bada Posted June 3, 2007 Report Share Posted June 3, 2007 Ok I just had motor rebuilt from ground up.I guess I am not made for a 2 stroke everytime I ride it something goes wrong.What am i doing wrong?I dont hold it wide open or for a long time.Whats the purpose of having a bike you cant race 2 or 3 races in a row?Ok its a 4mil stroker short rod,40 over cylinders mild port with boost ports,matched cases,+7 timming,v3s,with K&ns open,35pjs on alky,wicked straight drag out frame,1-4 overide cool head 18cc domes cut,I just recently started ridind maybe about 3 times. So i bring it to the sand to see if it shift through and runs wright.It sounds like what yall call detonation at high rpms.It started running bad so i shut it down and white burnt smelling smoke came out of exaust after killing it.Got home and fired her back up it took alot of kicks but it started.Now engine ice is comming out of one of my pipes.Did a comp test and it is still near 180 in each.But it fell.Iguess this is symptons of head gasket.(coolhead)The thing is i dont even have maybe 1 hour on rebuild with new seals to orings ect..How can I stop detonation?And does anyone have a clue on what jets i should run with this setup?Also my headpipe has a little slack in cyliders not a very good seal but doesnt shoot fluids out can this harm my engine? Please help me I am at the point were i am ready to go back four stroke.I rode it 5 time before i blew it up last time.And now its 3 times and she is near dead already after 3000 bucks. What am I doing wrong please help..... Quote Link to comment Share on other sites More sharing options...
dynodon Posted June 3, 2007 Report Share Posted June 3, 2007 (edited) I wouldnt run anything like "engine ice" if your on alky. The motor needs some heat in it. I run straight water in mine that is on alky. The water leaking SOUNDS like an O-ring may not have been seated correctly at assembly( they can be a bitch to get right, there are a few tricks to use also) As for the smoke, that could have just been the "engine ice" burning off, BUT with out seeing the bike in person its hard to say. Further more, If your running alky, forget everything you know about tuning a gas engine ( as far as the correct visual on plug) alky is the opposite of gas. Now for the jetting and such, You should get in touch with the builder ( who ever you bought the parts from) and see what they say you should be jetted at for your set up, and elevation. You can see if you have any signs of deto by taking the pipes off and look in the cylinders with a flash light. ( with the piston all the way down) or stick your finger in and feel the top of piston I know this probably doesnt seem to help you much, BUT it will in the long run. GOOD LUCK Edited June 3, 2007 by dynodon Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted June 3, 2007 Report Share Posted June 3, 2007 White smoke means your butning coolant. Why do you have a drag bike with a mild port job on alcohol? Quote Link to comment Share on other sites More sharing options...
blowit Posted June 3, 2007 Report Share Posted June 3, 2007 Yeah, sounds like you had some detonation and that will cause a drastic rise in temps and pressures. Very common to smoke an oring with detonation. Pull the head and take a peek. You should see obvious damage if it has been detonating. Brandon Quote Link to comment Share on other sites More sharing options...
bada Posted June 3, 2007 Author Report Share Posted June 3, 2007 First of all the cylinders were sent off to duncan and a national port job was done.My builder went over it with what he calls a drag port.Second what kind of damage will detonation show on the pistons,and will i have to rebuild from detonation?I have less than a hour on motor.Thanks for response Quote Link to comment Share on other sites More sharing options...
dajogejr Posted June 3, 2007 Report Share Posted June 3, 2007 Having issues with my 10 mil too. Did you bother to check the squish when you put the motor back together, possible that's too tight. 180 is a good PSI to run on alky...if your squish is ok. Leaking coolant will cause it to lean out real fast. I burned up a ground strap first time out this year. I personally think it's my cool head, warped... I'm gonna have it checked out to make sure the ORing grooves are good, and it's completely flat. My Noss head ran like a top on my 4 mil last year on gas...all day long. I've had nothing but coolant leaking problems this year... Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted June 3, 2007 Report Share Posted June 3, 2007 Detonation looks like this. Banshee hq link Quote Link to comment Share on other sites More sharing options...
bada Posted June 5, 2007 Author Report Share Posted June 5, 2007 Ok i took my pipes off and looked at pistons and what I could see of my cylinders.When i pulled my pipe off one had ALOT of coolant in it pored it out it was so much.The tops of the pistons didnt look bad or abnormal nor did the sides the pistons or rings or cylinderwalls,but while i was barley kicking it over too look at the pistons you coul see the coolant leak,will this harm the inside of the motor?because the pipe had alot in it..Is this normal for a cool head gasket going out? Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted June 5, 2007 Report Share Posted June 5, 2007 It should be ok as long as the motor did not stop from not being able to compress the water. If that happens, then you can bend a rod. Quote Link to comment Share on other sites More sharing options...
bada Posted June 5, 2007 Author Report Share Posted June 5, 2007 Anyone else? Quote Link to comment Share on other sites More sharing options...
blowit Posted June 7, 2007 Report Share Posted June 7, 2007 Anyone else? Yes, it is common to smoke orings. Sometimes for no reason and sometimes from detonation. I would not be as concerned about hydro locking the motor as much as why the head is leaking so bad and for how long it ran like this. You pistons are clean because they just got power washed. Introducing water to an engine is not always a bad thing in moderation. Things end up clean as a whistle. Consider you problem as damage already done or no harm done. Either way, put it together and ride it. If it happens again, they you have a problem. If you forgot your locating dowel on the base of the cylinders, that can cause a flatness issue for the head to mate too. Just buy and try. But keep your ear tuned for detonation. Blown head gaskets are a very good indicator of that. Brandon Quote Link to comment Share on other sites More sharing options...
shanYE west Posted June 7, 2007 Report Share Posted June 7, 2007 (edited) Wouldn't running the bowls dry cause deto? If he's not running a pump or oversize bowls I dont think it would take a very long pass to run the bowls dry. Also, I dont think you can use standard size mains jets. I think they have to be drilled out to size. I know my mains and tubes were drilled but I'm not sure about the smaller carbs. If your running standard size main jets maybe that lean main jet could be causing deto.? I'm by no means a expert on alky, I'm learning about it myself. Someone can chime in if I'm wrong. Edited June 7, 2007 by Fouledout420 Quote Link to comment Share on other sites More sharing options...
blowit Posted June 7, 2007 Report Share Posted June 7, 2007 Wouldn't running the bowls dry cause deto? If he's not running a pump or oversize bowls I dont think it would take a very long pass to run the bowls dry. Also, I dont think you can use standard size mains jets. I think they have to be drilled out to size. I know my mains and tubes were drilled but I'm not sure about the smaller carbs. If your running standard size main jets maybe that lean main jet could be causing deto.? I'm by no means a expert on alky, I'm learning about it myself. Someone can chime in if I'm wrong. No, I agree with you. Possibly a lean motor. Sounds like detonation at this point. I would like to inspect the head, plug, and oring to determine that. Brandon Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted June 7, 2007 Report Share Posted June 7, 2007 Replace the bad 0-ring, inspect your pistons, put it back together. Sounds to me like this was most likely your initial problem. Some things can dislodge an o-ring like detonation but usually rings, plugs, or a piston will go 1st. To be safe you may richen your jetting a tad then do a plug check. Quote Link to comment Share on other sites More sharing options...
bada Posted June 7, 2007 Author Report Share Posted June 7, 2007 Come to find out my domes were cracking where they were cut for my 4 mill.They had hairline cracks all the way around them and some had chips that was broken off thats were the coolant was getting in..Were can i buy some cheap domes?And whats the average price on getting them cut? Quote Link to comment Share on other sites More sharing options...
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