Cam and piston arm ceasing up 55cc

simonsmurf

New Member
Mar 19, 2011
3
0
0
canterbury
i have nutted it down to the cam and piston arm ceasing up i pulled off the cylinder and head to find slight surface rust on the arm i preceded to try and turn the engine over using the flat screw under the gearbox cover it took a bit of crc and oil on the cam to arm joint i eventually got it turning however this is supposed to turn very easy and freely it requires about 15 -20 foot pounds

is their anything i can do short of dismantling the whole engine to get at the cam.

thanks zpt
 

2door

Moderator
Staff member
Sep 15, 2008
16,326
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63
Littleton, Colorado
Is this a two stroke engine? If so, they don't have cams. I'm not quite sure what you're up against here. Could you be more specific on what engine you have and maybe a photo or two would help explain.
Tom
 

Nougat

Active Member
Nov 4, 2009
1,332
2
38
Montgomery, IL
Presuming it's an HT two stroke, it sounds like you need crank bearings. This will involve splitting the case. You'll want to replace the crank seals and wristpin bearing while you're at it, and you might as well put a set of rings and cylinder base and head gasket, too.

But this is a lot of work and parts to put into an engine when you can probably buy a brand new complete engine for not really too much more. If it were me, I'd consider that motor a box of spare parts and just get another motor.

Of course, there's nothing wrong with fixing it up, either, if it makes you happy just doing it.
 

simonsmurf

New Member
Mar 19, 2011
3
0
0
canterbury
Is this a two stroke engine? If so, they don't have cams. I'm not quite sure what you're up against here. Could you be more specific on what engine you have and maybe a photo or two would help explain.
Tom
hi yea sorry its not the cam its the crankshaft
 

simonsmurf

New Member
Mar 19, 2011
3
0
0
canterbury
would rather rebuild for the joy of it

yes its a two stroke
aprox 2 years old ish (i have only owned it for a week :( )

it all looks in really good nick aye

i have heard that making it fuel injected can improve performance in general

as my target is 70kph im going to need every inch of power possible
world record for 50cc is 77.128,mph or 125kmh !!!

i have considered decreasing the size of the rear sprocket by making anew one
but have concerns about not having enough torque to pull the speed.