I've been working to get my '87 Lario running properly. When I bought it, it had a Rennsport exhaust that looks good and sounds terrific but doesn't seem to do much for its performance. I think its gigantic tubing diameter doesn't match well with the limited breathing ability of the stock engine: the bike quickly runs out of breath and goes flat at higher RPMs, and I note that the stock exhaust has a restriction at the cylinder head.
I have a stock exhaust for it, but the carbs have been rejetted for the Rennsport. I have been able to get stock size main and pilot jets and needles, but the needle jets are proving to be a problem. My Dellortos have the accelerator pumps incorporated into the needle/main jet assembly, with needle like the one at the top of the photo:
http://s655.photobucket.com/user/sthomag/media/Needle-jets.jpg.html?sort=3&o=0The only replacements I've been able to find are those like the bottom: obviously for carbs without the accelerator pump.
The stock size needle jet is 168. The size the bike came with is 165. Can anybody tell me where I can find an appropriate replacement? Or should I turn down the long needle jet to fit?
By the way, the cam has been replaced with the wider lobes, and it's got a new valve job with Nevada springs.
