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How:To - Checking And Setting The Squish <--in 3D + actual Pictures

19K views 26 replies 8 participants last post by  stealthc9 
#1 ·
So, welcome to the first C.P.S.S. sponsored, support bulletin <--fancy name for a sticky.

Here is the intro post, more to come tomorrow (I swear!)



Checking the Squish, used for any 2-stroke pocket bike engine.

I will be animating it, and our team of experts (you guys) *including the moderators* we are all just PBP "users" Can and (hopefully) will help us spot any errors, or anything that is not "Clear" enough, If you are not able to post in this exact section, it's ok, post in the general section Or pm any of the staff, and we will make the changes over here.

All the posts will be Readable by EVERYONE, For FREE!

Nick.
 

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#2 ·
re: How:To - Checking And Setting The Squish <--in 3D + actual Pictures

Let the river flow! Open source I tell you (For now, not forever) but you had *better* link back to this page, or I WILL be SAD! :confused:

hahaha ask any questions in the main "general" section.

Long Live Pocket Bike Planet! Pocket Bike Forum

Thanks for the "ribbing" I need some motivation sometimes.
 
#3 ·
re: How:To - Checking And Setting The Squish <--in 3D + actual Pictures

Pictures for now, words a little later!

Nick.

Picture 1, the Dellorto SHA 14/14mm (China Clone) Carburetor, it wants to come off, the C1's are a tight fit, and that way you don't even have to take the carb apart, just get it off of the engine. <---Might not be needed!

Picture 2, the "release" screw (Bolt) to let the carb slide right off the Intake Manifold, unscrew it a half or a full turn, then twist the carb back and forth while pulling back.

Picture 3, The intake manifold on the MT-A4 (C1) is held on by 4 silly little bolts, remove them and then remove the intake manifold along with the reeds, (Picture 5)

Picture 4, Where the reed block sits, we will take a look at case modifications real soon!

Picture 5, the intake manifold, and the reed-block (with a ghetto spacer) and the Black Widow "Triple Stage" haha reeds! great on low end and mid power, but no gain on RPM's for me!

Picture 6, The carburetor, still connected to the throttle, and the fuel tank! YES!!!!!

Picture 7, Water cooled bikes, need to at least have the water level drained to a point where it is lower than the level of the top of the "head" unless you like a rusty engine, and coolant all over the place.

Picture 8 +9 +10, I don't know, you guess what is happening there! haha

Notice the Silver upgraded Banshee radiator, this silver radiator is now usually standard on most all water cooled C1's

Next....
 

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#4 ·
re: Checking And Setting The Squish <--in 3D + actual Pictures

Continued...

The engine has landed, the top engine mount was already broken (I swear) so that was easy, then one long bolt with a spacer on the right side, for the rear engine mount.

Grab a spark plug socket, and a ratchet, a wrench or pliers work too, I know, I am a crazy engine scientist <--not really, it's like a $3 socket!

Now remove the spark plug! <--be careful you aren't just spinning the the "head dome" <--loosen the head after the spark plug is out!

Ok, done here!

Next.....
 

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#5 ·
re: Checking And Setting The Squish <--in 3D + actual Pictures

Even more!

Pictures 1 and 2, a dirty, classically "Fouled" spark plug, I told mike how to mix the oil, he was probably doing something else at the time.

Picture 3, looking into the cylinder, the piston is right in there, almost at TDC <--Top Dead Center

Picture 4, the 1.5mm solder (it's old, I'm sorry) I like to use 1.5mm because if the "Squish" is larger than 1.5mm there is likely more work to be done (skimming the bottom of the barrel) <---coming soon! use something soft, and hopefully not rosin core! haha.

Picture 5 + 6, The 1.5mm solder is actually 1.4mm Or my super duper Harbor freight calipers are off!

Picture 7, the straight piece of solder, 6 - 8 inches maybe.

Picture 8 + 9, The L shaped 90 degree bend, so we can, get over to the squish band, and "cover" the piston pin. should also flip the solder and do it at 180 degrees too, so we can assess the pitston + crank + pins + bearings.

Picture 10, The "Squish Setting OEM Tool" hahaha in the cylinder, hold it there by hand the whole time!


Next....
 

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#6 ·
re: Checking And Setting The Squish <--in 3D + actual Pictures

hahaha almost there!

Squish was 1.3mm ahahahah hahaha aahahha hahaha

Picture 1, With the solder in the cylinder, rotate the Engine back and forth past TDC a few times slowly, to squish the solder. measured the squish, but had a license plate in the shot, I'll crop it and add it again, but 1.3mm is REALLY BAD!!!!!!!!!!!!!!!!!! I mean it!!!!!!!!! Seriously!!!!!! Not GOOD!!!!!!

Picture 2, Remove the bolts securing the head to the top of the cylinder, and remove it.

Picture 3, Hope that when you turn it over, you dont find some wax or pond scum or whatever the hell that blob of junk is in there! Grease I think hahah

Picture 4, it's in the water passages of the cylinder, I wonder if this made the bike run a little hot? eheheh

Picture 5, the "usual suspect" the dreaded "Double Base Gasket" hahahah

Lets move ahead! <-- you can stop to smell the roses (other pictures) if you want or need.

Next....
 

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#7 ·
re: Checking And Setting The Squish <--in 3D + actual Pictures

Getting Closer!

The hammer is a JOKE! <---do not use sledge hammers on 50cc engines.

Only (1) Piston ring, but they took the "Time" haha to add two base gaskets <--- top shelve work, not really, I knew I saw a C1 with one stinking ring somewhere, hahaha! <--sorry Cam, you are still right, sometimes more is more, go for the 2 ring pistons you guys!

Picture 2, Using anything that wont do too much damage, a handle of the socket / ratchet, I think SO! just about half way up the header, not all the way to the piston / cylinder, GENTLY pry it off, the base gaskets usually have some liquid gasket maker on them, so taking it apart might be tricky, just go slow, and dont tilt the cylinder sideways too much!

Picture 3, hahahahahah do not do this!

Picture 4 + 5, Yes! it's loose, set it right back in place and rotate the engine to BDC <--Bottom Dead Center then lift the cylinder all the way off of the piston while holding the flywheel or clutch so the engine doesn't just spin, again, straight up and off, slowly, and gently, but dont trip, if something does snap, it's going to be a cheap little piston ring! <--$5 haha Even I can afford that!

Picture 6 + 7, It is fine to leave the "Bottom end" just like this until we come back together!

Picture 8 + 9 + 10, Hmm, that base gasket looks awful thick, lets take a look... well what do you know, it's not a base gasket, it's Twins! ahahah I think I am able to guess why the squish was so high! how about you?

Next.
 

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#8 ·
re: Checking And Setting The Squish <--in 3D + actual Pictures

It's all down hill from here!


Picture 1 + 2 + 3 Remove the 2nd haha base gasket, and measure it, time for some "engine Builder" Math, hahaha

well 0.7mm single gasket thickness, 0.7mm + 0.7mm = 1.4mm, whew, even I can crunch those numbers, well, there's your problem <--MythBusters again! Sorry!

Picture 7 + 8 + 9 + 10, the orientation of the piston ring gap needs to align with the small Dowel (Pin) so it is locked in place and can not, i repeat NOT spin freely, pinch one at a time (supposed to be two) and gently edge it back into the cylinder, <--add some oil to the piston / cylinder for this part <--sliding the piston back inside the cylinder.

Next.
 

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#9 ·
re: How:To - Checking And Setting The Squish <--in 3D + actual Pictures

YES!!!!! SO CLOSE I Can Taste IT!

Picture 1 + 2 + 3, Return the Cylinder to it's full "upright" position <---Delta? haha and secure it using the four bolts, finger tight, then just tight enough to get the cylinder back down, all the way down!!!

Picture 5, Now you can see where the squish tool haha sits while it's being squished, you could even use a bit of tape to hold it in place, but, don't add tape for the far end, or it will make your measurements become larger.

Picture 6 + 7, with the solder in place and the head all the way back on, rotate the engine some more to "squish" a new section of solder.

Picture 8 + 9, Measure the newly squished solder, yummie, 0.8mm was really 0.7 after a 2nd look!

So, put that sucker back together, toss in a new spark plug, check anything else needed, mount it back in the bike, (it could have stayed mounted by the bottom, but anything worth doing is worth doing WELL!

Done, Somebody want to do the real math and tell me the compression ratio before and after the "Fixed" squish setup? <-- it's a good test for someone who likes math! Otherwise I have some software that can tell us!

Squish sizes .5mm is perfect for a monster, .6mm is almost as good, and .7mm will last longer and start easier, but have a little lower compression ratio, race fuel is not needed!
 

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#10 ·
re: Checking And Setting The Squish <--in 3D + actual Pictures

And there you have it folks, from WAY too BIG (1.3 or 1.4mm) to 0.7mm by removing an "Extra" base gasket, NO MACHINING, What you see is what happened, one hour total, minus another 20 minutes (to get the engine back in and mounted!)

But remember, those base gaskets come in lots of different thicknesses, so measure twice!

Now, what shall we shatter next? <---Pm me! it's all easy for me, lets make it the same way for you guys too!

Now, go set those squishes my lovely PBP members! <---Take pictures! PLEASE, I did it, you can too!

:thumbsup: :p:thumbsup:
 
#12 ·
re: Checking And Setting The Squish <--in 3D + actual Pictures

Thank you john! You say you are a trained Chimp, well buddy, get ready to evolve!

Don't get me wrong, 2005 - 2011 (working on auto diesel and motorcycle engines) is not what makes me an expert, my time @ PocketbikePlanet + two tech degree's (almost) and an unquenchable thirst for knowledge, coupled with a love of Helping out, and an understanding of the frustration involved with learning DOES! (I have a bit of dyslexia) <--thanks mom hahaha just kidding! so needless to say math tests are NOT fun! :eek:

No Animator I have ever met, and no mechanic I have ever met, can do both things better than me, are there better artists? YES, are there WAY better mechanics YES! There are some right here on this forum! :D (StrayDawg "Brady" .... I remember you gave me some of the first help I ever got on here!) <---Thank you! even if it's 6 years late!

This forum is going to make other forums sad, maybe we will branch out and do a dirt bike section, or a full size bike section, but one thing is "For Sure"

Check back often, and save those dollars $$$ for parts for a silly little bike that is the most fun on earth!

I am arranging things so I get to work right out of the house (mostly) <--means I'm almost always within "Ear-Shot" of users needing help! and I have usually two or three hours a day to do fun things to help you guys out, plus, the orange bike is a birthday present for a friend of 15+ years! so it was going to happen anyhow, all I had to do was snap some pictures.

Thanks again, for being a user, for asking questions, for inspiring me, and for already helping out so much!

Time to add 10x this much text to all those pretty pictures.
 
#14 ·
re: How:To - Checking And Setting The Squish <--in 3D + actual Pictures

where's the video? jk haha! Great job nick, most detailed how to i've seen of this type.


Hugh
SDscooters

ps 1 ring = extra rpm's
Thank you Hugh, but RPM's are all but meaningless when "Blow-By" is most likely happening.

Unless you like 22,000rpm screamers that make 2hp!

:thumbsup::D:thumbsup:

Videos will be here soon, but, I need some "Motivation" ehehe...
 
#18 ·
re: How:To - Checking And Setting The Squish <--in 3D + actual Pictures

Wow, 50 views per day? x 2 days = 100 views!

I guess I'll do some more tomorrow! thanks for checking it out guys!

Nick. :thumbsup::D:thumbsup:
 
#19 ·
ahhhhhhh :eek:

"tomorrow" never got her yet!

2 short term, and one (hopefully) new long term job are taking up too much of my "Free" time!

Join the clubPBP and I will "Quit" one of the "other" jobs (just for YOU!)

Nicky. :p:thumbsup:
 
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