. Many people go up to 14.1:1 or so with a decked block and 14cc head.

Most GX200 cams already have a compression release, you think you need another?
Click to expand...
gx200 head (clone)
.010 head gasket
flat top piston

I don't want the compression so high I have to use an elect starter every time I want to start it, I was figuring 12:1 max on compression..

I thought about the stock compress release, should I keep that or go with a release valve??
 
pro69nova

pro69nova

New Member
#14
#14
125ccCrazy said:
gx200 head (clone)
.010 head gasket
flat top piston

I don't want the compression so high I have to use an elect starter every time I want to start it, I was figuring 12:1 max on compression..

I thought about the stock compress release, should I keep that or go with a release valve??
Click to expand...

stock compresion reslease works fine, i have motors onver 12 to 1 and you can still pull start it........
 
TT

TT

#15
#15
Stang hit the nail on the head. I sent my head out not knowing it was 22cc. It's coming back as is and I am getting a different head done for more compression.

14cc 18cc OK
22 cc no go $12.00 waste of shipping to save $50.00... lol


TT

OUT!

Good luck!

reogjrejgerjgrejgorijgoirjgoirjgjreoijrjrwreio 12.5 to 1 minimum.....:doah:
 
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