Well........

[fastbanshee199]

I tried figuring this out basically on my own with getting it ready. The plugs looked good, i did a leak down test today and i never saw any leaks, ANYWHERE. I had a little help from Meat but that was it. This was my first top end rebuild on the quad and it's a 2002. I did 3 heat cycles on the bike, checked torque on all fasteners, rode it for no more then 3 miles and........... well ill let the pics explain the rest.

 

[jbooker82]

Those bolts on the sides of the cylinders will drain the coolant out. That way you don't get any in the crank case when you pull the head or jugs.

 

Were the ports chamfered? Did you check the ring gap?

[jbooker82]

When you did the top end did you bore it or just a hone job with same size pistons and rings?

[Screaming Yellow Zonker]

looks like a little problem there... did you have an air leak?

[fastbanshee199]

Those bolts on the sides of the cylinders will drain the coolant out. That way you don't get any in the crank case when you pull the head or jugs.

 

Yeah i know but im gonna have HJR tear then engine down because im scared something might of went down below

 

Were the ports chamfered? Did you check the ring gap?

I didnt bother removing those bolts because im gonna pull the motor and send to kevin at hjr to check the crank and rods.Im not sure if the ports were chamfered, i took the cylinders to Ratv here in phoenix to bore and hone them. I checked ring gap to what wiseco specified on the sheet and they all looked good

 

When you did the top end did you bore it or just a hone job with same size pistons and rings?

I had the cylinders bored and honed and they told me it was only the next size up and that they looked really good

 

looks like a little problem there... did you have an air leak?

I did do a leak down and never saw any leaks. I left it pressurized for around 10 mins and stayed the same the whole time so i figured it was good.

 

 

Does anyone know what could of caused this?

Edited November 21, 2009 by fastbanshee199

[fastbanshee199]

I didnt have time for HJR to do the work otherwise i would have kevin do it. Now i really wish i had just waited and canceled the trip and him do the work. IF this is a bore/hone error, is there anyway to prove it? Also im not sure this is normal but the side that has the burnt piston, on the dome its black and has some really sticky residue on it?

Edited November 21, 2009 by fastbanshee199

[Meat]

Oh nooooo ! I'm curious to know how it happened. Get some better, clearer pictures of the mess when you tear it down.

 

Here's the fastB199's thread in the jetting forum that I replied to http://bansheehq.com/forums/index.php?showtopic=123793

 

His jetting specs seem fine and he says the plugs were a dark chocolate color. Its hard to tell from the pictures but the piston doesnt look melted, it kinda looks like a production flaw in the piston. Correct me if I'm wrong, but if it ran too hot and melted, would the melting happen either at the center of the piston dome or right above the exhaust port ? The damage is not at either of these positions on the piston.

 

I would like to hear, in detail, how you performed the break-in. How many RPM's did you rev it, how many heat cycles, how long each heat cycle was, when did you ride it, how far on the throttle you had it, any the details you can give about your break-in would help us determine if the damage was done because of the break-in procedure.

 

I'm curious to see the chamfer on the port too. Could it have possibly caught a ring on a port to cause that damage ? The piston kinda looks more like it broke and not so much that it melted.

[vulvafan537240]

Oh nooooo ! I'm curious to know how it happened. Get some better, clearer pictures of the mess when you tear it down.

 

Here's the fastB199's thread in the jetting forum that I replied to http://bansheehq.com...howtopic=123793

 

His jetting specs seem fine and he says the plugs were a dark chocolate color. Its hard to tell from the pictures but the piston doesnt look melted, it kinda looks like a production flaw in the piston. Correct me if I'm wrong, but if it ran too hot and melted, would the melting happen either at the center of the piston dome or right above the exhaust port ? The damage is not at either of these positions on the piston.

 

I would like to hear, in detail, how you performed the break-in. How many RPM's did you rev it, how many heat cycles, how long each heat cycle was, when did you ride it, how far on the throttle you had it, any the details you can give about your break-in would help us determine if the damage was done because of the break-in procedure.

 

I'm curious to see the chamfer on the port too. Could it have possibly caught a ring on a port to cause that damage ? The piston kinda looks more like it broke and not so much that it melted.

 

this is what my piston looked like when it melted. his does kinda look more like it broke though.

[Screaming Yellow Zonker]

I'm with meat... it does look like it broke. (after taking another look). It is right where the port is. did you happen to find any little pieces? Maybe inside the exhaust or below the piston?

[fastbanshee199]

Oh nooooo ! I'm curious to know how it happened. Get some better, clearer pictures of the mess when you tear it down.

 

Here's the fastB199's thread in the jetting forum that I replied to http://bansheehq.com/forums/index.php?showtopic=123793

 

His jetting specs seem fine and he says the plugs were a dark chocolate color. Its hard to tell from the pictures but the piston doesnt look melted, it kinda looks like a production flaw in the piston. Correct me if I'm wrong, but if it ran too hot and melted, would the melting happen either at the center of the piston dome or right above the exhaust port ? The damage is not at either of these positions on the piston.

 

I would like to hear, in detail, how you performed the break-in. How many RPM's did you rev it, how many heat cycles, how long each heat cycle was, when did you ride it, how far on the throttle you had it, any the details you can give about your break-in would help us determine if the damage was done because of the break-in procedure.

 

I'm curious to see the chamfer on the port too. Could it have possibly caught a ring on a port to cause that damage ? The piston kinda looks more like it broke and not so much that it melted.

I did a total of four heat cycles first one was in garage until it got up to temp and then let it cool off completely. all ran for 15 min AFTER is up to normal operating temperature and then i would let it cool completely after each time. First was just idling and lightly blipping the throttle no more than 1/4 every time. i adjust limiter at top of throttle housing so i didnt go over.

Second. i rode it only till 1/4 throttle varying it .

Third. rode it up to 1/2 throttle varying it

Forth. rode it all the way up to 3/4 throttle

I never left it pinned for more then 2-3 seconds

I pulled the cylinders off late last night and i will remove the pistons today clean them with parts cleaner and take some more pics

 

I'm with meat... it does look like it broke. (after taking another look). It is right where the port is. did you happen to find any little pieces? Maybe inside the exhaust or below the piston?

I havent found any pieces anywhere. the oil however that was in there was a pretty dark grey color. hopefully i can afford to have kevin take the engine apart and check everything and i may have him just do a 4 mill 68 bore kit and some port work. ill know on monday when i can call and get some prices

[AKheathen]

well.......there is a couple things that i can see....first, it does look like a detonation induced break of the ring land, which i have seen before in a case of spark scatter (had a distrobutor issue) but, the thing is that it is mostly broke @ the exhaust port, plus that little chip in the transfer. the piston appears a little frosted, which indicates thaat the crown was running a little hot. next, is the cylinder bore. it looks like you may have a bit of excessive clearance, and they are glazed/scored pretty good for a break-in. 2 things to check out. the piston clearance by using a bore mic, and caliper mic. and the port chamfers. if you can show both the clearance and lack of port chamfer, you may just have a case for judge judy, lol get some better pics please.

[fastbanshee199]

well.......there is a couple things that i can see....first, it does look like a detonation induced break of the ring land, which i have seen before in a case of spark scatter (had a distrobutor issue) but, the thing is that it is mostly broke @ the exhaust port, plus that little chip in the transfer. the piston appears a little frosted, which indicates thaat the crown was running a little hot. next, is the cylinder bore. it looks like you may have a bit of excessive clearance, and they are glazed/scored pretty good for a break-in. 2 things to check out. the piston clearance by using a bore mic, and caliper mic. and the port chamfers. if you can show both the clearance and lack of port chamfer, you may just have a case for judge judy, lol get some better pics please.

 

 

**UPDATE***

 

I called and spoke to the owner at RATV. They basically bored and honed my cylinders again and gave me a new top end kit. Apparently i should of been running atleast 310's for mains if not 320's. So i just got done putting everything back together again and its running but it seems to only be running on the right side now. Both have 125 psi of compression on the cylinders. the right side pipe gets hot and at normal temp, the left side stays cold. i checked the plugs ( by the way it has 320 mains in it right now) and the right side was pretty dark and left side looks like it only fired a couple times ( the plug is still white with a very small spot where i think it fired a few times) and is wet. there is also fuel/oil IN the left side pipe as well. I verified spark. now im stuck yet again i dont understand why is wouldnt fire on that side. and again leak down confirmed no air leaks.

[AKheathen]

are you leaking any fuel out of the left carb? iss th left pipe plugged up? are you getting good blue spark on the left?

[fastbanshee199]

are you leaking any fuel out of the left carb? iss th left pipe plugged up? are you getting good blue spark on the left?

 

 

Well i figured out why it wasnt running on the left cylinder. It was flooding out with fuel. LOL why do you ask? Well i just rebuilt the carbs and the guy i bought the carb bodies from told me it had 25 pilots in them and i dont need to replace them. THERE WAS NO PILOT JET IN THE LEFT CARB. I put it in and its fine. two top end rebuilds in two days. im running 320 mains right now, third clip, and 25 pilots and its running TITS. i did 3 heat cycles today and rode it for over 60 miles today and no problems so far. plugs are a good brown paper bag color. Thanx for all the help guys!!!!

[Meat]

No pilot jet !! aw man thats crazy, iv never heard that one before but it explains a lot. Well lets hope everything works out for ya now.