Hello all, I have a Yamaha XV 750 4PW BJ97 where I refreshed everything somewhat before I drove it again after a long standing time. Now I have the following problems: At full load in the upper speed range no more power, at gas removal misignitions and white spark plugs. Air filter is fresh – intake I will test whether densely Keyster carburettor repair set carburettor synchronised New fuel lines tank checked and fresh fuel The only thing I n och habe: Since it is a V2 engine and the petrol tap membrane was somehow not dense I blinded the vacuum hose from the suction nozzle to the petrol tap and then drive with the position PRI (run through). After that I re-synchronized the carburettor like above. In the stand it finally ran a lot better and quieter but still the problem with the high speed and no more power… (from approx. 4.5 thousand revolutions no more power and only very slow turn up) U And when it’s cold and I activate the choke it jumps briefly on turns up and goes out again. Then I have to turn the stand gas screw very far in so that it gets temperature after eternal E-starter at some point and stays without Choke. I have Pro carburettor a 122.5 main nozzle (original) and the needle has only one position. And the mixture screw can not be set with running motor because no access possible / I have 2.5 revolutions outside of stop) I will order a petrol tap and restore the vacuum line, will make me smart how to check the ignition coils correctly and check valve games – more I can no longer think of what I can still do so that it runs nicely… floating positions I try to look at again and adjust if necessary and to exclude that he gets too much air sometimes with adhesive tape or similar to reduce the suction so that I can see if it then runs better (since to lean by too much Lu It can’t be that the flat sliders are opened properly by membrane and therefore they run to lean (I have traces of wear on one side of the flat slider and guess that the one depends and therefore not enough fuel is fed but with low to medium speed band there is enough power… If someone has a tip I would be VERY grateful! I’ll add pictures tonight.