YAHOO!! I am not looking forward to doing the top end rebuild, but it shouldnt be hard(my wife is gonna be pissed!). I'm not gonna part this one out duneaddict, sorry. I hope the reeds are still good...$120 is alot to a poor farmer. Where is a good place to buy wiseco pistons? Right now its at .040 over(supposedly). Should I just go to .060?

 

Tear it down first before ordering parts. Let your machine shop mic the cylinder and advise if the bore is needed. Be sure if they bore it they deburr the port edges.
Call Midwest action cycle for your piston kit, they treated me right. I'll send you the phone number in a PM, you can check their ad in any dirtwheels rag.


Website

 

I will. If the quadzilla is anything like the polaris 400 engine, a top end rebuild will be cake. Where is the coolant drain on the zilla, or do I just take the hose off the bottom?

 

hmm, okay... I misunderstood that you might part it out somehow?

The best place to buy Wiseco pistons, is from Wiseco directly... Jump on their website, and/or give 'em a call.
IF it needs bored (Chances are it will depending on the hours since the last rebuild)
The piston to cylinder clearance needs to be pretty darn close, (.050"-.065" depending on what your running for a piston) so just buying a piston and slapping it in is NOT the way to do it.

If you have to send the cylinder out to be bored/honed... Send it to LRD.. they do awesome work for a reasonable price, and get it back to you promptly. They'll chamfer the port edges too (truckracers comment)
You can also buy the piston from them if you'd like. The machine shop needs to have the piston in hand in order to bore/hone to the correct dimensions. (They can also do piston mods/ceramic coatings, etc, etc.)

Personally, I wouldn't go any smaller than 80 over on the piston size. That's the smallest size the Wiseco pro-lite piston comes in... With some mods, they are actually lighter than the stock piston (Lighter=quicker rev)
You're wife will not be happy, because this will take a little Ca-ching to get done right...
I just saw your post regarding coolant drain... There isn't one.. pull the hose off and have a bucket under it to catch the A/F..
Go and get yourself a Genuine Suzuki Service Manual before you do ANYTHING else!!!!! That will be your bible! Live by it, and you'll be fine.
Just my $.02

PinHead: You need to buy/build a leak-down tester! This is the ONLY way to test the integrity of the bottom end/assembly for leaks... not starting fluid.
If the bottom end is leaking... it's going to lean out and KaBoom!! There is no other way to test the crank seals etc. when the motor is assembled.

good luck!

 

Duneaddict, I was just pissed at it. There is a guy here that does a great job boring(had him do my 650 prairie). I am gona tell him to get it so tight that I curse his name when I try to put the piston back in the sleeve.

 

I got the top end off. Looks like the guy I bought it from lied. No DR cylinder work, no v-force reeds. Reeds look stock to me(plastic, pyramid shaped). Shoulda kept the mossbarger reeds. Rings dont look toooo bad, but piston has some scoring on the side. I am gonna take it to the mechanic now.

 

I found where it says Paul Turner, eliminator porting. Has some other junk(numbers) on there. the bore is 86.86mm right now and the piston is 1mm overbore. I am gonna go with a 1.50mm. Looks as if the previous owner ran it with a dirty filter. What size piston should I go with?

 

Gotmuddy, why do you think that roll starting an engine is hard on it?

Using 87-octane fuel in a Quadzilla is asking for trouble. Use 91 octane minimum (mixing with race fuel is even better). This goes for stock motors as well as modified. The 500's piston is large so detonation is a real possibility without good fuel. Also, stay away from fuel with methanol (big reason for burn-downs with 2-stroke sleds).

Never run a motor that you know has low compression. If the piston to cylinder clearance gets too sloppy, you will catch a ring in a port. In other words, when you use an engine with a known problem, you are only creating more problems. You could go from only needing a set of rings, to also needing a new piston, a refreshed bore, or even a whole new cylinder if the scoring is extra deep or if you are out of over-bores.

 

I am just running what it came with. I am going to get the next size up piston .060(1.5mm) and have it bored. The intake side is a little nasty. Will boring it screw my porting up?

On pull starting it....people BITCHED at me about it. I didn't think it made a damn bit of difference, I mean, thats how they start race bikes.

Another thing, I am going from a 59cc dome to a 55cc dome on my powerhead, will it make much difference? The mechanic I took the sleeve too said I might have to have my head cut so the piston doesnt hit it, I dunno about that...he races motorcross. He was working on a kx80, that piston looked like a midget next to the LT's. [img]i/expressions/face-icon-small-happy.gif[/img]

 

You need VERY good, straight race fuel with a 55cc dome! I have the 59 and was told by my engine builder to run 104-octane minimum and to run 100 minimum by CT racing. The compression with the 59 is only around 125-130 but since the big LT likes to explode fuel rather than burn it, high-octane fuel is needed.

Boring does not screw up porting but well chamfered ports are even more important with the larger-than-stock windows. This isn't something you have to worry about as long as you have a machinist with a good amount of 2-stroke boring experience do the work. Don't go with the cheapest guy!