Hello to you all. I just want to show you some pictures of my stubmatching on my Runner 172. Original Malossi 172, and stainless stub from Scooter-Center. Before After And some porting of the cylinder. The casting must be opened equaly.
nice one john...i guess the engine is up and running by now. I remember when you started building it up on gilera runner.net Hows she go??? any recent pics or vids john
Hello Dave. Yes she has been running, but I have not got the carb set up correct yet, so I`m still working on this. Now its cold here in Norway, so I have put her on hold for now.
yeah its pretty cold here now john...i cant wait for the weather to start warming up in a couple of months....so much to do
What advantages is there to opening up the exhaust port? Wont you have to open up other area's to match? Why did you chamfer the edges of the cooling channels?
bigger port means more power but less responce.. also matched pipe works best with least wasted air.. what cooling channels? the part he ground is a transfer port feed..
i have had a stub for my 59 once that matched up perfect and others that havehad varying lips now thats quality control steve
not the stubs.. its the barrels 59 stub only matches in the tiny unmodded size it is anyway... pants tbh
If you use the stock exhaust, everything is ok, as this one has a narrower outlet that matches the small exhaust on the cylinder. But I did use the stainless stub from SC, and this have a much bigger opening, as you can see on the pictures. Original Tuning with no restrictions
those need alot of weld floated in them tho then ground back as its a rounded edge not a sharp flat cut.. will never match a rounded edge hence you have to grind them too big for any kind of power under full revs.
