Yamahappyuk

hello guys , well i took the inline fuel filter out of the equation and low and behold this was the problem ! ( i didn`t understand that fueling was so critical , the filter was choking the motor at higher revs ) , i will look at the front pipe when i have time , Lotherton Hall Show on Sunday 29th so we`ll see how she copes with a lengthy 70 mile " A road " run , bye for now ~ Pete / Lanc`s .

thx Phil but you missread my question i think , the pattern barrel is in the skip , this was a recent copy and i did not want to run it so i pinched my proper Yammy barrel from the other bike i have , the bike will not rev past 6/ 6500 even with the standard sprockets 15 / 49 so gearing is not the issue . i will start by removing the inline fuel filter i fitted , possibly look at crank seal demise ? ( although she is not burning any engine oil ) , someone has had a look at the electric rotor side so i will investigate further in this area , i will find the problem eventually as there are only so many things it could be ... thanks for your time in replying / Pete .

I have recently aquired another DT which had a few amateur "restoration" issues >, engine oil in the 2 stroke tank ! , copy part barrel and head , seized suspension pin ect , anyway i have been through all the bike swapping some parts from my other DT which is undergoing a total restoration ( i have never run this bike yet ) , this has included a yamaha barrel rebored 1mm over with Mitaka piston , all new carb internals bar the floats plus rubber joints and yamaha filter and new cables all round , i have reset the clutch arm to cable so there is now some free play and checked the float height 3 times as someone had put a big fat copper washer underneath the needle valve (which i have now replaced with the proper part) also swapping the oil pump , the bike starts and idles and seems to be running well on the road , not smoking excessively and pulling well in the Low / Mid range) i have ran in the new bore for 500 miles and recently added one more tooth to the front sprocket but she still struggles to rev past 6000 / 6500 , any advice would be welcome , Pete / Lancs .

Motul 5100 semi synthetic 10 / 40 `s is very good , i have used for 70 000 miles , just keep changing it and give her a new filter every now and then , the motor runs very hot which is normal ...

OK thankyou