Make 125 go 5mphish faster

[Lalababa]

Hi everybodie ! Unfortunately I am not in a position to ride more than à 125 atm. I have ridden most of the older carbed 125s, in almost all road situations. I'd say most if operating well could hit the 60mph relatively handy esp. Varadero and shadow.And this speed is adequate enough for 60mph roads etc. However some 125s can only struggle to 60 and may become abit hazardous on a long busy stretch of 60+ road. Also if a headwind or hill.
I really like riding the gn125 but then again these can sometimes struggle to 60.
So it would be a great improvement to increase the top speed (by 5mph?) of these carbed 12hp ish bikes....ybr, cbf, gn,cm,el,gz,..etc.
Has anyone here managed to do this? And how did you do it? And how did it work out?
The more simple + cheap examples I've found on the net are: hiflow airfilter with larger main jet and needle raised,coupled with a hole drilled in exhaust.And/Or front sproket down one tooth.
I'm not interested in losing weight or going 150cc bore.
Also I'm thinking of getting a cm125 (probally post around 1990 ,as I think earlier ones were just over the 15bhp rule)
and I wondered if ye have any thoughts on these and what is their top speed?
Cordially yours,
Lalababa.
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Lalababa

[WD Forte]

Go on a diet if you is a fat boy.
Power to weigh ratio like innit?
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bikers smell of wee

[MarJay]

5mph is a huge percentage. You really would be better off just buying a bigger bike.
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British beauty: Triumph Street Triple R; Loony stroker: KR1S; Track fun: GSXR750 L1; Commuter Missile: GSX-S1000F
Remember kids, bikes aren't like lego. You can't easily take a part from one bike and then fit it to another.

[Lalababa]

I'm not fat just BIG BONED!
I can't get a bigger bike as I'm stuck on a 125.
I could just get a varadero or shadow (bit more expensive aswell)but I really like the gns or maybe à cm with straighter bars. I'll probally get a 12hp bike and do à bit of tinkering.
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Lalababa

[Lalababa]

Oh another mod I've heard would be to put a small windshield. What do ye think?
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Lalababa

[Ste]

[WD Forte]

As well as power to weight ratio there's wind resistance.
I've read that after a certain speed, most of the power from an engine is used just to overcome this.
Think about the mad speeds cyclists can achieve when riding close behind a pace car with a wind barrier.
Racers tuck down behind a fairing too, so they're not used just for looks are they?

As most 125s are regulated to a certain power output, getting an A2 licence at least would open up your options
and most of us seem to agree it's money better spent than going in the bigger piston 'moar powah' route.

Even if you were one of the few folk who could tune a 125 engine to the max without fucking it up
The frame, suspension, transmission and brakes were not designed or built to handle it so there could well be consequences.
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bikers smell of wee

[WD Forte]

OR
buy a scooty

My Deliveroo guy tells me his Forza and PCX 125s would do 70
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bikers smell of wee