Scooterotica

hi , looking for input as to what exhaust and carb to put on 175 think its a af kit cheers

absolutely anything as long as you can get it to fit!!

Seriously though- what do you want the engine to do.........................?

its a friends first lammy, its got some sort of jimmy looking exhaust on it with the org ser 2 carb its very slow gos backwards up hill and good for bout 45 on flat rd so i was thinkig the exhaust and carb were killing it ?

Junk the exhaust for a start. Fit a later S3 type carb and either a standard or Clubman style exhaust. I wouldn't go mad.

I have an af 175 stg 4 on my series two did have a 22mm jetex and clubman. it topped out at about 45 -50 mph and was screaming. looked at the gearing and it was a 125 box giving a final ratio of 5.65 (I assumed it was a 150 box) changed to 16x46 for 5.3 with a stretched chain and transformed it. Pulls nice up long gradients and gets in the rev range nice (wouldnt pull a 17) have put a 28mm dellorto on open mouthed which gives it a bit more but has made it a little more revvy around town.
I suppose i'm saying check what gearing it has and what work has been done to the barrel they are a nice kit for what they are if matched right. IMHO
good luck with it

I've had a number of 175's over the years. Some were stock, some were tuned by me. I've done the 22 jetex and clubman a bunch. It depends on if you're going for top speed, rideablity, reliability, gas mileage(important for long distance), etc. 24 and 28mm carbs work good if you open up the ports properly. There's tons of expansion chambers out there.

The fastest 175 i ever had was with a 30mm PHBH dell'orto, and old west coast lambretta expansion chamber, mildly tuned by me, 125 head opened up to 62mm, but just the squish band. It looks almost like a center fired but isn't. The combustion chamber held 18cc. Stock 150 i tested held about 20cc. GP 150 gearbox with a 16 tooth front sprocket. Good acceleration, and cars had me clocked at 65-70 top speed. It was a spanish special barrel with the better transfer ports. Never seized it. Only had one circlip let go once. Lasted for a lot of miles, five years. Open mouth carb. Ran it til the bore wore out. My favorite one yet