another potential engine killer!

bairdco · #1 03-10-2010, 10:33 AM

i don't have a bike to build right now, but i've got a brand new Grubee Starfire GT4 66cc, so i figured i might as well clean it up and blueprint it.

when i took the head off, there was a piece of aluminum the size of a fingernail clipping sitting on top of the piston.

it was a piece broken off of the bottom threads from the spark plug hole.

if i woulda run that motor, it wouldn'ta run for very long, unless i got lucky and the piece blew out the exhaust.

didn't take any pics 'cause my batteries were dead, but i think you can understand what i'm talking about without them.

i suggest, if you don't do anything else to your motor, at least pop the head off and check. you can clean up the last few threads with a file, and save your motor's life.

ZRTMWA · #2 03-10-2010, 03:52 PM

I could hear a piece of welding shaking around in my exhaust when my kit came. It took a while to disassemble, shake out, and reassemble. Not as deadly to an MB as those spark plug shavings though.

bairdco · #3 03-10-2010, 04:06 PM

yeah, a chunk in the exhaust wouldn't do anything except rattle, unless you did a back flip with the engine off and it fell into the port.

Bikeguy Joe · #4 03-10-2010, 05:16 PM

I was amazed at the amount of metal shavings/dust/grindings/chips I found in the first engine I got. I have been taking them apart and cleaning everything every time. That includes the clutch and mag.

A can of brake cleaner goes a long way, unless you guys in California can't have that stuff.

bairdco · #5 03-10-2010, 07:11 PM

i use carb cleaner, more or less the same thing, we can still have that. i haven't looked for brake kleen in awhile.

i was amazed at how hard it was to find a good clear coat paint, though. tons of the cheap stuff, but the good toxic paint is all getting banned.

ZRTMWA · #6 03-10-2010, 08:09 PM

Quote:

Originally Posted by bairdco

yeah, a chunk in the exhaust wouldn't do anything except rattle, unless you did a back flip with the engine off and it fell into the port.

Oh good thing I cleaned it out then, this MB is gonna be my stunt bike

Bikeguy Joe · #7 03-11-2010, 04:45 AM

That was funny.

oldspeedsi · #8 03-22-2010, 10:14 PM

I have found it to be a good idea to take the top end apart just to see you will always find something you don't want in there and you can clean up the ports wile your at it.

Sign Guy · #9 03-23-2010, 08:38 AM

Seems like we should just buy a Honda engine and be done with it. Yeah it'll cost a lot more but if you are having to tear down and rebuild and replace darn near everything on these little motors then you aren't really saving anything IMO. I spent about 2 weeks of evenings tearing apart and cleaning/replacing bolts, etc on my engine to make it last longer, etc. I am hoping to get 100-120 mpg and hit 35 mph without having to spend tons of time and effort to get it done and it shouldn't be an issue on a 66cc motor... Sorry for the rant, I guess it's just one of those days.....

**BarelyAWake** · #10 03-23-2010, 08:55 AM

It isn't an issue if yer simply wise enough to read past the advertising hype and not expect a bolt n'go fer a buckfiddy lol

The whole point of this forum as I see it is to give ppl a "heads up" and advice regarding the particularities of these el'cheapo kits, with a lil research and some basic preparation there's nothing wrong at all with these engines - it's ppl's expectations that often lead them astray and leave 'em disappointed.

What so many fail to realize is the engine itself should also be considered a kit - if yer not willing/able to spend a lil time tinkerin' during it's initial setup and replacing some of the shoddy parts included "free" with the kit...

Then yea, defo buy yer way outa the "problems" - but I'd recommend just gettin' a moped as even a Honda on a bicycle is a bit of an abomination, the bicycle itself going to need constant maintenance, repair & parts replacement.

*shrug* Ifn ya don't like to tinker - don't motorize a bicycle lol