Ok, i thought my whole kit went south awhile back. Today i got the box back down and was looking through it to see what i needed to get to get my **** back in running order. I was looking at the piston and the little ridges that run around it actually broke...anyone else have this problem??? also...where to i get a new piston and rings??
thanks,
-matt

 

well first of all I have not heard of these little ridges breaking? but it depends on what kit you are running. i know that you can get a takegawa piston and ring set from many distributers like www.crf50racer.com
www.xr50.com
www.hondaminitrail.com
or contact the distributor you bought the kit off of
for stock check out www.dratv.com

 

if i remember correctly, you bought that kit from me. i have never seen a piston break like that. if u need another shoot me a PM

 

i'll shoot you pm later on, and i'll take some pics and post up later....

 

piston...what do you think went wrong??? cylinder still seems to be fine??

 

damn, looks like it could be one of 2 things.. either you ran it out of oil, which i doubt is what happened, or that was caused by detonation. those TB 88s with the stock head have a ton of compression. i cant stress enough on how important it is to run high octane gas. im not blaming you of anything but, theres tons of kids around here that run these kits and think its ok to run 87 octane in them. they ride around all day with the thing pinging like crazy and they act like they dont hear it or it doesnt matter. a rev box or a timing mod in conjunction with low octane gas can and will be fatal to one of these kits. post some pics of the top of the piston if you can.

 

pre-detonation is a motherfukkkkkkkerrr

 

What about a dirty airfilter?????????? That can be a huge problem with 2 strokes

 

How high of an octane are you talking? Highest at the pump or some 104+?

 

when i got my 88cc i still had 87 in it. then i got the high grade pump gas (93?) and the pinging almost stoped. only get it for like the 1st minute of warmup.

 

93 is minimum i would run in it. now thats for a stock head. race head you could get away with 89 or 91 prolly

 

here is the top of the piston

 

well like fab said use high octane, I got my kit and it wouldn't run all that great, matter fact it wouldn't run worth a damn on 87, i went and drained it and the carb, put 94 and it is great.

with a superhead and pipe I don't know. prolly stay with 94 to be safe.

see that whitish spot, unless you wiped the top, looks like it kinda got a lil on the hot side.

 

anybody got an xr70 head??? i might buy one before i order this piston....

also, is it worth it to port the 50 head???

 

50 head compared to a 70 head is incredibly small, i wouldnt waste time porting it

and to add to the thread, all we get in california is 87/89/91, you 94 ****'s are lucky

 

and on the way to new mexico awhile back we were at a gas station that had 86/ 87/ and 90

 

91 good lord. im definately puttin all my money on detonation.

 

ya, i was running 100 av fuel for a while, but whenever that ran out, i started using 91 or 93...there's only like two stations around here that carry 93...

 

An octane problem you would probably see more damage on the top of piston such as distortion and or holes melted through. I'm running a takegawa 88 kit and I think spec. was 12:1 or something to that effect, so i don't run anything less than 110 octane. As far as the piston, it looks like the ring wasn't in all the way when the cylinder was put on. Don't know if you have tryed to put it together or not, but were the piston is broken it looks to clean to have broken when the engine was running.

 

yes detonation can cause damage on the top of the piston as well as a connecting rod. but, it will take its toll on whatever is weaker. in this case, the ring lands.

a takegawa 88 with stock head is 11:1 and will run all day long on 89 octane without a single ping. running a higher octane than what is needed is pointless.

a piston ring can only go in one way. there is no "half way" or "all the way". either its in or its not.

not hatin bud, just tryin to clear some things up.