Tuning Troubles M50 Need Help

[underdog]

My Benelli M50 has the following mods : Mod cycles 70 kit , Arreche 19 mm , pilot 20 , main 95 (came with 60 to lean) , needle set on bottom groove . (tried upper and middle) . Br8s plug , Mallossi White Contra spring , Jasil Blue Clutch springs , 6 gram rollers in stock vari , with stock muffler mod . Cut restritor (that rolled up metal wrap on the end of the inlet pipe) .
Doesn't seem to respond like the stock carb and kept seizing with the stock Leader carb even with 35 pilot , 95 main , needle 1 up from bottom . Even with a leo zx it seized . Premixed @ 50:1 . Even seized @ 32:1 . Would like to get it tuned with the stock modded exhaust . Or a recommendation for the correct pipe for this set up . Please reply . Thanks, underdog

[underdog]

The leo zx pipe I had purchased did not fit up to head . Had to modify . Stock modded pipe worked better except for some gain on the top even after the clutch springs and 4 gram weights . Pipe never seemed to work right .

[jmkjr72]

are you sure its a 19 the 17.5 comes with a 60
is the kit al or cast iron if its al try a 9
are you running an air box or an open filter

[underdog]

Arreche part # 819/16 . Cast Cylinder . Stock air box . I added an additional stock type snorkel from another box 1 1/2 " up from bottom of box to vent . I tried a open air element back to back with the vented box . Overall the stock vented box was best .
Thank for the speedy reply . Getting fed up with this scoot . My previous Zuma worked better . underdog :banghead:

[jmkjr72]

thats the same carb i have for my lcz and the jetting is what i figured it should be
cast iron so the plug shouldnt be too hot

are you useing true arreche jets or one of those knock off sets on ebay i havent heard good things about the ebay sets

i would suspect you might have an air leak some where

[underdog]

Has factory Arreche jets and new stock intake pipe . Original had cracks . Dissassemled because of low copression . Even with a soft seize it always damages the piston , rings , and cylinder in my experiences . Going to install my Ruima 70 kit when I pick up the gaskets today . Start out fresh again . This kit has already been broken in . It was from my Zuma . Installed a Hoca 12mm pin piston and rings after honeing and ran a short time . Then tried the current cylinder and had failure . Hope It works good . Hopeing to get this thing running right with the stock modded pipe I have .
If I were to get a better suitable pipe what would be good for this application ? Thanks for the input .
jmkjr72 .

[90GTVert]

The reed/intake is notorious for leaking on these. I don't think I've ever put one together yet and not seen a leak there with a pressure test without using some type of sealant on the gaskets or in place of gaskets. Might be worth checking if you haven't.

[underdog]

Did a pressure test today with my other 70 kit . No leak . Went over the air box , sealed the rubber coming out of the Air box , installed a better clamp to carb and even for a test I placed a thin strip of duct tape where the Air box halfs meet . Tried the needle in all position . Seemed to work best on bottom groove . Still doesn't run right . Any inputs would be nice :-

[90GTVert]

Bottom groove is the richest, so it's likely you are lean. Maybe try a pilot between the 20 and 35 and adjust the idle mix and needle position afterwards again.

You said you disassembled it because of low compression, but what's the compression like now? If compression is high, maybe from tight squish, it will build up heat faster too. As long as your exhaust isn't clogged or restricted, you should be fine. I've been riding a 90cc with a stock 49cc pipe, so the 70 sport stuff should work OK.

Not sure what oil you use, but if it's not synthetic, I wouldn't use 50:1.