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cylinder specs

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There is no THINKING LIKE in torque specs. Not to mention, you don't go right to max torque on your cylinders, it's a two stage torque process. First stage is 15 ft. lbs, second and final is 30 ft. lbs all in a criss-cross pattern for each cylinder WITH the exhaust manifold bolted up to align the cylinders. There is no half ass-ery in engine building if you want your stuff to hold together. I take building an engine very seriously, everything has to be 110%, every hole has to be tapped clean to obtain proper torque, no old chit in the threads. You just can't skip a step. Sorry to be harsh but I have to be truthful here.

You're right on that. I actually do all the things you say, and have the manual open during every build. Forgot the two stage torque sequence tho. My bad. Don't forget to grease the shanks and apply the loctite ;)
 
so i have 2.0 mm squish . and a 6 hole gasket. do i NEED to replace with a 4 0r 5 gasket or can i leave it without issue.
 
specs are 1.2mm-1.6mm (.047in-.063in)
3 hole base is .3mm
4 hole is .4mm
5 hole is .5mm
6 hole is .6mm
 
The range for your squish is 1.2mm-1.6mm at 2mm your squish is to big. Are you measuring directly over the wrist pins?

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Lets talk straight decimal from here on out. Your current squish is 0.078". You're 0.015" out of MAX spec (0.063").


3 hole gasket is 0.011"
4 hole gasket is 0.015"
5 hole gasket is 0.019"
6 hole gasket is 0.023"


You would need to run a 3 hole gasket to be just over the high end at 0.065"ish

See, isn't it just easier to use the decimals?

As 1of500 said are you measuring over the wristpin? What I like to do is rotate the crank to come up to TDC, the rotate CCW a 1/4 turn. Bend the solder in an arc and insert it into the spark plug hole and make sure it contacts the cylinder wall. Then SLOWLY rotate the crank back the CW until I just touch the solder, then CCW a hair and then a quick bump back CW past TDC.
 
Gentlemen . i understand and know the limits and am obviously out of range, But do I NEED to drop down, i understand there may be a drop in performance but i can live with that if its not going to harm the motor or prematurely shorten the life etc. Ive read its ok to be over the limit some but not too short. Too small squish risk detonation, too large performance . Yes measured over wrist pin and both sides and to the edge of cylinder , proper torque values adhered to.etc.
 
Well, I thought i was pretty clear that you needed a 3 hole.

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i know you probably think im being thick headed but , yes you were clear i needed a 3 hole , i understand that, just wasnt sure if i could get away with it the way it is being that its over not under specs. Thnx
 
Will it run? Probably. Will it run like shit? Most definitely. Tolerances are there for a reason, but you could always engineer your own engine from scratch and have whatever squish you want. The thing you need to realize is that you are wasting our time saying after we give the specs that I know it's not right but will it be ok. You originally acted as if you had no clue what the specs are. The way you conduct yourself on here will determine the amount of assistance you receive. Technically no one has to help you with anything.......

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Your engine will run just fine, most people would never ever notice any difference. Sbt builds all their engines with a 5 hole gasket. So that tells me they might not even check it. Your ski will not run bad at all. It would probably run just fine as it is, but I would switch to a 3 hole.

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Your engine will run just fine, most people would never ever notice any difference. Sbt builds all their engines with a 5 hole gasket. So that tells me they might not even check it. Your ski will not run bad at all. It would probably run just fine as it is, but I would switch to a 3 hole.

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Thank you. Again , your info is appreciated.
 
Will it run? Probably. Will it run like shit? Most definitely. Tolerances are there for a reason, but you could always engineer your own engine from scratch and have whatever squish you want. The thing you need to realize is that you are wasting our time saying after we give the specs that I know it's not right but will it be ok. You originally acted as if you had no clue what the specs are. The way you conduct yourself on here will determine the amount of assistance you receive. Technically no one has to help you with anything.......

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my reason for interrogating further was to solicit an educated indepth answer for the sake of truly understanding beyond specs and yes /no answers. my machine is out of spec and i dont want to tear it apart again to change gasket if not ABSOLUTELY necessary and apparently its not. If this bothers you then so be it . obviously racerxxx gets it. Have a good day.:cheers:
 
Thanks every one for all the help through this rebuild. :thumbsup:All assembled and fired right up. sounds smooth. Ill put in the water next week
 
did you check compression? I'm curious to see what that sort of tolerance yeilds on the compression gauge.
 
Your engine will run just fine, most people would never ever notice any difference. Sbt builds all their engines with a 5 hole gasket. So that tells me they might not even check it. Your ski will not run bad at all. It would probably run just fine as it is, but I would switch to a 3 hole.

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HELP!!! Why would the front combustion chamber be getting water in it. Not the back front ONLY?
 
Bad head gasket o ring?

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Checked it first. New. took heads off and they look fine. edited . i figured it out. hose with water flow regulator valve goes to the left side.
 
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You're supposed to put 518 in the groove at the top of the cylinder.

uploadfromtaptalk1441401541590.jpg

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