toffeecrisp Posted July 27, 2010 Share Posted July 27, 2010 hi all i brought this bike and this is the problem the person who had it the thread got knackered on the head then it decided to crack, replaced it with a standard 125 head and piston, now when i try to start it, it will try and try then backfire with a little white smoke and try some more but wont start.aparently it was working fine before even though the head was the spark is sparking petrol flowing and 2 stroke lubricating, i cant see why it wont start as all thats been don is had is had replace the broken head and pistons so its a tzr 1995 model and i need this for work the peron said to me it's the main jet which is a 260 and needs to be a 210 it beem bored to 65.5mm i now have standard head which is 56mm bore and piston please help many thanks. Link to comment Share on other sites More sharing options...
Paulwhite Posted July 27, 2010 Share Posted July 27, 2010 did you just put a new standard piston in? if so then thats why it wont work! you will need a slightly bigger piston/rings so that you can get compression. the standard head should be ok but you will probably find that you will go through head gaskets like toilet paper. best thing to do is contact the previous owner and find out where he got the work done then ask them. Link to comment Share on other sites More sharing options...
toffeecrisp Posted July 27, 2010 Author Share Posted July 27, 2010 did you just put a new standard piston in? if so then thats why it wont work! you will need a slightly bigger piston/rings so that you can get compression. the standard head should be ok but you will probably find that you will go through head gaskets like toilet paper. best thing to do is contact the previous owner and find out where he got the work done then ask them. how long will the head gasket last roughly?? Link to comment Share on other sites More sharing options...
Paulwhite Posted July 27, 2010 Share Posted July 27, 2010 if only there was an answer to that question. it could last 2 days or 2 years no one can tell due to it all depends on a number of factors like how old the bike is, how aggressive you ride, how much force is created at the point of ignition. ect. ect. as iv said m8 find out who carried out the work and get their opinion. with the boar being bigger, the piston needs to be bigger , but the boar of the head is smaller so you need to either get a better head (or get it machined to match) or see about a special gasket setup that allows you to use the original head. normally its just an extra thick gasket or a metal one that slightly increases the gap between piston and head to allow you to use original heads with board out barrels. Link to comment Share on other sites More sharing options...
toffeecrisp Posted July 27, 2010 Author Share Posted July 27, 2010 if only there was an answer to that question. it could last 2 days or 2 years no one can tell due to it all depends on a number of factors like how old the bike is, how aggressive you ride, how much force is created at the point of ignition. ect. ect. as iv said m8 find out who carried out the work and get their opinion. with the boar being bigger, the piston needs to be bigger , but the boar of the head is smaller so you need to either get a better head (or get it machined to match) or see about a special gasket setup that allows you to use the original head. normally its just an extra thick gasket or a metal one that slightly increases the gap between piston and head to allow you to use original heads with board out barrels. thank you so much for your help Link to comment Share on other sites More sharing options...
Recommended Posts