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Discussion Starter · #1 ·
guys...

i currently own a small scooter suzuki AN125....

it's a 4-stroke 2-valve 124.5cc

it'll do bout 65mph tops...

but recently i changed the bore to a 152cc and really gave a "whoof" to the tourqe, a quite impressive midrange... a 5hp bump from the previous 11bhp....but....oh, there's a but....

the thing is it's now stuck at 55mph...i've just lost 10mph on my scoot..!!! everything else is stock....i just needed the low-end power and mid-range pull...i'm...ahem...big.

everything else is stock...including the exhaust...but i did change the air filter to a freeier flowing one....and that's it...

how can i get back my 65mph....that's all i ask....a bit more i won't mind...but no less....well maybe 60mph is good enough...

regards..
 

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8 Posts
Discussion Starter · #2 ·
i guess nobody here knows a suzuki AN125 huh....?? :confused

but i explained quite a bit....any experienced guys/gals out there might be able to help...??
 

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Big bore needs better air flow both in and out. Get a pipe to match the cylinder and I think you will see improvement. The danger here is getting the fuel and air mix right, but on a 4 stroke it is not as critical as on a 2 stroke.

So with that said the changes needing to be made for a big bore kit to be effective are:
1. more fuel/air in at the right mix(might require rejetting the carb or replacing the carb).
2. more exhaust out.

The company/shop that sold you the cylinder should be able to help you determine the setup necessary or they shouldn't be selling the parts.

Rob
 
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