Last friday we went to the circuit de Croix in the north of French.
Saturday it was the whole day free practice so we could test our bike on the circuit and let my son get used to the bike.
It was cold but dry and there were 8 sessions of 20 minutes.
Because of the cold there were many crashes, the french riders are crazy , cold asphalt and tyres and still going if they had to win a race.
Our bike ran very well and my son got more and more used to the bike.
He never raced on a classic bike with drumbrakes , but every session he was going faster.
But starting the bike for the sixt session, the bike was making suddenly a lot of noise on the right side in the cilinderhead , immediately we put the motor off.
Taking of the valve covers we noticed that from cilinder four , the rockerarm of the inletvalve had a big clearance.
But the nut and screw were still locked , it was not possible to push in the valve.
Probably there was something with that valve.
So end of the day for us , we packed our things together and went home.
Today we took off the cilinderhead and noticed that the inletvalve was stucked in the valve guide, but there was no further damage.
Only a little touch of the piston by the valve.
It was no oil problem , plenty of oil in the head .
We went with the cilinderhead to our tuner to find out what went wrong.
He had to press out the valve, the valve was not bent, but on the stem there were scratches with another type of metall in it.
Looking in the valveguide there was missing some metall in it what was now on the valve stem.
We examined all the valvestems and valveguides , they had all light scratches.
Then our tuner told that he had used valves with a litlle thicker valve stems as usual by our engine.
Probably was that the cause.
He promised to fix it as soon as possible and we trust him.
We have still three weeks to go for the first race.