warbags Posted April 10, 2007 Report Share Posted April 10, 2007 Ok i just spent a grand getting a new top end on my shee,i broke it in like the clymer manual said too even know the guy that built it said just to take it easy on it for the first 10 min before i start rippin on it.After breaking it in i took it on a paved road and went threw the gears at about 3/4 throttel and when i hit 6th it locked up.It started right back upbut now when you give it 2/4 throttel i can hear a rattleing noise,so i towed it back and did a compession test one jug is 95 psi and the other is 100 psi and the side that is 100psi the gauge starts going down.I got the guy that built it to jet it for this area to avoid a running lean,but i think thats what happened,what do you guys think?Is it my fault or the builder?Any advice on what i should do next would be nice,thanks guys. Quote Link to comment Share on other sites More sharing options...
!TWISTER! Posted April 10, 2007 Report Share Posted April 10, 2007 (edited) Open it and take pictures I would like to see the domage. You didn't said anything relate to the new modifications, it's a bit hard. Maybe something with the squish clearance or something with the ring, bad seal? Anybody ? Edited April 10, 2007 by !TWISTER! Quote Link to comment Share on other sites More sharing options...
boonman Posted April 10, 2007 Report Share Posted April 10, 2007 Some simple things you can do without actually cracking a nut or bolt on the motor for him to blame you for something would be to pull the pipes off. Gently roll the motor over, and look in the exhaust port. You should see the piston, and if it leaned out, you will see scoring on the piston, and perhaps some melted aluminum bleeding down the side of the piston in the exhaust port side of the piston. This an indication of leaning out. You can also check to make sure a ring didn't catch. You could also pull a plug to have a peek at that. You will want to look at the plug for specs of aluminum, which would be a sign of detonation. also, look for a hole in the top of the piston. One can complement the other, and make it worse. Basically, a lean condition, on a motor that is on the verge of detonation will accelerate it's progress in the detonation factor. Detonation can be caused by improper squish(you just had the motor rebuilt, was the head cut to a different piston previously to cause an improper squish?) too much advance or too much compression for the octane fuel your using. You will hear detonation as what is referred to as "pinging". You may have also wound the crank out of phase, which is unlikely, but possible if not welded. Either way, you have to locate what happened, if you expect to be able to point any fingers. And if you crack that motor open, you have no leg to stand on. But as mentioned previously, there are some things you can do to try to determine what happened. Quote Link to comment Share on other sites More sharing options...
375hp banshees Posted April 10, 2007 Report Share Posted April 10, 2007 Ok i just spent a grand getting a new top end on my shee,i broke it in like the clymer manual said too even know the guy that built it said just to take it easy on it for the first 10 min before i start rippin on it.After breaking it in i took it on a paved road and went threw the gears at about 3/4 throttel and when i hit 6th it locked up.It started right back upbut now when you give it 2/4 throttel i can hear a rattleing noise,so i towed it back and did a compession test one jug is 95 psi and the other is 100 psi and the side that is 100psi the gauge starts going down.I got the guy that built it to jet it for this area to avoid a running lean,but i think thats what happened,what do you guys think?Is it my fault or the builder?Any advice on what i should do next would be nice,thanks guys. your tester is bad ...the shrader valve stops it from going back down...you obviously have problems, but you need to fix the gauge to prevent future problems...if you broke it in properly then take it back & see what he says?...don't know if I'd let him build it again (providing it wasn't your fault?) but see what he says? Quote Link to comment Share on other sites More sharing options...
warbags Posted April 10, 2007 Author Report Share Posted April 10, 2007 My mods are fmf sst pipes k&n filter no lid on the air box,the motor is stock and this was its first time being bored so its 0.25 over stock.The plugs look the color they are suppose to be and clean no metal flakes.I guess i`ll just pull the pipes and see if i can see any thing but i don`t think it would be smart to tear it down ,i`ll let him do that and see what he says but im sure he`ll say its my fault. Quote Link to comment Share on other sites More sharing options...
Screaming Yellow Zonker Posted April 10, 2007 Report Share Posted April 10, 2007 My plugs are a dark brown color and that is how I like them. that means I am not going to lean burn it. it sounds like you lean burned your engine. find out what jets are in the carbs and let us know. Quote Link to comment Share on other sites More sharing options...
375hp banshees Posted April 10, 2007 Report Share Posted April 10, 2007 My mods are fmf sst pipes k&n filter no lid on the air box,the motor is stock and this was its first time being bored so its 0.25 over stock.The plugs look the color they are suppose to be and clean no metal flakes.I guess i`ll just pull the pipes and see if i can see any thing but i don`t think it would be smart to tear it down ,i`ll let him do that and see what he says but im sure he`ll say its my fault. the only thing that is different is bore & new pistons gaskets ect... same everything else, why did you rebuild it ? Quote Link to comment Share on other sites More sharing options...
warbags Posted April 10, 2007 Author Report Share Posted April 10, 2007 My main jets are 280 and the clip is on the second notch on the needle jet im at 1500 feet above sea level.My plugs where a nice brown not to dark not to light.I rebuilt the top end cause the psi was at 90. Quote Link to comment Share on other sites More sharing options...
MILO Posted April 10, 2007 Report Share Posted April 10, 2007 you could also pull off the carbs and reed cages and take a gander at the pistons from that side also. but i wouldn't rip into the motor without checking things out as listed above. since the builder did the jetting for you also, that may help you out if you go back to complain. if all you have done is piped and filtered, 280 may be way lean at 1500 ft. i'm at 1250 ft and with just pipes and filtered, i ran 360's to get good plug chops. Quote Link to comment Share on other sites More sharing options...
boonman Posted April 10, 2007 Report Share Posted April 10, 2007 you could also pull off the carbs and reed cages and take a gander at the pistons from that side also. but i wouldn't rip into the motor without checking things out as listed above. since the builder did the jetting for you also, that may help you out if you go back to complain. if all you have done is piped and filtered, 280 may be way lean at 1500 ft. i'm at 1250 ft and with just pipes and filtered, i ran 360's to get good plug chops. Trouble with pulling the reed cages, is that you are cracking into bolts on the motor. Looking into the exhaust port will tell you if it was leaned out. If a 2 stroke leans out, it will melt the exhaust port side of the crown of the piston. If it detonated, than there will be a hole in the top of the piston, very close to dead center under the spark plug. With pipes and a filter, open airbox, I run 300 mains, and 310-320 for colder temps. 360 mains are HUGE! I'm at 900'. Original poster needs to pull the pipes off, and look to check the exhaust side of the piston. If nothing there, than pull the carbs off, but I wouldn't go further. It may have also sucked the reeds in, if they weren't installed properly. I have never seen both go at once though. Quote Link to comment Share on other sites More sharing options...
warbags Posted April 10, 2007 Author Report Share Posted April 10, 2007 Trouble with pulling the reed cages, is that you are cracking into bolts on the motor. Looking into the exhaust port will tell you if it was leaned out. If a 2 stroke leans out, it will melt the exhaust port side of the crown of the piston. If it detonated, than there will be a hole in the top of the piston, very close to dead center under the spark plug. With pipes and a filter, open airbox, I run 300 mains, and 310-320 for colder temps. 360 mains are HUGE! I'm at 900'. Original poster needs to pull the pipes off, and look to check the exhaust side of the piston. If nothing there, than pull the carbs off, but I wouldn't go further. It may have also sucked the reeds in, if they weren't installed properly. I have never seen both go at once though. It had 290 mains and the builder put 280 mains in it,but i guess either way it was still to lean cause it was a little chilly the day it blew.My next question is would it still start and idle fine if it leaned out or sucked the reeds in.It starts and idles fine but when you give it a little gas you can hear a rattleing sound that should not be there,im starting to think it might be the crank.The builder wants me to bring it back so i guess i`ll wait and see what he says,but i asked him twice if the crank was ok before i picked it up and he said it was fine.I don`t know im just pissed you would think a $1000 for a op end would at least get you more than 30 min of riding especialy after i took every precausion to break it in right. Quote Link to comment Share on other sites More sharing options...
Wallrat Posted April 10, 2007 Report Share Posted April 10, 2007 $1000 for a top end? Holy crap that's insane! Do your own work, it'll cost you about 1/4 that much to do it yourself. Quote Link to comment Share on other sites More sharing options...
warbags Posted April 10, 2007 Author Report Share Posted April 10, 2007 $1000 for a top end? Holy crap that's insane! Do your own work, it'll cost you about 1/4 that much to do it yourself. Oh ya thats canadian dollars ,but ya if he does`nt wanna fix it i think i`ll give it i try. Quote Link to comment Share on other sites More sharing options...
syclone Posted April 11, 2007 Report Share Posted April 11, 2007 i bet your piston skirt to cylinder wall clearance was to tight Quote Link to comment Share on other sites More sharing options...
warbags Posted April 11, 2007 Author Report Share Posted April 11, 2007 Well i just got back from my builders shop,and man i feel like such an idiot,i just put a dg skid plate on and i did`nt lock tite the mounting scerws so there where a couple mounting brackets loose so thats what the rattleing noise was.He checked the compression and it was 135/135.but he could`nt explain why it locked up and died.thanks for all the help guys Quote Link to comment Share on other sites More sharing options...
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