ruined Phelon flywheel keyway and crankshaft repair

[Scooter4]

Good evening,
Has anyone repaired the Phelon flywheel hub keyway? Or crankshaft?

I earned the fool of the year award because I only tightened my Phelon flywheel about half way to measure headlight coil amperage and about a minute later found that is not enough to keep from ruining the keyway on the flywheel and crank. I did not tighten it all the way because I knew I was going to be taking it back off.

I am disappointed it did not shear the key, but instead rolled it.  The key looks good. Maybe an aluminum key would have sheared. The crank and flywheel are very soft compared to other things I have worked on. 

I have not ever repaired keyways, I have always been able to easily make and replace the metal part that is damaged or buy a new one.  Not sure if mig welding or brazing the crank would be best and then cut a new keyway.  I know the shaft could be replaced, but would probably attempt to fill it in and cut a new keyway.

The flywheel really concerns be because trying to replace the hub and get it trued back up looks like a problem, but cant be used like it is.
Please let me know.
Thank you,
Scooter

[Ricks]

That’s a mess.  Brazing the keyway has zero chance of holding up.  I worked on a motor that Gary Wollard had tried doing just that, and it failed immediately. 

If you have a lathe and a mill, mig or tig would probably work.  The other option is send it to Wayne, he can replace the shaft with a new on.  He can also put a center into the flywheel.

[kartjockey]

There is a great amount of the keyway left in the flywheel to identify its location.  If you were to machine a copper key to fit the slot and secure it in position, you can then fill the missing voids with weld.  Remove the copper key and clean up welds.

I have heard of people using graphite keys.  Then brazing.  The key locates the flywheel.  The taper holds it.

The crank is another story!  Not much of the original key slot left but maybe enough to get the job done! 

If you have the means just get busy.  It's only steel!

[pd]

My crank wasn't as bad as yours . I tried different things , but , nothing worked until I welded the keyway .
I hand filed it to proper shape , but , a dremel rotary tool would have been a lot easier .
Anyway , no more sheared keys and no more key wobble .

I would think the same could be done to the flywheel .

Pete .

[Scooter4]

Thank you all for the replies.
It is good to know Wayne does repairs.  At least I have that avenue available.  Would be cool to live near him and learn.  I have made many complex repairs for people, but it is so rare I use any form of electric welding I have to beg a buddy at work to do it.  I even own a tig for years I have never used because I almost always gas weld.

Great idea on the copper key.  That would make restoring the slot much easier.

I am going to take a crack at rescuing the parts and if that does not work then contact Wayne at least about the hub replacement.  I am concerned about it because it is deformed so bad.  I will have it apart this afternoon and clean up better to check.

I still cant believe it happened because I had the nut fairly snug.  I held the flywheel with a chain wrench, but I know I did not tighten fully.  I only ran it just above idle, and within one minute of running and taking my amperage reading the engine was slowing down so I though the I needed to idle it back up but before I could reach the throttle I heard rubbing sound on the flywheel and knew it had come loose and before I could reach the key the flywheel locked up on the laminates and I bet that is when the key rolled out

That is a clock I wish I could turn back.  Certainly a change in project plans.
I will let you know what happens with the repairs.
Thank you,
Scooter

[Ricks]

Here is a picture of the crank that Wollard “fixed.”  It looks like he also tried to peen the material to tighten up the keyway.  It lasted about 10 seconds before letting go.  Wayne made a new shaft and used the old counterweight.  Interesting counterweight on this crank, Gary drilled it and added heavy material.  I think that helped smooth out the engine, as when I built this motor, it ran really smooth and strong.

Last picture is with the new shaft.

[Scooter4]

Thank you for posting the pictures.  That replacement shaft looks great. Is it welded on the other side of the counterweight?

I got everything apart. I checked the flywheel before I took it apart and was surprised it runs true still.  I am going to have them tig welded since I have access to a professional. Very grateful for that because my electric welding ability it terrible.

I am also going to lap the flywheel and crank.

I made a copper keyway filler for the flywheel.  Dont know when I will get the parts done. 

Thank you,
Scooter

[Ricks]

That one was silver soldered. He now tig welds them. Silver solder is expensive.

[Scooter4]

Good evening,
The bike is running again.  A welder welded both parts for me with MIG, but I had to redo the flywheel with stick because he was not able to see in there.  I machined and lapped them.  I was planning to spend hours hand filing the flywheel keyway, but realized I had a hacksaw with a deep enough throat and could stack four blades.  When I was setting up in the vise, I realized I could use a piece of plywood that needed behind the flywheel as a guide if I cut a slot in it.  Took 10 minutes and made a very nice keyway I had to file about .005" wider to fit the key. I made an aluminum key for it.

In the process of putting it back together I found what happened.  I forgot to put the washer behind the gear nut and the gear had heavy rust damage to the unused threads and made me think I was tightening it.

I almost did the same thing on the repaired parts, but this time I was checking fit up and making sure there is enough thread because it ends right at the flywheel and now my flywheel is a little further on the taper from the repair clean up and lapping.

I ran it for a while and checked and seems to have stayed tight.  Also used blue thread locker on the nut.

Thank you,
Scooter

[Ricks]

Well done sir!

[pd]

 Gotta love it when a plan comes together .

Pete .

[Scooter4]

Thank you all.  It was way too much work for such a simple mistake.
Scooter

[pd]

Thank you all.  It was way too much work for such a simple mistake.
Scooter

Ha . The work was your 'reward' and insurance against you making the mistake again .

Pete .