Those butterfly shaft screws...

[Chuey]

One slip and it gets expensive.

I used to work at a pro level bicycle frame manufacturing company (Masi). I was a filer. Every file stroke was made on a frame that I could barely afford, in other words, I took it seriously. When trying to get me to file with some confidence, my Italian bosses used the word "courago".

I say hit those little mofos, not too hard, with some courago. It's part of the process and it's all about "process".

How have you peen lately?

Chuey

[Garnet]

One slip and it gets expensive.

I say hit those little mofos, not too hard, with some courago. It's part of the process and it's all about "process".

How have you peen lately?

Chuey

My memeory is a bit hazy, but I don't remeber it being as difficult as everything that I had read. I seem to rember that I just tapped down the exposed thread on one side of the screw, much the same as it was done by Bing.

I deffenitly remeber thinking That was easy! when done.

[ME 109]

I was going to suggest peening Doug, but that Chuey got in there first...... again.
Damn he's quick.

[dougie]

I just bought those 2 shafts.
I decided that hammers and punches are not even allowed in the same room.
If properly snugged screws work in Oz, they should work even better right-side-up.
(and Loctite 243 - see new thread).

[Chuey]

Damn he's quick.

That's what she said. Oops! no. That's not what I meant.

What I meant to say is that so few people peen. It's fun, it keeps things together and it sets one apart. And it wasn't made by someone else. One has to peen for himself.

Chuey

[ME 109]

and it sets one apart.

I may be seen by some to have over done it in that regard (think valve seats)

[Duane Ausherman]

Peening a valve seat is another whole thing from those shaft screws. One will work and the other won't....... not for long.

[ME 109]

Peening a valve seat is another whole thing from those shaft screws. One will work and the other won't....... not for long.

Long enough though.

9 months of regular riding after the eh-hem peening, the seat was as done with no visible problems. (besides centre punch marks)
Of course it's not the 'done thing' peening heads, but when yer 900 k from home with a head that had been repaired twice after 'the initial incident' yer gonna peen it.

Who would have thunk having the valves around the wrong way would take 8,000 k's
plus a sustained 180 kph to make itself known.
I know my bike well, but I didn't know the valves were ass about! Same performance.

A rather costly experience actually... hey but I won't do it again.

Inlet valve after doin' time in the exhaust port.


exhaust valve in the right place. valve seat 'made' to stay in the right place.

[Duane Ausherman]

I have also done a few onerous repairs to get home.

So it came apart because the valves were swapped in position, not the peened seat? That just isn't fair.

[ME 109]

We probably all have moments in our lives that we are not proud of. 'One' of my moments was putting the valves in one head the wrong way around.
Inexperience, not concentrating, not taking heed of warning signs.
But what was done, was done. And it was the start of an expensive, frustrating lesson that cost me about 2,500 by the time I bought two s/hand replacement heads and had them reconditioned by an airhead machinist.

Two heads?? the second head let go the exhaust valve seat as well, quite some time after the first. Why? Dunno.

That is why I pulled the wrong head off at a bike rally. I knew the sound of a valve seat that had come out, so it was only natural to suspect the head that had been repaired twice after the wrong valve in the wrong hole incident....
When I pulled the suspected head off, I found that the previously peened seat was sitting there as it should (except for the peen marks)
Damn! wrong head.

So, you guessed it. The second head was also peened...... because I made the decision that these heads were no longer viable.....and I had to get home.

It must be two and a half years since the 'new' heads were fitted. All is very well, and stable clearances.

My photos are more like Halloween pics than Chrissy pics.