small drivetrain gear shear

[Elixys]

hello everyone, recently got my second build put together 66cc skyhawk, and was running extremely well for the first two days....middle of the third day on the way back home from work, the small gear on the crank case side popped a chunk of itself and the woodruff key attached to it right on out. luckily i had my spare motor to salvage it's gear from.....why do they insist on making these parts out of cheap aluminum? everyone should know that aluminum is only good for beer cans and mail boxes. *sighs dejectedly*....anyways got it all back together without too much trouble...wish i had a digital camera...would take a picture of the little bugger and post it to the forum.....was fun fixing it though....gave me a reason to yank my hair out.

 

[MotorBicycleRacing]

attached to it right on out. luckily i had my spare motor to salvage it's gear from.....why do they insist on making these parts out of cheap aluminum? everyone should know that aluminum is only good for beer cans and mail boxes.)

The small drivetrain gear is machined from steel
try putting a magnet on it....

 

[biknut]

Mine is also steel. Look at the bright side, at least broken in half it was easy to remove. I recently had to replace mine because if excessive wear. I bought a couple of spare pinion gears from Spooky Tooth.

 

[Elixys]

non magnetic........im telling you its made of aluminum.....the big gear is definitely hardened steel its a completely different color from the small gear.small gear is the same color of the outside of the motor and is obviously made of billet aluminum......even took a sanding drill bit to it with the dremel....no sparks shooting off.......just powdered away.....im telling you its aluminum.

 

[biknut]

The ones I bought were $6 each. Make sure you have the special tool that removes and installs them.

 

[Elixys]

by special tool you mean flat blade screwdriver, ball ping hammer, and needle nose pliers right? because thats what i used to install the one from the old bike to the new bike.

 

[biknut]

My kit came with this nifty tool that acts as a kind of press to remove and install the pinion gear. I think it also works for removing the drive sprocket too. I believe you can buy them.

 

[Goat Herder]

non magnetic........im telling you its made of aluminum.....the big gear is definitely hardened steel its a completely different color from the small gear.small gear is the same color of the outside of the motor and is obviously made of billet aluminum......even took a sanding drill bit to it with the dremel....no sparks shooting off.......just powdered away.....im telling you its aluminum.

Would like to see a pict of it and know where ya got it from?

 

[biknut]

by special tool you mean flat blade screwdriver, ball ping hammer, and needle nose pliers right? because thats what i used to install the one from the old bike to the new bike.

Drop the hammer and put your hands up. Now slowly back away from the bike.

 

[epicboy]

the special sprocket pull tool works on all the things on that motor that need it..

 

[breno]

sure does all 3.
Make sure ya locktite the sucker back in and if need be make up a flat shaped piece of metal that fits perfectly and attach a shifter to retighten ya dont have to go overkill but I find it just makes it that lttle bit easier for undoing and retightening without burring it up.

 

[Elixys]

if i can get access to a camera i will take a pic of it and post.....got the kit from gasbike.net.....was the grubee skyhawk 66cc regular 149.xx ....and a big duh to me because i have two of those sprocket removal tools but didnt know how or what their purpose was....still dont know........big flat blade screwdriver got the one out of the old motor with some gentle prybar action and copious amounts of WD40 (old motor is parts motor now anyways) and the woodruff key slides into the groove from the back (closest to the crankshaft and slides forward into the proper position.....then putting the gear into the new motor was a cinch with a little help from a pair of needle nose pliers, laying the big flat blade screwdriver on top of it evenly, and gentle (and i actually do mean gentle this time) tapping with the hammer onto the screwdriver slid right into place like it belonged there....