aztwin350 Posted July 3, 2013 Author Report Share Posted July 3, 2013 false.....you can have a leak at your reeds, or base gaskets and it wont show on a compression test. All the compression test is going to do is indicate whether both cylinders are healthy in relation to each other and to HELP aid in choosing an octane rating for fuel. NOW....a leakdown test is totally different in terms of a healthy bike. As 2strokes need fuel mixed with oil to lubricate......air causes extra internal temps which do all sorts of odd things to motors from melting pistons, to punching a connecting rod out the bottom. You cant tell by riding it if it has an air leak and is being compensated for with huge jets. I mean shit......I run a dune/play port, vf2 reeds, k&n pods, 20cc domes, and fmf fatties, and I am running fresh 93 and am running 330 main jets at 80* and 1100' ok on my next day off i will check the compression and do a plug chop. the guy i bought it from said he would mix race gas with 91. i was going to but no one in town carries any. the best i can do is 91 with some octane boost. he said i didnt have to use race gas but could if i wanted. so if it has higher compression i have to use better gas. Quote Link to comment Share on other sites More sharing options...
aztwin350 Posted July 3, 2013 Author Report Share Posted July 3, 2013 For one thing dump the boost bottle, it does nothing but crack carb boots, where you may be leaking air. Either get a stock crossover tube or get some pvc caps to fit the holes. That's what I did, installed with Yamabond and clamps. Not knowing what your domes are could be the problem. If you wanted to play it safe put a stock head on until you sort it out. Make sure there are no pits in it and that it's flat and clean. Search the forum on how to build a leak tester. so if it has a bottle it isnt stock. i dont see any name brand or anything on it. also i have lever chokes instead of pull chokes like i see on a lot of banshees. is there numbers on them to see if what size they are or stock. i was trying to load a pic of the bottle but cant get it to load. Quote Link to comment Share on other sites More sharing options...
Starwriter Posted July 3, 2013 Report Share Posted July 3, 2013 Were you dropped on your head as a child? You have a boost bottle, too big of mains for it to even run, and you can't seem to get it through your thick skull that you probably have cracked intake boots. When it seizes at the end of your plug chop run, be sure to post pics of the carnage. We like carnage pics. Quote Link to comment Share on other sites More sharing options...
aztwin350 Posted July 3, 2013 Author Report Share Posted July 3, 2013 your lame first of all. second my quad runs, just not perfect. if you have nothing helpful shut your mouth and move on. im trying to get help with a problem. sorry you never nedded help with anything. larry shee was the first one that said anything about intake boots. im open to suggestions from smart and knowledgeble peope nbut not you. if your not here to help people out dont respond Quote Link to comment Share on other sites More sharing options...
Starwriter Posted July 3, 2013 Report Share Posted July 3, 2013 (edited) Listen dumb ass, we told you not to run it till you do a leakdown test. If you choose to ignore that and run it WFO in 6th to do a plug chop and blow it up, don't cry the blues around here. This thread is just about word for word like the Kozyshack thread except he rebuilt the top end and then blew it up. Edited July 3, 2013 by Starwriter Quote Link to comment Share on other sites More sharing options...
hoppedupandcutdown Posted July 3, 2013 Report Share Posted July 3, 2013 WOW noob, Starwriter is one of the most helpful and knowledgeable members here, what you fail to understand is at your temp and elevation and jet you say you're running --- something is terribly wrong ! Quote Link to comment Share on other sites More sharing options...
aztwin350 Posted July 3, 2013 Author Report Share Posted July 3, 2013 Listen dumb ass, we told you not to run it till you do a leakdown test. If you choose to ignore that and run it WFO in 6th to do a plug chop and blow it up, don't cry the blues around here. This thread is just about word for word like the Kozyshack thread except he rebuilt the top end and then blew it up. i havent ran it since people said to do a leakdown test i never said i did. and what was kozyshack problem. like i said im not 100 % sure on a leakdown test. ive looked up videos but the only one i saw are for single cylinders. are twin cyliinders different i dont know. thats why im asking for help. your response was not helpful. i havent done a plug chop yet. i was waiting for a day off. ive ridden the quad for long periods o ftime im not saying it was good for it but if it was that far off it would have blown by now i feel. im not trying to blow it up riding it. ive done many 6 gear runs trying different needle positions and a couple different jets. i dont think a plug chop would blow it up but who knows. is there any way to check for leaks besides a leakdown test Quote Link to comment Share on other sites More sharing options...
Chris327 Posted July 3, 2013 Report Share Posted July 3, 2013 Listen dumb ass, we told you not to run it till you do a leakdown test. If you choose to ignore that and run it WFO in 6th to do a plug chop and blow it up, don't cry the blues around here. This thread is just about word for word like the Kozyshack thread except he rebuilt the top end and then blew it up. ooooooooooooohhhhh....fuck that kid got shitted on.... Starwriter layin down the law! Quote Link to comment Share on other sites More sharing options...
aztwin350 Posted July 3, 2013 Author Report Share Posted July 3, 2013 WOW noob, Starwriter is one of the most helpful and knowledgeable members here, what you fail to understand is at your temp and elevation and jet you say you're running --- something is terribly wrong ! justwannarace on another post said 300-320 main nedle in middle and 1.5 turns out. other people said that is close for my elevation and mods so im not that far off. all i was asking originally is what is a good compression with what known mods are on the quad. Quote Link to comment Share on other sites More sharing options...
aztwin350 Posted July 3, 2013 Author Report Share Posted July 3, 2013 ooooooooooooohhhhh....fuck that kid got shitted on.... Starwriter layin down the law! i cant stand dumb motherfuckers like you. i love it when people act tuff on the keyboard. isnt it past your bedtime little boy. go watch dora in your car bed Quote Link to comment Share on other sites More sharing options...
Jereme6655 Posted July 3, 2013 Report Share Posted July 3, 2013 aztwin........yes there are a lot of knowledgeable guys on here, yes we do help, but yes we do get irritated when people ignore the correct ways to ensure they're bike runs good and jump steps. We've all seen it before and then theres a guy with a chip on his should who wont shut up about how we helped blow up his motor. So yes, we have a tendency to get rough sometimes with some people tht seem like they may jump steps. To do a leak down test you need to get caps or plugs that will plug both exhaust ports shut air tight. There is a thread on here (I believe in the technical page) that shows exactly how to build the tester. When it comes time to do the test......you want to pressurize your motor to ONLY 6psi. Then watch the pressure.......if it drops you have a leak. What you are WANTING to see is 6psi holding for 6minutes. What is acceptable is to start at 6psi and to lose not more than 1psi per minute of the test. If you start to lose pressure grab a spray bottle with some dish soap and water in it and start spraying.......you WILL find the leak with the bubbles. This test is to ensure you have an air tight motor and will help you diagnose problems. You don't want to be running massive sized jets to "overcome" an air leak........that's asking for a bigger problem. We like to build things right and have them last...... Quote Link to comment Share on other sites More sharing options...
Larry's Shee Posted July 3, 2013 Report Share Posted July 3, 2013 My son's setup: unported 4mil, FMF signatures, Vitos reeds, stock head with 2mil head spacer. 300m 27.5p mid clip, 70*, 1000ft elev. 330m on the ice,near 0*. A boost bottle could be put on a bone stock bike and it would still be considered stock. If you have lever type chokes they are not stock carbs. When you have them off measure inside bore at the engine side. I don't recall which site sponser it was but they had a chart that told how much smaller domes would have to be to keep the same compression from sea level on up. Octain booster is bullshit, adding that IS NOT the same as mixing race gas 50/50 Sorry, but I don't see in this thread where anyone has said your jetting is good. There is a sticky where lots have posted their set-ups and jetting, might want to look through that. Granted that 90% are for under 2000' elev so you would have to compensate there. You can lead a horse to water, but you can't make him drink. Quote Link to comment Share on other sites More sharing options...
aztwin350 Posted July 3, 2013 Author Report Share Posted July 3, 2013 My son's setup: unported 4mil, FMF signatures, Vitos reeds, stock head with 2mil head spacer. 300m 27.5p mid clip, 70*, 1000ft elev. 330m on the ice,near 0*. A boost bottle could be put on a bone stock bike and it would still be considered stock. If you have lever type chokes they are not stock carbs. When you have them off measure inside bore at the engine side. I don't recall which site sponser it was but they had a chart that told how much smaller domes would have to be to keep the same compression from sea level on up. Octain booster is bullshit, adding that IS NOT the same as mixing race gas 50/50 Sorry, but I don't see in this thread where anyone has said your jetting is good. There is a sticky where lots have posted their set-ups and jetting, might want to look through that. Granted that 90% are for under 2000' elev so you would have to compensate there. You can lead a horse to water, but you can't make him drin so you do not need the crosover tube or bottle at all. how will this affect the bike if at all. i know that the booster is crap the local shop said to at least try that to see if it would help. closest place with good gas is about a hour away. looks like i should make the trip.it was in a different thread i had about the head i have. i was unsure when i got it. by that information i thought i was somewhat close. i hope i am. ill check the carbs and see the size. what size are stock . and im still wondering what a good compression number would be. Quote Link to comment Share on other sites More sharing options...
aztwin350 Posted July 3, 2013 Author Report Share Posted July 3, 2013 aztwin........yes there are a lot of knowledgeable guys on here, yes we do help, but yes we do get irritated when people ignore the correct ways to ensure they're bike runs good and jump steps. We've all seen it before and then theres a guy with a chip on his should who wont shut up about how we helped blow up his motor. So yes, we have a tendency to get rough sometimes with some people tht seem like they may jump steps. To do a leak down test you need to get caps or plugs that will plug both exhaust ports shut air tight. There is a thread on here (I believe in the technical page) that shows exactly how to build the tester. When it comes time to do the test......you want to pressurize your motor to ONLY 6psi. Then watch the pressure.......if it drops you have a leak. What you are WANTING to see is 6psi holding for 6minutes. What is acceptable is to start at 6psi and to lose not more than 1psi per minute of the test. If you start to lose pressure grab a spray bottle with some dish soap and water in it and start spraying.......you WILL find the leak with the bubbles. This test is to ensure you have an air tight motor and will help you diagnose problems. You don't want to be running massive sized jets to "overcome" an air leak........that's asking for a bigger problem. We like to build things right and have them last...... i would never blame people for blowing something up. you guys arent riding it but i understand what your saying. ill definately try to get a leakdown done on it and get some compression numbers as well. Quote Link to comment Share on other sites More sharing options...
trickedcarbine Posted July 3, 2013 Report Share Posted July 3, 2013 Good compression? Between 100-220 kicking psi. You need to determine whether you have an air leak or detonation or combo of both...., Quote Link to comment Share on other sites More sharing options...
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