thanks to you all ,guys!
I think 'I'll use a basket ball needle as JVS told me And anyway if I kill them by overinflation it won't be a big loss as I think they are a real bullshit !My dealer ,as the bike is still on guaranty told me it was my fault as I often ride with my wife!!!! My previous 300cc 1990 MZ had 90.000miles ,never changed the absorbers .OK ,I don'expect the same from the Bullet but 4000miles.....!
Thanks Greg for your offer but I live in France,It's a bit far from Nevada !