Dude, if you're going this far with it...I'd just bite the bullet and do a re-build. Hey, look at it this way; now if you want, you can build some compression ratio into the motor, do some head work and maybe get a few more ponies out of the Baby G. Don't you just love it...that little bike and this forum?

C.......

I tried to hang myself, but I'm too tall, so I started thinking. . .

Self, you need new pistons.  Maybe 74 mm pistons?  Probably not.  Depends on the cost of machining.  

Self, you've got the head there?  Make it hot!  Can I clean it up with the Dremel if it isn't warped?  

Self, you've got the carbs there?  Clean them!

So, I guess the question is, aren't I doing a re-build at this point?  

Waiting on parts now. . . I love that fact that the DAMN THING RAN AT ALL for the past couple months, and actually felt pretty fast at times!  I'm bummed that it is needing to be re-built, but that is why I bought it.  But I'm stoked that I know what needs to be done to fix it (read: everything).  

The scary thing is, neither me nor the mechanic detected any knocking or unusual sounds.  Just SMOKE!!!!

how bad are the cyl? and the outside of pistons? if not SCORED BAD and the feeler gauge doesnt say excessive amount of room, might get away with stock rings. slap? sure its not a rod knock or even the CB shaft bearings starting to go?  stock pistons are 73.6mm or some odd number to fit 74mm bores. your next size up would be 74.25 ish? for .5 overbore and 74.8 for like 75mm bore  making it 1.0mm overbore  (working on cheap source of pistons as i found cheap rings already for 75mm)  numbers shouldnt be toooo far off as i was guessing.

The piston and the rod are screwed.  The cyclinder is cool though.  

Ohhhh. . . I thought the stock bore was 70 mm.  Ahhh.  My bad.  

I just want to get it back together and go for a ride.  The sooner the better.

Ummm..ok whos telling you you need rods?! and pistons?! or did you take it all apart?

If your going this far, might as well go all out and get forged pistons, bored etc... and go for performance. :mrgreen:

Quote from: RashadUmmm..ok whos telling you you need rods?! and pistons?! or did you take it all apart?

Read the last post on the first page.

I've got the cylinder off.  It needs a new rod and new piston on the left side.  There is no doubt about that.   The rod is probably okay, but the bearing is screwed, as is the piston.  

I'm not going to get crazy with 78 mm pistons.  I'm already going to spend about $250 for parts, maybe as much as another $100 for machining, depending on whether or not I need to mill the head (haven't really looked at it yet).  

Since I'm probablygetting a new bike this fall, I am just going to put it back stock.  

Set out to clean carbs. . . ended up re-building the entire engine!  I love it!

Quote from: dgyver

Quote from: RashadUmmm..ok whos telling you you need rods?! and pistons?! or did you take it all apart?

Read the last post on the first page.

oops!

Parts total for re-build:

$330.00.

Having no idea what you're doing:

Priceless.  

I'll keep you guys posted.

Dgyver, the 78mm piston change looks impressive. Do you know if compression heights are the same for the GS piston and the Wiseco piston? Just lovin' the little scooter and this forum...wish it would quit raining awhile so I could play.

C.......

C.....Is this what you are asking about: Piston Pics

I was just wondering if the pin c-l to crown deck is the same on both pistons. Will the deck height be the same...with stock rods. Love the Baby GS and this forum.

C.......

think i reconise that 79mm piston.

I think ive got a crank that spun one rod and might have and extra stock piston, ill see if i can get out early tomorrow and dig around.

hey blue, if you don't I have a extra set of pistons with pins but no rods.

Quote from: Blueknytthink i reconise that 79mm piston.

Actually no. Yours is in my motor. That is a third one I found.
Now only to find a fourth....

 IT IS! you never told me how it worked out.


Davipu, havent been able to get into my shed as of yet. still trying, been rainin abit down here

Is the compression height the same with the 78mm and the stock pistons, using stock rods? Still wondering if the deck height will be the same. Love the little bike and  :kiss:  to this forum.

C......

Well, looks like several people are interested in fitting higher compression pistons in their Baby. I still wonder if the compression height is the same and is dome configuration such that no machining is required. In simple terms, which pistons will bump compression with no machining (other than boring). Love the Baby G and this forum.

C.......