Piston rod bearing keeps breaking

[DAMIEN1307]

Ahmet seems like a really sharp kid.

He is a sharp kid, but i do know that things are not very plentiful for him as it would be for us...He has to do a lot of "Just make do with what ive got"...DAMIEN

 

[Karl Snarl]

He is a sharp kid, but i do know that things are not very plentiful for him as it would be for us...He has to do a lot of "Just make do with what ive got"...DAMIEN

Thats what I'm saying. Just a piece of scrap metal, an the two tools and bits, and he can make a manifold spacer. Find a saw in the trash ( I pull things out of the trash, don't you dare think I don't. lol. On man's trash is another's treasure. One idiots trash is a gold mine for the smart one. lol). People buy far to many simple things they could have made at home in a few minutes.

 

[Street Ryderz]

ahmet, i have to ask, do you have any access to power tools? you would need a drill, and a grinder/cutter for what i have in mind to get rid of those jetted carbs. you should try a pumper carb/ diaphragm carb. they are used on chain saws, weed eaters, etc. Get a chain saw one for about 30 usd on ebay. or if you are low on funds, try a cheap 12 usd one from a 43cc-49cc pocket bike. the pocket bike carb only has one adjustment screw besides the idle screw. the chainsaw ones have idle, and hi and low adjustment screws. no changing jets, just turning a screw 1/8th turn at a time. You can make a simple spacer manifold to mount the saw / pocket bike carb on your engine. its easy, one big hole, and 4 little holes, 2 tapped to the thread of the screws you want to use. sounds way more complex than it is. its basically make spacer, mount carb, go ride, turn screws till it runs how ya want, while you are out riding. no more coming back home to spill gas everywhere and ruin gaskets changing a jet. really makes is super easy to tune. I got tired of smelling like gas and only use pumpers on my new builds. only have one bike left with a nt carb. an its only on there because by god i spent a month tuning it to perfection and refuse to screw it up by changing stuff on it. lol


edit:: and that one bike with the nt carb, is my trail beast, and when i had it set up for speed, it would do over 63mph( i never found it's top speed, when I seen 63.9 mph on the speedo, I got scared and back out of it, that and the road was beginning to curve. never went that fast again, i stay below 50 mph now). I've since detuned and changed gearing to make it top out around 50, but still pull away from a dead stop no pedaling.

LOL your speedo is whacked there is NO way ever you did 63mph with an nt carb! what's the rest of the setup?

 

[Street Ryderz]

As I read through the post I'm left confused as to what bearing is having an issue as the poster said the bearing between the crank and rod which is the big end bearing and if so how did he change it not having tools to do so ? Regardless any bearing failure on the crank or the wrist pin is usually form the improper timing and trying to rev it higher than it should beating on the bearings firing too early. In most cases detonation would occur if this was prolonged then just exaggerate the issue, compression or octane is not the issue as these are not high compression engines even when highly modified. The cheap china bearings don't help though, I agree they should be replaced with quality pieces right from the get go! The next would be crank balance as some are very bad and this again contributes to bearing failure's through out.

 

[DAMIEN1307]

As I read through the post I'm left confused as to what bearing is having an issue as the poster said the bearing between the crank and rod which is the big end bearing and if so how did he change it not having tools to do so ?

Im sure hes got the basic tools but when he didnt have a spark plug gap tool, he used a screw driver creating a 1mm, (.040 inch), spark plug gap...That wasnt helping matters out at all...lol...DAMIEN

 

[Karl Snarl]

LOL your speedo is whacked there is NO way ever you did 63mph with an nt carb! what's the rest of the setup?

Was a custom made 5 speed cassette, with a jack shaft double sprocket( one for low end and one for high end, an of course the driving sprocket), bored the nt throat, made my own slide to fit, custom intake, custom exhaust made from a dirt bike, ported all to hell and back for high rpm, used an old dirt bike cdi, all i know is it was honda and older than dirt like me, head had a custom shaped conical flat top chamber, etc, etc. I have since scrapped the jug, didn't like it. was a big turd till around 5-6k rpm, then it jumped on the pipe and scream till gear change. an the gps was spot on ( =/- 1mph), it has been tested with many vehicles speedos. all which happened to read the same thing tested. $80k ford truck speedo, yep read the same, rousch mustang, yep same test, same result, gps was accurate. took me a year of tinkering to make that sucker scream, then again I really don't get a lot of free time. got tired of crap parts and started building my own, then i wanted to see just how fast 66cc could take me. I found a 66cc engine will take me way faster than i care to go not on one of my motorcycles. I'm not worried about if you believe me, I could careless to be part of some " good ol' boy" club. I did it for me, and I happily exceeded my wildest goals.

 

[DAMIEN1307]

Was a custom made 5 speed cassette, with a jack shaft double sprocket( one for low end and one for high end, an of course the driving sprocket), bored the nt throat, made my own slide to fit, custom intake, custom exhaust made from a dirt bike, ported all to hell and back for high rpm, used an old dirt bike cdi, all i know is it was honda and older than dirt like me, head had a custom shaped conical flat top chamber, etc, etc. I have since scrapped the jug, didn't like it. was a big turd till around 5-6k rpm, then it jumped on the pipe and scream till gear change. an the gps was spot on ( =/- 1mph), it has been tested with many vehicles speedos. all which happened to read the same thing tested. $80k ford truck speedo, yep read the same, rousch mustang, yep same test, same result, gps was accurate. took me a year of tinkering to make that sucker scream, then again I really don't get a lot of free time. got tired of crap parts and started building my own, then i wanted to see just how fast 66cc could take me. I found a 66cc engine will take me way faster than i care to go not on one of my motorcycles. I'm not worried about if you believe me, I could careless to be part of some " good ol' boy" club. I did it for me, and I happily exceeded my wildest goals.

That wouldnt seem overly unreasonable to me with that many modifications made...obviously more money into this type a project than you would ever make by selling it...they call it self satisfaction and a labour of love...lol...DAMIEN

 

[Karl Snarl]

over $400 in just bike chain alone. lol.

 

[DAMIEN1307]

over $400 in just bike chain alone. lol.

You are not a cheap date, are ya...lol...DAMIEN

 

[Karl Snarl]

oh im a cheap date. just slap me and I put out. lol. My hobby's aren't cheap though. Lasers and motorize anythings with less than 4 wheels. lol. Lasers cost the gdp of a small country sometimes.


edit:: I actually got rid of my fleet of bikes because I have a bunch of engines laying around. Not kit engines, but alkinds of lawn stuff and garden stuff. was gonna start making new rides. Then the flood of bikes came in, and the corner is once again over flowing with motorized bikes.