400banshee Posted February 19, 2011 Report Share Posted February 19, 2011 http://i520.photobucket.com/albums/w323/bansheet3502008/100_4669.jpg hey i have a 485 cheetah pv and on the first ride today and this shit happened the insulator broke and smoked my motor never had this heppen so befor i fix it i want to have a idea of the real cause of this dont want it to do this again Quote Link to comment Share on other sites More sharing options...
WINDYCITYJOHN400 Posted February 19, 2011 Report Share Posted February 19, 2011 Need more info. Was this the first ride ever on this motor, or just the first ride this season? Who built the motor ? Carb sizes, jetting, fuel, compression, timing? Quote Link to comment Share on other sites More sharing options...
400banshee Posted February 19, 2011 Author Report Share Posted February 19, 2011 (edited) ever on this motor 35 mm carbs with 145 main and 44 pilot timing is +4 comp is 150 psi .049 squish Edited February 19, 2011 by 400banshee Quote Link to comment Share on other sites More sharing options...
THE358BANSH Posted February 19, 2011 Report Share Posted February 19, 2011 Did you drop the plug while handling of putting it in? If a plug hits the ground, I don't even think about using it. Just get another and slap it in. Cheap insurance... Quote Link to comment Share on other sites More sharing options...
jbooker82 Posted February 19, 2011 Report Share Posted February 19, 2011 Detonation from improperly cut Trinity Domes? Who or where did you get the cylinder head domes from? Quote Link to comment Share on other sites More sharing options...
400banshee Posted February 19, 2011 Author Report Share Posted February 19, 2011 trinity my buddy has the same one no prob but another guy had the same thing happen Quote Link to comment Share on other sites More sharing options...
Larry's Shee Posted February 19, 2011 Report Share Posted February 19, 2011 http://bansheehq.com/forums/index.php?showtopic=131445 Quote Link to comment Share on other sites More sharing options...
WINDYCITYJOHN400 Posted February 19, 2011 Report Share Posted February 19, 2011 (edited) Well most people who follow my rants will be surprised I didn't start with throwing Trinity under the bus. I thought for once I'd wait till you said trinity sold it before I just went off. Trinity is making a real habit of shipping domes that don't work well on these 4 mil cheetahs. They blow O-rings like it's going out of style, or suffer some other form of lethal detonation. Check that squish. Mine was alot tighter than yours.... I had .030 on one side and .029 on the other and 200 psi !!! But the bigger deal was that the SHAPE was tighter at the piston crown than at the sides. this was putting all the force at the piston edges,rings and O-rings. I'm usually the one who does the hard core rant and vents about this crap, but just for kicks I'd like to have you first look in the Product Reviews section in a post titled "Trinity Blows". ( "Larry's Shee" was kind enough to put a link in the above post.) Read all the pages first to last. Then PM "nickisgod" and "mailman" and see what they say. Once you do that reading/research, come on back and give us your thoughts on the things you've heard. I'd like to hear the thoughts of someone who's eye's have been opened to the sickening reality of the Trinity experience. I'm getting tired of prying peoples eyes open and forcing them to realize they got screwed. ( I hate being the messenger....people always want to kill the messenger. I'd like to be the one who helps you fix the problem...not the guy who told you that you had one. LOL) For what is worth...your plug didn't destroy your motor.......your motor destroyed your plug! Then it commited suicide with the plug pieces. P.S. - Your problem is....your bike has V.D. !!! Once you figure out what that means, you'll be headed out of the darkness and into the light. ( Note: The answer is in the research ) Edited February 19, 2011 by WINDYCITYJOHN400 Quote Link to comment Share on other sites More sharing options...
dirtydownunder Posted February 19, 2011 Report Share Posted February 19, 2011 i have to say a faulty plug, ive seen some crazy shit happen inside combustion chambers, but never a clean chunk removed from the insulator. Quote Link to comment Share on other sites More sharing options...
pabansheematt Posted February 19, 2011 Report Share Posted February 19, 2011 Call me crazy, but I dont think its the domes. I have the same motor, but mine has 73.5 bore. I never had any problems. I think it was a jetting issue. But I guess we'll see today when Brian gets it apart. Quote Link to comment Share on other sites More sharing options...
400banshee Posted February 19, 2011 Author Report Share Posted February 19, 2011 Quote Link to comment Share on other sites More sharing options...
camatv Posted February 19, 2011 Report Share Posted February 19, 2011 hmm well here's a start its got the wrong o-rings in it it was lifting the head enough to blow the o-rings out. causing them to look like that, was also mostlikely eating coolant also. the heads i have found need to just about fall on the cylinder if you have to beat them on or push REALLY hard they wont tq right and are prone to blowing o-rings. also they seem to like a very flat profile and a very small squish band like around 9mm!! or even less. get VITON o-rings. get lesser squish domes ( like .49-55) and you may want to just drill out the head just a smidgin i mean just enough on the stud holes that the head goes right on and right off. the higher sqush band will make the motor rev MUCH easier and actually make more tq. and be even more potnet overall. and also make sure the squish angle is correct for the domes.. they are getting a LIL better i rember when there was almost NO dome in there adn it was ALL squish band like 15-20mm!!!! those were some detoin, o-ring eating fools if you want check out RKtech heads they have a SWEET head/dome set up for these motors.. and witha lil bit of measuerment can make a sweet custom domes set for your motor its well worth the $$$$ Quote Link to comment Share on other sites More sharing options...
pabansheematt Posted February 20, 2011 Report Share Posted February 20, 2011 hmm well here's a start its got the wrong o-rings in it it was lifting the head enough to blow the o-rings out. causing them to look like that, was also mostlikely eating coolant also. the heads i have found need to just about fall on the cylinder if you have to beat them on or push REALLY hard they wont tq right and are prone to blowing o-rings. also they seem to like a very flat profile and a very small squish band like around 9mm!! or even less. get VITON o-rings. get lesser squish domes ( like .49-55) and you may want to just drill out the head just a smidgin i mean just enough on the stud holes that the head goes right on and right off. the higher sqush band will make the motor rev MUCH easier and actually make more tq. and be even more potnet overall. and also make sure the squish angle is correct for the domes.. they are getting a LIL better i rember when there was almost NO dome in there adn it was ALL squish band like 15-20mm!!!! those were some detoin, o-ring eating fools if you want check out RKtech heads they have a SWEET head/dome set up for these motors.. and witha lil bit of measuerment can make a sweet custom domes set for your motor its well worth the $$ Personaly, I think what you say makes perfect sence. I have nearly, the same motor. I had to file my domes to get them to fit. I only rode it 2 times. but it ran great. Quote Link to comment Share on other sites More sharing options...
400banshee Posted February 20, 2011 Author Report Share Posted February 20, 2011 hmm well here's a start its got the wrong o-rings in it it was lifting the head enough to blow the o-rings out. causing them to look like that, was also mostlikely eating coolant also. the heads i have found need to just about fall on the cylinder if you have to beat them on or push REALLY hard they wont tq right and are prone to blowing o-rings. also they seem to like a very flat profile and a very small squish band like around 9mm!! or even less. get VITON o-rings. get lesser squish domes ( like .49-55) and you may want to just drill out the head just a smidgin i mean just enough on the stud holes that the head goes right on and right off. the higher sqush band will make the motor rev MUCH easier and actually make more tq. and be even more potnet overall. and also make sure the squish angle is correct for the domes.. they are getting a LIL better i rember when there was almost NO dome in there adn it was ALL squish band like 15-20mm!!!! those were some detoin, o-ring eating fools if you want check out RKtech heads they have a SWEET head/dome set up for these motors.. and witha lil bit of measuerment can make a sweet custom domes set for your motor its well worth the $$$$ thank you for a great answer it is very helpfull i beleave that what you said is what happened as for the drilling the head you me the domes in this case i had to force them on thank you brian ps any info you can give me would be great Quote Link to comment Share on other sites More sharing options...
gotta_goatsfast Posted February 20, 2011 Report Share Posted February 20, 2011 ever on this motor 35 mm carbs with 145 main and 44 pilot timing is +4 comp is 150 psi .049 squish Never running a 485, my opinion might be void but 145 main and 44 pilot jets on that large of a motor sounds incredibly lean. Most 421cc cubs are running 160+ mains and 50+ pilots. What is your elevation? It could be possible that detonation/heat cracked your insulation? Anyway, carry on... Quote Link to comment Share on other sites More sharing options...
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