The Quadzilla Banshee Quad Is Back! 

Big thanks again to David Midkiff, owner of DM Cycles for doing the boring on my cylinder. If you guys need any work done to your machines call Dave: Phone: 573-883-0203 Email: dmcycles09@yahoo.com Facebook: facebook.com/dmcycles09 Thank you for subscribing and continuously watching my videos! Instagram: 2_vintage_

I have a Cr 500 that I bought in boxes. The cylinder with the bike had been re-sleeved and had been machined at the base too much and had the same problem as you. So I made a 2 mm base plate out of ally sheet ( same shape as gasket) and used 2 base gaskets either side of it. Worked fine and has been on bike 10 years. Also take into consideration that the rod will lengthen with heat and high revs while in use so always best too have more squish than less. Great build, best of luck.

When u ride a big bore 2 stroke anything u short shift it and let it eat. Riding them wound tight is out of the sweet spot in them. 80cc & 125cc u have to stay on the pipe (revved up or wound up) but the bigger ones u get more power from bottom end to low top end.

Glad you had a great experience dealing with the folks at DM Cycles.👍🏼 Good customer service is so important. I just smile seeing you performing tasks a top your sweet work bench.👊🏼

I'm amazed with how much you get done in a video and how often you upload. Your on a mission to fix them all!! Great video, as usual. 🔥💪

I'm a 4stroke engine person myself, but am learning so much about 2stroke engines and just how much the 2stroke engine relies on correct fuel ratio and proportion by watching your amazing videos !! Thankyou

Put the mesh on fuel line Joe, it will help immensely. Great vid, great job!

The beast has been woken, been waiting for this 🤘🏼

I know you'll figure this out, you got this Joe! Another great build from you, can't wait to see this best run again! Awesome job on noticing the piston was going to far I bet the last guy shaved the head an didn't tell you! Add another base gasket an you should be alright!

That's a bummer joe no doubt you will find a good solution to overcome the problem at least you are on the right page mate would be devastating to put all the work into it for it to blow up again good luck and take care 🔧🔧👍👌🔧

I created my own spacer between the crank and cylinder with a sheet of 5052 aluminum 1.5mm thick. Outlined the gasket and cut it out with a dremel. Took about 3 hours to get it done. Used soldier wire to check the head piston clearance. Got it perfect.

No it never had the wrong Rod put in it the reason that you're showing positive deck height is most likely the cylinder has been decked once or twice to reflatten the surfaces and what happens is eventually it will be just enough to touch the head all you need to do is run a thicker base gasket or run a cool head

So nice to see a clean motor getting put together.... Looks good man very professional..

You can adjust the squish by using different thickness base gaskets, or stacking them if you need to. Use sealer between each gasket. Also, When they told you to wash the cylinder in soapy water, they meant actually scrub the cylinder wall with a plastic brush or something similar. Not dunk the parts and call it good. The point is to get any embedded small cast iron particles out of the cylinder wall that's left over from machining. Same for the piston. You should also wipe out the cylinder walls vigorously with automatic transmission fluid and paper towels after its washed with soap and water. The towels will come out with gray iron on them guaranteed. And oil every single part and piece when you assemble them! If it moves it needs oil.

Hope you plan on decking this engine before running. Squish, decking, gasket thickness, head gasket Inner diameter, spark plug gap, fuel to run and oil mix ratio, so many things needs to be figured out by a builder to be able to run this reliably. I own two quadzilla quads and I let my builder figure these things out, and I just follow what they tell me afterwards. Saves me money and keeps my machines running 👌🏼

Ohhhh baby! That cynlder top down shot, yeah boy smoooooth🤘

Assymbly lube on power valve is good idea.great job Joe!

Been waiting for this one

I would try to reach out to Sabo. He'd definitely have answers for you

When you have it bored out two or three sizes bigger sometimes you need to have the head sent out to have the combustion chamber matched to the size of the piston it's not a common thing that happens usually you're all right as long as you don't go major overbore

You're the man brother keep it rocking

Been waiting for this Joseph. Haha thanks for the video

I had the same problem with a 86 kx125, I just used the 2 head gasket method and I have had no problems with it.

Jug is gorgeous, sweet!!

Check squish clearance first. If it’s to small raise the cylinder with a base gasket. But first check the ports at BDC bottom dead center and make sure the piston is just below the exhaust port and just above the intake. You’ll figure it out no biggy

More 2 stroke content 😁😁thanks so much

Double or triple up the cylinder base gasket or use a thicker gasket until it gives you the right amount of clearance I had to do this on a few snowmobiles and 4 wheelers

still make sure you have adequate coolant circulation. your scorched piston is an overheat issue, coolant flow, bore too tight or lean on top end

Helll yeah Joe !!!

It had already been suggested a fair few times, but what I would do is run a base plate that matches the difference in deck height. Maybe it this was missed out when the previous owner built it? Best of luck 👍🏼

That’s why you buy the right tool and check the squish and deck height with the proper guage so you know how thick of a gasket or gaskets you need to use but you should already know that since you build these bikes all the time. That way your not just winging it and hope it doesn’t blow up

you can double up a base gasket which will bring the piston flush with the cylinder top..

Put our jugs in Sonic after machining. Really makes them spakle... lol😅

Rule of thumb every moving part that is metal on metal I always use Lucas break in procedure oil or at least use Lucas assembly lube on all metal to metal moving parts

Double base gaskets to keep piston from coming higher than cylinder and then double for the head clearance. The end

That old gasket has already been banged to shit and self clearances itself

With the piston coming up out of the cyl 2mm as you said it probably has had a stroker crankshaft installed in in it and will require a equally thick spacer under the cyl to keep the piston at the correct height

coolest Banzilla

Great video

several of the The dirffereamce between the top of cylinder and he top of the piston is called the deck height and most of the European bikes of the 70 and 80's were designed to have an adjustable. deck height. they came with several different thickness of base gasket so that you could change the power of the motor by adding or subtracting base gaskets. example: race bikes had very high compression where a trail bike had a little less compression. It made it a little more manageable especially in tight woods. If someone shaved the surface of the center cases because they were a bit warped then that would explain the difference you are seeing. adding an additional base gasket is not that big of a deal but as you have discovered the use of a permatex or such can really help to keep it all together, best of liuck.

Been waiting for this creation to come back! #rocketship

My 1989 LT500RK wasn't like that. But she was a beast and make sure you have those Jets right because that kick start kick back will put your knee right into the handle bars. One time I went to go kick that Zilla put that Kickstart right through the bottom of my boot

I want to add: With the head not overbored to the same diameter as the piston/cylinder the piston crown hits on the outside .020" or so, locks the rings, the stuck rings jam the piston randomly against the cylinder wall depending on forces and scores/melts things.

got a 400ex needing a top end waiting on the videos of the niche 440kit👍

Very very typical not un lucky lol! Should be pretty reliable after a fresh re build

Sometimes you may have to use two base gaskets or have the cylinder squish band cut

Ken O'Connor racing can shave your head definitely or if you can find a stroker spacer plate, if the wrong rod was fitted all the ports will be slightly off I'm sure

I still hope there is no debris in the bottom end, and that the seals weren't the cause, or one of the causes, to your blow-up, or it will just blow up again. The quadzilla has a terrible squish setup OEM. If the squish gap is too large, like OEM, it has a much HIGHER chance of detonating than if it's a little too small. Did you replace those wrist pin thrust washers? Good practice every time the cylinder is off. They like to fracture and make a big mess of things. You don't necessarily NEED the billet aluminum ones and narrower wrist pin bearing, but you should at least buy the ones off the 88-92 LT250R. They have a smaller ID, so they rattle much less on the wrist pin, and that means much less chance of initiating a fracture after some hours of use. Good call on the base gasket pookie, although you didn't have to put it on the exhaust side, just the transfers and boost areas are sufficient. Putting it on the top side of the gasket too will ensure no blowouts. Also, the clutch lever is on upside down. Bigger base fasteners take 29 ft-lbs, the smaller ones take 8.5 ft-lbs. Also, the studs should be put in the cases and head by themselves and tightened, not with the nuts. Did you clock the head gasket correctly? Little holes go over the exhaust port. The head nuts should be tightened to 18 ft-lbs, or the head might warp and cause a coolant leak. 87s are known for this. Bigger head studs don't help, as it's the head that flexes, Not the studs. I thought I saw the piston sticking up past the cylinder. THAT will make the squish gap too small! A non big bore head gasket will hit the piston too. Obviously, someone decked this cylinder way too much at some time. You need to see how the crown of the piston lines up with the floors of the ports. It the piston sticks into the port height wise, you need 1 or more additional base gaskets. If the piston lines up with the floors, you need a non-cut head and/or a thicker head gasket, depending on your squish test. It's not the wrong rod. No other rod would work. The closest rod length wise is the CR500R rod, which is 1mm longer, but too many other things won't let it be used in an LT. If the piston doesn't hit the old head gasket when you turn it over, the new head gasket is not a big bore head gasket. The thickness is not the problem. Measure the ID. The new head gasket is probably less than 88mm, and the old head gasket is more than 88mm. An OEM gasket won't help there. That's one problem solved. But the piston sticking out of the cylinder still needs to be solved The piston must have just touched the head gasket before. How much bigger are the holes in the head gasket than the head studs? If they are big holes compared to the head studs, the gasket must've been off center slightly. You probably shouldn't ride it until it's warmer. Jetting for the cold is a pain. Also, I'm sure the balancer is timed wrong.

Great video, I would of put another base gasket so that the piston dosent go past the top of barrell. KTM.380 comes with 3 base gaskets to get the correct TDC

add a extra base gasket to adjust the clearance

Damn dude that head gasket ordeal… I hope this thing runs

use 2 base gaskets with gasket maker in between them. worked on my dads zilla 500 for years.

You need to ensure the head gasket you have will fit an 88mm bore and not be smaller cause you will have issues...bad issues

Hey just thought you could try getting some custom copper gaskets made for top & bottom of the cylinder? Known people have done this before to get round problems

you have used the thinnest base gasket so your cylinder is sitting lower . increasing your head gasket thickness will alter your squish but mess up your port timing. measure your sqyuish to avoid this. i reckon that has been worked on in the past and is running minimum squish

i'd get an o.e rod and bearings and start there lol i'm putting my money on stretched rod from when it jammed up cuz it full on locked up, if it made enough heat to seize a piston until it cooled off it most deff stretched a rod, not only are you making heat from lean running your making even more heat from friction because lean in a 2 stroke means less lubrication too. it was probly stretching as your were riding and when it jammed up was the final blow it seems to be the obvious culprit. i'd look up stock rod dimentions and measure the one in it or just replace it all together before going bill nye with double gaskets lol. plus when you look at the piston when its above the deck at 26:10 it's not even all the way around, the wrist pin is slightly tweaked look at the piston gaps it's super tight on the right side and looks wider on the left.

Don't forget about the base gasket. It may be safer to put a thicker gasket there. Good luck.

Diameter of head gasket the metal insert could be hitting the piston mic inside bore on all head gaskets

Good morning just watching some of vids today was curious if the a arms on your lt250r are aftermarket or not because they dont look like the arms on my 86 thanks! Keep up the good work!

Bore the combustion chamber diameter in the head to the same overbore diameter as the cylinder/new piston size or the outer edge of the piston will hit the head and lock the rings. The previous owner may not have done this either. I don't know if this is your problem but I've seen it happen on an overbored 2017 yz250 with the exact same problem of locked rings on a new topend. It was hard to notice any damage on the top of the piston if you didn't know it was there. Like I said just another thing to consider.

Sweet

Always use hondabond ht for base gaskets and intakes. Not permatex

I don't think I'd chance it without checking the clearance

You might need to put a fatter base gasket on. See what the ports are like see if the piston matches with the ports may need to raise the whole cylinder

Squish 101, adjust your squish with your base gaskets, there should be different thicknesses in the set?

my ktm 300 came with multiple bottom cyclinder gaskets to do the quench

@2vintage tou should do a garage tour

The piston hitting the head will have caused the ring groves in the piston to close up slightly .maybe what caused the problem in the first place

Check the thickness of the basic gasket some bike have more like my ktm hade 3 basis gaskets

You have to add to the base and recutting the head maybe required but I’m betting you get away without having it cut just add to the base and get your squish to .020 .5mm at minimum

Never seen this problem and I could be way off but maybe a thicker head gasket would make the clearance

When we need work or entertainment we only call 2vintage garage haha jk

You need to add an extra base gasket

Have you looked into the polaris outlaw 525 irs with the ktm moter? And if so would you do one on the channel?

I’d get a new rod.

Build up base gasket till you get clearance

Go to rectification a cilynder head and go 🚀🚀🚀

did u think about a different base gasket

maybe a thicker base gasket?

In my opinion this is why when you rebuild a engine you need to measure everything at this point with the super high compression I'm not shure but it could be a stretched rod I would want to know if when it was rebuild the last time if the rod was replaced? It's hard to tell without a blueprint check list with all the measurements wrote down .

You should get a sled to fix up this winter

hopefully it blows up again!!!!!!

Could it be a stroked motor with a OEM head? I came across a similar situation with a 2 stroke dirt bike years ago. I ended up going through phat head for a custom billet head. The only issue is figuring out the measurement for them to machine the new head. If that's your issue.

4 corner seized. Aka cold seize. Previous owner didn't let it warm up properly before ripping on it.

Make sure to set the timing per service manual.

Hey joe I just picked up a 1991 honda 250x and it's got a dg slip on and I was wondering what I should run for jets beacuse when its warm it idles high but when it's cold it wont idle and you have to hold the gas

You can use other things. I know in auto engines with clearance in bearings and caps they use small pieces of plastic string made for that.

Look man you need to invest in a Snap-On compression tester and a borescope so so you know you have good compression and you know your cylinder walls and your piston are in Tip-Top shape

Just stack some base gaskets till the piston sets flat with the jug should work just fine I built a bit of stuff and never check how tight bolts or anything should be i just eyeball it always works out I mean I seen as soon as you put the jug on you was going to have that problem lol I seen it pop out and went wow not good almost was thinking you was going to blow it up again fr I always check my stuff but just with my eyes lmao but I only do small engines I like to be able to pick up the motor if need no stupid tools or lifts just some riches and time just how I like it

Not your biggest issue but just like the LT your front tires are directionally backwards.

Dang it,

Hey Joe been a minute mate how you going

Crank seals could be bad also causing a lean issue

Metal gasket on the bottom end

You should mix 32:1

What about using molding clay or play dough in like a plastic sandwich bag for the squish test ?

Just finished watching the full video, that’s a strange one dude. Just a thought, can you not get a thicker base gasket? Should lift the cylinder slightly?

Just A suggestion, get out make a copper head gasket and get a thicker base gasket. Not sure if you can use a copper base gasket or not?

@Whoop!

My dad always ran mixed gas in his snowmobile even with the oil injection, he always said he'd rather foul a plug then lose a piston.