We were poking at this derbi my buddy picked up a while ago and noticed a curious bit.
In the intake, there was this little aluminum ring. It looked like the top hat in a monopoly game, except there was a hole in the top. I think the inner diameter was like 9 or 10mm, so it was obviously a restriction.
I am wondering if this is normal, or if there was a derbi model that is castrated and not fastable, like a PA50 that sucks major balls and is a hassle to make fast.
If there are other restrictions, anyone know what and where they are? Is there like a system of rating, like a sachs with A B C and D or the puch 1 1.5 or 2 hp or the motobecane or peugeot ratings? If so, how do I tell what it is?
It is a 1980 variant sle in case that helps.
Thanks in advance.