I hope its just the Top end!!!!!

Lol....

91oct. @32:1........ But I'm 180 pounds and I was trying to keep up to a 1985 250r
on some big bowls.it was red line most of the time.... I bought it for my son...need to get it fixed....



what was your static compression what premix oil and i bet you ran cheap pump gas at sea level didnt you
 
backwards?

How do you spin it backward?



ya and if u dont have alot of money in the engine u can spin it backwards and it should free up to clean it out. usually there are melted peices in the rod bearing where it meets the crank and it hits the case and wont let it turn over. i always split the case and replace main crannk bearings. but to each his own. sucks to know u have melted piston in ur main bearings, would make me scred to get on it knowing bottom end isnt 100%.
and i would like to add one thing to what daniel said. dont forget to hone the cylinder.
SDBLASTER. FUNNY old school vids i thought it was a jacked up video untill i realized u was shooting it with a VHS!!! hahaahha
 
?

Ok,there are two parts to the top end..the top piece with the spark plug and the other with the piston,what needs to be done to the top piece with the spark plug after getting a new piston...


I was at glamis this weekend,just got the 01 blaster,piped,jetted,reeds,so I was told.it was running good and I was running it pretty hard came over a dune and it just shut off.Kick starter has no compression. Any idea's?

I hope its just the Top end!!!!!
 
if the head isnt pitted up with aluminum you wont have to do anything(check make sure its not warped)other then clean it up.If the head is pitted up youll need to recut the head(perfect time to re design the combustion chamber)
 
the part with the piston is your cylinder..the part with the plug is your head..when you get th ehead off youll see a little circle around where the plug comes out..thats your combustion chamber..like cwhutzell said, if you see a bunch of pits in it then you should have it rechambered. which isnt expensive, i hade mine milled and chambered for $30..if its just black..dont worry, thats just carbon..soak it in gunk off and use a scotch brite pad on it, or wire brush and clean it off.. unless you have cylinder work done(bore) or a port job i wouldnt worry bout "designing " a chamber..its actualy called the squish band angle btw ....imho
 
cool

I took it all off and the rings are still attached and the cylinder looks good,I'm trying to get the piston off I took the two rings off and tried a small socked to get the cone out that sucker will not come out. and I don't want to bang on it to hard.also I vacumed it out.its seems smooth side to side until the piston goes all the why down,then it seems to get hung up.should it flow in a complete circle.How do I find out what size piston to get?


the part with the piston is your cylinder..the part with the plug is your head..when you get th ehead off youll see a little circle around where the plug comes out..thats your combustion chamber..like cwhutzell said, if you see a bunch of pits in it then you should have it rechambered. which isnt expensive, i hade mine milled and chambered for $30..if its just black..dont worry, thats just carbon..soak it in gunk off and use a scotch brite pad on it, or wire brush and clean it off.. unless you have cylinder work done(bore) or a port job i wouldnt worry bout "designing " a chamber..its actualy called the squish band angle btw ....imho
 
I took it all off and the rings are still attached and the cylinder looks good,I'm trying to get the piston off I took the two rings off and tried a small socked to get the cone out that sucker will not come out. and I don't want to bang on it to hard.also I vacumed it out.its seems smooth side to side until the piston goes all the why down,then it seems to get hung up.should it flow in a complete circle.How do I find out what size piston to get?

as long as it hasnt been bored its a standard(std) piston...yes. it should go in a complete circle. if it doesnt you have pieces of metel in there..and just to give a little more advice on this , and dont take this the wrong way, but if you dont have enough experience to know how ta remove a piston, you really should get someone to help you with this. cause you are gonna need to split the case,it sounds like you have metel fragments in there. you are lucky that the cylinder wall isnt scored up though.. this is gonna be a simple rebuild job for someone that knows whatr there doing.cause all your doing is replacing the piston. and cleaning out the base.but if you dont know what your doing you may cause more damage than good. like i said though, dont take it the wrong way, not trying to insult you. if you are gonna get brave with this and take the time to learn then ask allot of questions like your doing an dalso look in some shop manuals and study how all the parts in the case go together and work.
 
Naw...It's cool......


as long as it hasnt been bored its a standard(std) piston...yes. it should go in a complete circle. if it doesnt you have pieces of metel in there..and just to give a little more advice on this , and dont take this the wrong way, but if you dont have enough experience to know how ta remove a piston, you really should get someone to help you with this. cause you are gonna need to split the case,it sounds like you have metel fragments in there. you are lucky that the cylinder wall isnt scored up though.. this is gonna be a simple rebuild job for someone that knows whatr there doing.cause all your doing is replacing the piston. and cleaning out the base.but if you dont know what your doing you may cause more damage than good. like i said though, dont take it the wrong way, not trying to insult you. if you are gonna get brave with this and take the time to learn then ask allot of questions like your doing an dalso look in some shop manuals and study how all the parts in the case go together and work.
 
I found the video






as long as it hasnt been bored its a standard(std) piston...yes. it should go in a complete circle. if it doesnt you have pieces of metel in there..and just to give a little more advice on this , and dont take this the wrong way, but if you dont have enough experience to know how ta remove a piston, you really should get someone to help you with this. cause you are gonna need to split the case,it sounds like you have metel fragments in there. you are lucky that the cylinder wall isnt scored up though.. this is gonna be a simple rebuild job for someone that knows whatr there doing.cause all your doing is replacing the piston. and cleaning out the base.but if you dont know what your doing you may cause more damage than good. like i said though, dont take it the wrong way, not trying to insult you. if you are gonna get brave with this and take the time to learn then ask allot of questions like your doing an dalso look in some shop manuals and study how all the parts in the case go together and work.
 
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i just dont wanna se ya go banging on the piston and crank or split the case and have pieces all over your bench and not know how to get it back togather...when i split a case that i havent taken apart before i make a detailed drawing and label all my bolts, screws , parts and use zip lock bags to keep everything organized..unless im doing a motor that im familiar with, like my yz i can take apart and put back together in a few hours..also..google can be your best friend..you can ask google anything ...haha

yes, youtube has some good rebuild vids on there. i had to watch em the first time i rebuilt a rotax skidoo motor..rotery valves and all sorts of cool stuff is on them.
 
the part with the piston is your cylinder..the part with the plug is your head..when you get th ehead off youll see a little circle around where the plug comes out..thats your combustion chamber..like cwhutzell said, if you see a bunch of pits in it then you should have it rechambered. which isnt expensive, i hade mine milled and chambered for $30..if its just black..dont worry, thats just carbon..soak it in gunk off and use a scotch brite pad on it, or wire brush and clean it off.. unless you have cylinder work done(bore) or a port job i wouldnt worry bout "designing " a chamber..its actualy called the squish band angle btw ....imho


if your "re chambering"the cylinder head then your basiclly redesigning it.The design of the combustion chamber is very critical to the engines performance.Who did your head for 30 bucks????ill have to out source my head work to them,lol.to redesign a cylinder head i charge 100$,30$ is pritty cheap you sure they just didnt just machine the surface?
 
sounds a little expensive man..atleast in m yarea it would be.I have my work done by Bristol Racing of cny..another machine shop i have used on my sled motors is a company called Majestic Mold and Tool (in phoenix new york). those are the number one engine builders in my area(syracuse area) a single cylinder head will range from 30 to 60.
I had mine milled .035 and rechambered. and have had em do work to many other of my machines as well.
and like you said ..its is very criticle to the performance of the motor..thats why i told that kid not to do that unless he has some engine mods done.
I had bristol port my last motor aND the port job was big bucks, head job was cheaper...my next motor im gonna give flotek a try..still gonna stick with my own head builders thoigh..the guys are good
a blaster head isnt nothing to these guys...i remember when i brought it out to em, they took a look at it and said "well aint that a cute lil thing"..lol.. we all laughed over that one!
 
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cool

I got the motor out,I'm going to try to rinse the bottom end to see if I could get it smooth.what should I use to do that?I'm not sure if its the stock bore or not I bought it used and it has a pro circuit pipe on it with v3 reeds.i might be able to take it somewhere were they could let me know what size piston I need..thanks again



i just dont wanna se ya go banging on the piston and crank or split the case and have pieces all over your bench and not know how to get it back togather...when i split a case that i havent taken apart before i make a detailed drawing and label all my bolts, screws , parts and use zip lock bags to keep everything organized..unless im doing a motor that im familiar with, like my yz i can take apart and put back together in a few hours..also..google can be your best friend..you can ask google anything ...haha

yes, youtube has some good rebuild vids on there. i had to watch em the first time i rebuilt a rotax skidoo motor..rotery valves and all sorts of cool stuff is on them.
 
Of course the best way is the hardest way. The only sure way to get it all out is to split the cases. But if thats not in the cards do this.

Go to Wal-Mart and get a gallon of mineral spirits. Should cost you less than $5. Fill up the crankcase and let the aluminum float to the top. Do it a few times. Work the crank around and make sure you get all the particles out. Make sure you drain all the mineral spirits out before you reassemble.

to check the cylinder..use a micrometer, they have em at most tool places..or take it to a local shop and have em mic it to see..or , some pistons are marked..look for numbers on it
 
Just take it to a machine shop and get it measured then buy ur piston based on what they say the size is. ebay is the spot for pistons. buy a wiseco forged piston. and if I were you I would just replace the crank bearing to be safe. you got this little project under control?
 
Hum...

Mineral spirits?Is there another name...never heard of that..

...After I rinse it is there any lube needed after that.thanks for all your help...I did not pay much for the bike so I rather try this.




Of course the best way is the hardest way. The only sure way to get it all out is to split the cases. But if thats not in the cards do this.

Go to Wal-Mart and get a gallon of mineral spirits. Should cost you less than $5. Fill up the crankcase and let the aluminum float to the top. Do it a few times. Work the crank around and make sure you get all the particles out. Make sure you drain all the mineral spirits out before you reassemble.

to check the cylinder..use a micrometer, they have em at most tool places..or take it to a local shop and have em mic it to see..or , some pistons are marked..look for numbers on it
 
the blaster head is a terrible design,re designing the combustion chamber would benefit him.The best thing to do is to have the engine builder cut the head,you will need the exhaust port specs to calculate compression and squish velocity(squish velocity is very critical),without this info your pissing in the wind.Typically engine builders dont like to give there info out(which is rediculious,but thats how most are)whats there # i may give them a call,really i cant see someone only charging you 30 bucks to design your cylinder head properly.
 
Thanks....

what fun it is.............thanks

Just take it to a machine shop and get it measured then buy ur piston based on what they say the size is. ebay is the spot for pistons. buy a wiseco forged piston. and if I were you I would just replace the crank bearing to be safe. you got this little project under control?