Compression numbers

Zach Zaletel /

Can anyone tell me what psi I should expect to see on my compression gauge when testing a Sachs 505 engine?

Thanks - Z

Re: Compression numbers

Don Pflueger /

all two strokes need 120 or higher to run correctly.

Re: Compression numbers

Zach Zaletel /

Thanks Don

Re: Compression numbers

Steamboat Aka J. R. Stevens /

Hey Donp, My Honda 50cc 4stroke book calls for 160 to 180 PSI. Why is there such a difference? Is more PSI good or bad? Thanks Jim.

Re: Compression numbers

I guess more PSI is good to a certain point?? I think the more compression the better!

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Don Pflueger /

more is better to a point. 120 is the cutoff point i use in my shop.

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Thats what i thought... 120-140 is really good compression. When i'm at ikes next i'm gonna check my compression with my milled down head on my tomos bullet

Re: Compression numbers

It won't be really high, on thate A-3, Street. Believe it or not. I had a head that was shaved .030" and mine had 150 lbs. I thought it would be more. But hey, stock compression ratio is 8.5:1. They were originally designed to run on 86 octane gas.

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Should i be runnin 93... i believe it's pinging pretty bad but my dad thinks it would be fine without the premium... i think he's wrong. What do you think?

Re: Compression numbers

Unlike on a 4-stroke, compression pressure on a 2-stroke doesn't begin to build until the piston rises high enough to close off the exhaust port...

You can calculate expected pressure if you know the exhaust port duration in degrees (and some Calculus) and the compression ratio.. or you can just measure them directly and do the math and forget about the calculus.

the calculation should turn out to be like Don says..

Re: Compression numbers

I run 93, just to be safe. Today I turned 18, so I took my first ride without a helmet. My motor makes more noises than I could ever hear with that helmet. It almost scares me now. It pings, vibrates, makes high pitched sounds (bearings?), and jeesh. I am going to run it until the wheels fall off. I just did a bunch of work to get it running good, so I'll see what it does. I think some of it could be the crankshaft bearings. Some more "noises" could be the rings. The vibrating sound is the front fender. I tore my front end apart and cleaned out the forks. I had to remove it in order to tear the forks apart. The Tomos is starting to scare me. Oh well, I've fixed it before; It can be fixed again! I am going to run it until the wheels fall off.

Re: Compression numbers

wow.. happy b/day!

But be careful.. or you are gonna learn so much mechanical stuff that all you'll be fit for is a mechanics job.. and then you're gonna bust your ass all day and come home covered in grease every night for the rest of your life..

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Don Pflueger /

yeah, like i used to do. then i bought coveralls and work shirts. now only my hands get dirty.

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Thanks Brock.... btw: those old motors made lots of unheard or un noticed noises.

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Don Pflueger /

man i must be deaf. my a3's and a3n's were/are quiet. my a3n right now is quiet and smooth as can be. of course i went thru the entire engine from top to bottom too. but still. my a35 on the other hand is a growling noisy piece of junk. so if i come across an a3n, a swap will be done.

Brock, I'd wear the helmet!

You're 18? Congrats,Man! My turning 18 just brought me closer to being drafted.......LOL!

Seriously, think about wearing at least a half-shell helmet.

You hit a curb or the pavement or a car with your skull unprotected,and the 60+ years of life ahead could be ruined or gone. Think about it, while you still can. don-ohio (:^D

Re: Brock, I'd wear the helmet!

Don Pflueger /

especially where he lives. lol. people from up here get lost going there to pick up bikes they bought from brock and probablt run a lot of red lights and stuff. or should i say run THAT red light? lol you just never know when your gonna need it.

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"all you’ll be fit for is a mechanics job.. and then you’re gonna bust your ass all day and come home covered in grease every night for the rest of your life.."

zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz

Hmmmm!

I was a mechanic ( Field Tech) for IBM for 30+ years, and I don't remember ever coming home covered in grease.

Are you perhaps being a bit elitist?

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heh .. reminds me of one time i was under my brother's car changing the oil. He has zero mechanical ability. I'm done and came out and there's just a smidge of oil on my hands.

He's standing next to his girlfriend and says "wow.. you didn't get very dirty... just a little bit."

I says "you gotta be a some kinda freakin genius to change your cars oil without getting dirty at all..."

As i'm walking away, out of the corner of my eye i see them turn to each other and smile real wide.

Re: Brock, I'd wear the helmet!

Lmao... you guys are _______! No word can describe. Yeah, DonP kinda got lost in New Philadelphia, and then some. I don't know about my motor, I think it is all kinds of stuff making noises. Probably just beacuse I ran the balls off of it for the last year. And because of how long it had been sitting. To go from 20+ years at a stop, to running every day it possibly could, and wide open 95% of its time, must be hard on a motor. It used to be smooth like glass. Now, it (My Tomos) is like an old race car: it saw its prime, it still will run, but it is tired, can't keep up with all the new technology. It is something that I want to leave to my kids, if I have any. I may already have a job at a truck dealer here in Midvale, working on forklifts. My instructor is working on it for me. I am finally getting my car license, even though I'll still drive a moped more than a car. Another point: LOOK AT THE DAMN GAS PRICES!!! They fricken sky-rocketed!! My friends call me "immature" for my moped. I laugh at them when they complain about the gas prices. I tell them all, "Ahh.. nothing like puttin' a couple bucks in the tank, drivin around for about a week or 2, then puttin about 2 bucks in it... I get about 100 miles to the gallon, oh and my insurance is real cheap, because I don't have to have any!" My one friend today at school asked me if I was "still on that moped kick?" I told him, "I never quit mopeds!" I have some MRA apparel, and a homemade Tomos shirt, so my second name is "moped" or "Tomos." Thanks guys, for wishing me happy birthday. I hope this year to meet a bunch of you, at some of the Moped Army functions, or the races. I don't know if I want to wear a helmet or not. Peace out.

Re: Brock, I'd wear the helmet!

Wear it whether you want to or not..................the first crash you have you'll thank yourself for listening. don-ohio

Re: Brock, I'd wear the helmet!

I hope the first crash is the last. I don't think I could live with the fact my Tomos is mashed up. I'd rather be gone, just like it would be.

Re: Brock, I'd wear the helmet!

Brock........don't think like that..........they'll make MORE Tomos' mopeds.

You said you got `saved'? Then follow the Bible's advice to think very little of worldly possessions and much more about your health and safety. don-ohio (:^D

Re: Brock, I'd wear the helmet!

Yes, you are right. But, if its my time to go, its my time to go.

Re: Brock, I'd wear the helmet!

I hate to disagree with you all the time, Brock, but `fatalism' is not true at all. It's just been used as an excuse for people to do what they want,when they want. don-ohio (:^)

Re: Brock, I'd wear the helmet!

Ok; I ride safe, use my signals, look before passing (when I can). I like to ride in groups, but my buddies I ride with don't have the balls to ride in the cold. I just had a bad last 18 years, I don't know how my future will turn out. I just trust God, let him be the light guiding my way. I will take advice from you guys, you've been here longer than I. Thanks Don-O.

Re: Brock, I'd wear the helmet!

Brock,

I do understand what you're going through as I went through abuse myself, and my life was pure hell the first 16 yeras of my life. With all due respect, "turning to jesus" will not really solve the problem.

It only will bring an excuse for you to hide your pain and put it away. It'll haunt you for the rest of your life...

I used to be a bad mother. When I say "bad", I mean bad. I got kicked out of 7 schools and whenever anybody tried to make fun of me because of my deafness, they found themselves in the hospital in critical condition.

But, it all changed literally overnight. I kicked my dad's ass, and badly. I nearly killed him... I broke his nose, broke his ribs, gave him a black eye, and broke his left elbow and his left pinkie finger as well as the finger next to it. And it only took me 5 minutes to do it...

Immediately the day after I did this to my dad, I went back to school as an A+ student, became president of the student council for 3 consecutive years, and I did a lot of good things for the community.. And it felt damn good.

That's what your dad needs... Wait until he's sleeping and a baseball bat will do. That'll beat being saved by Jesus anytime, trust me on that one.

EK

Re: Brock, I'd wear the helmet!

No... I'm afarid I can't do that. I finally got out of there. I'm not going back. I still love my dad. He taught me a lot. I wouldn't know anything about mechanics if it weren't for him. In every bad, there is always good. I love everyone, like Jesus did. You should give it a try. Just trust him. Read his word (the Bible) sometime. Now that you are older, you may be able to understand it. Ask someone if you don't, I'm sure they would be more than willing to help you.

Re: Brock, I'd wear the helmet!

Brock,

Best of luck to you, man. I'm happy you got out of this situation.

It worked great for me in my case- my dad now is a super dad. What I mean by this is, he has been the most loving father a guy could ever ask- since I kicked his ass.

It's not about violence. It's about getting respect. Men like our fathers only understand respect when they get their ass kicked. And that's what happened.

In my case, my father has never touched me. And in addition to that, I have a 16 year old brother. My father never ever touched him either. (I told him I would kill him if he did.)

And my brother has been living the dream that I never had. My dad does everything he can for him, and he makes sure he gets the clothes he needs, the education he needs, etc. He never did that for me, at least not until after I kicked his ass. He then did the same for my younger brother and my younger sister.

Anyway, I know it's a difficult situation. When I was 15 and younger, I was afraid of nobody... Except my dad. He seemed so big to me. So powerful. He seemed like someone that could easily kill me. I wasn't scared of men much bigger and much stronger than my dad. Only my dad. He seemed bigger than them all.

Brock, my father taught me a lot about woodworking, mechanics, and stuff like that... But that was NO excuse for abuse! And it is not reason enough for love to be given to him by you. I made my dad earn my love. I refused to talk to him for 2 years and called him "Piece of Shit Kevin" right to his face.

Now, I am 3 times the size of my dad (I worked out like a maniac & ate like a maniac for 6 years in order to kick his ass.) And I tower over him as well. Today, he's just a small old man that can not possibly do anything to me.

And you know what? It feels good. He know's "who's the daddy" now. And that's me.

You know, despite my anger about this situation, I am actually well balanced in real life. I'm a dormitory supervisor for elementary & high school boys-- and I do very well. I'm going to be married soon, and I have a baby on the way. Life's really good.

But I will never forget what my father did to me. And that's what I will remember when raising the baby. The cycle stops with my father. I am so much against the idea of abuse that I do not even believe in spanking. If there is any spanking to be done in the house, my fiancee is going to be the one to do it. Not me.

In your case, you may carry it until you break the cycle. You may do the same to your children if you don't do something now to satisify your emotions. Jesus ain't gonna do it. It's only going to hide it. Priests molest children. That's evidence enough for me.

Best wishes for you, Brock. I hope the situation gets better for you. Kudos to you for getting away. That's the first step. You have many more steps ahead of you.

The next step now is if you ever want a relationship with him ever again... You'll have to make him earn for your respect. If kicking his ass isn't an option, you'll have to find another way.

EK

Re: Brock, I'd wear the helmet!

Brock,

P.S. I was saved too. It did diddly squat for me. I still haven't seen no Jesus.

EK

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