Date: Sun, 9 Jun 2002 23:28:31 -0400

How to fix a TX.

Las year I drove the engine of my TX 750 over the hill. It was capable to
make a smoke curtain big enough to hide the Bismarck. Blast!

So it was time for a complete engine overhaul. At least new oil scrape
rings on the pistons.

I managed to get the engine out of the bike and loaded it into my car to
go to Yvon. Yvon lives on the other side of the country. As you
understand it is a long drive. Begin a Dutchman, going to the east border
(where Yvon lives) took me a 3 hour drive!  Yes, it is a long way.

Anyway, Yvon took the engine apart. I merely helped him, carefully
watching every move, and now and then giving tools like a surgery
assistant.

He thought me how to disassemble the rocker bay properly with his special
home made tool. We took the camshaft chain of with a grinder. We made
sure that nothing fell down into the engine, by tying everything up with
copper electricity wire.

 We found out that both the pistons had jammed (only slitghtly) in the
cylinder. Oil scrape rings were scrap. Big end cups were gone and small
ends had too much room. Valves were more or less ok, we thought. Later I
was told by the restaurator that they had too much room as well.

Al was done in a couple of hours. After that I took the part home to
start the restoration. I took the parts to the engine restaurateur in
Haarlem, the city where I live.

That man (and company asked me not to mention his name as he does not
fancy more of these jobs) is known for his expertise. Extra ordinary guy
that restores Bugatty's, Spykers, Aston Martins, Deusenbergs, Ferrari's,
Delahyes and so on.

As Yamaha, both the Netherlands and Japan could not supply me with de
necessary pistons, and piston pens. Neither could they deliver me the
Big-end cups.

It took a while, but in the end we had some nice solutions. The
restaurator found pistons from a fiat 126 (Kolbenschmidt 92050610) witch
matched the original. They are a wee bit lighter, which is good.
He modified them by inserting the valve spaces and shortened the bottom
of the piston to give it the necessary room for the moving connecting
part (forgot the name).

He did magic with the valves and its shafts. Put bronze bushings in the
small ends for the piston pens.
The big ends cups were trashed. Yamaha could not deliver. We used Renault
4 engine big end cups that were slightly modified.

Finally it was time go get the stuff and assemble it again. I took al the
stuff to Yvon and in one day we managed to assemble the engine and get it
into the bike as well.
We were short on time on the end of the day and my battery was too low to
get it started.
Got home and charged the battery, set the timing of the ignition right
(and switched the cables of the ignition)  Broooom, the engine came
alive!!!. Smooth running engine and no smoke!
Happy now, very Happy.

Greetings from Holland. There is one more running TX 750. And its mine.

Hope to see ya one day.
Whenever you're over here, you are welcome.

Herman Postel                
Zwiepseweg 151                                   
7241 PT  Lochem                            
0573 - 251816                  
e- mail: hpostel@dds.nl