moped 101 questions help?

[mrmoped2012]

I originally wanted to get a 100cc or 90cc bbk on my moped but i was told that really all i can get is either a 72cc or 80cc bbk

is that true?

was recommend to upgrade the carb and get the 72cc bbk over the 80 because of the longer engine life which i want so i did
(is in shop right now)

i have a 2012 50cc renegade have had it for a year and not one problem at all runs great (have kept up will oil changes and store in the garage)



i want to get my moped going form 30-35 mph to 45-55 mph hoping that the 72cc bbk and carb upgrade should do that by itself right?

how much speed should i get form a 72cc bbk and upgraded carb?

putting on a bbk do you have to do any machining or dose it just fit the cylinder?

adding a racing cdi seems easy and cheap will it get me a boost in
speed? and are there any negative effect that come with it?


where is rearing , rollers or weights?

how do i adjust them or add new ones to make a moped more like a motorcycle?? and is it hard??
(what i mean by that is faster take offs or higher top speed)

[skuttadawg]

A 72cc is less risk in damage as a 8x or larger can stress the crank and have a higher compression . I had a " secret 63 cc " and upgraded to a 50mm or 82cc BBK which had way more power on takeoff and uphill but had the same top end . I could get to to speed and maintain it easier than with the 63cc engine .

To get more power a BBK is the best way . To change the speed you will want to try changing out the weight of the rollers or opt for a gear swap which is not so easy as changing out the variator weights . Its hard to have fast takeoff and top end its more like ether or and I prefer to tweak the midrange . You can install 1k , 1.5k or 2k clutch springs so the clutch engages at a higher RPM in order to take off faster or pop a wheelie . Now if the RPMs are not redlining or close to it when you top out on level road lighter weights can allow the RPMs to be more and gain top end as well as takeoff and midrange . If the RPMs are screaming at top speed on level road then a 1 or 2 heavier will help with top end but too heavy will hurt take off and uphill.

Most stock CDIs are not rev limited as they used to be and I read where some had a hard time starting with a racing CDI that had advanced timing . I put a racing CDI on my 2T takeoff was a hair better but the exact same top end .

With 10 inch wheels it is so unstable at high speeds compared to 13s or 16s so it was like stunt driving to me and more skeery that when I hit 160 MPH on a CBR 1000 .

You can get every HP part and still only be able to go so fast and the more you push it the more likely it will fail and not last as long as the cheap parts are not race quality .

If you really want a fast small scooter your best bet is to sell your 4T and buy a 2T as they easily will outrun a 4T stock and with a BBK and pipe really go much faster

[mrmoped2012]

thanks for the advise my main goal is not to make it a race moped or soup it up like crazy just want to go at least 45 mph and take off quicker so i can keep up on the road!! but being able to pop a wheelie would be cool if i can make it do it!

so the cdi is worth a shot? only 20 bucks online

and ill talk to the guy doing my bbk about the weights gears and rollers to get a price

what was your top end speed with 82cc bbk though?

[skuttadawg]

The speedo said 55 MPH + but was really 45 MPH . You will need a new carb as many are sealed , have too small of jets and some no needle clip to adjust the needle position .

Some BBKs reuse the stock 40mm or 49cc head which will have a high compression but smaller combustion chamber and valve size compared to a 50mm head which would flow better with a Uni or unrestricted exhaust . I have seen many who drilled two holes into the muffler and had better flow and was upjetted