please help, 50cc engine wont start

hokumra · L Plate Warrior Joined: 13 Mar 2008 Karma :

hi, i have a 50cc malaguti f15 firefox and the engine died a couple weeks ago, the small end bearing shattered and took the piston etc out with it Sad

i have bought and fitted a new piston, cylinder and rings, and they appear to work ok, the piston travels up n down the cylinder smoothly etc, but it i can't get it to start

it looks as though there is no petrol getting thru into the cylinder, i have stripped and cleaned the carb and the petrol is going into the carb, but it has not made any difference on making the bike start.

can anyone shed any light on anything else to try.

thanks in advance

seth

ms51ves3 · Super Spammer Joined: 08 Jun 2007 Karma :

Have you checked you have a spark and do you have compression?

Robby · Dirty Old Man Joined: 16 May 2002 Karma :

It depends on where the bits of small end went and what they did.

I'm not familiar with this engine, but if it uses reed valves (and it probably does) I'd check the reed block to see if the reed are broken. The reed block sits between the carb and engine, set into the crankcase.

ljwalker · Nitrous Nuisance Joined: 19 Jan 2008 Karma :

starter motor maybe, spark plug Very Happy

hokumra · L Plate Warrior Joined: 13 Mar 2008 Karma :

not checked the compression yet,

tried 3 different spark plugs and they all seem to have a nice blue spark, replaced the reeds on the reed valve. the engine also turns freely on either the starter motor or kick start

3/4 of the bearing stayed in one bit, some was down the exhaust and the rest was under the big bearing.

i'm pressuming its something to do with compression but not sure what controls that other than the piston rings? but they are new aswell.

i've checked the gaskets on all the bits i replaced and they all seem to be fitted correctly