Wico Flywheel stud repair

[Ricks]

As many of us have experienced, many of the Wico flywheels have had the pinion gear stud holes stripped.  I recently bough a bike that had the pinion gear holes drilled and tapped to 5/16, using bolts and not straight.  There were no cracks in the keyway, so a full center replacement like Wayne performs was not necessary.  I have used the EZ-Lok inserts before with excellent results, so I decided to do it again.  I drilled out the holes to 5/16" on a drill press and tapped them to 3/8-16.  I then installed the inserts, which come with thread locker already on them.  I feel that this type of repair should last almost forever.

PS: I know the package says to use a Q drill, but I like the slightly smaller 5/16" drill in the soft Zinc flywheel.

[pd]

Looks like that'll work , Rick .

I've read some good reports about EZ-LOKs .

Pete .

[kartjockey]

Those are nice because they only require a normal tap to thread the hole with. (unlike the Heli-coil set-up) There is also another brand called a "keen-sert".  Which are the same but small pins attached vertically that are driven down between the treads to lock into place.  A home run either way!

[pd]

Keensert :



Personally , I have only used Helicoils and have had good luck with them .

Pete .

[Ricks]

Thanks for the picture PD!  I have never seen those before.  You machinists know about all the cool stuff out there!

[kartjockey]

if you ever try these make sure you get the small driver with them.  It is about 3/16" in diameter and has a small dimple in one end to stay centered over the pin.  Then you can drive straight down on the pin.  If you use just a hammer you will bend the pin every time.

[carryall]

Thanks for sharing those products.  Learn something new everyday (try to at least)  Both those are great options for those "oh crap" situations vs the Helicoil.  Is there a preferred vendor for them like Enco?