i recently got a new top end and reed block on my zip but since i got it back it only does like 35mph and feels weak as anything it has a leo vince tt, 17.5mm carb with 62jet , 5.5g rollers and polini belt could this bethe new top end wearing in or something serious?
I'm no expert on zips but the main jet seems small to me and she could be running lean. Check what standard is and you should upjet by about 10%. Also find out what roller weight is standard and look at some lighter weights. A new top end will be a little tight but it will loosen as it runs in
