Sym xs125 speed?

[Halthelittleb...]

I’ve bought a Sym 125 as a write-off - bent handlebars, smashed stuff…
I’ve fixed it all up and went for the MOT. On my run home I cracked it open to see how she did. New speedo in KMH but happily reached 140. This is about 85mph? Is this possible?
Yes, I am mad.

[Easy-X]

A decent 2-stroke could manage it no problem but a Chinese copy of a 30+ year old Jap 4-stroke engine? 65mph is a more likely top speed. Either it's the wrong speedo or something's up with the wheel gear/sensor.
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Ste]

The new speedo is saying that you're doing 140kph (which is 87mph) because of how wildly inaccurate it is.

You're actually doing about 60mph.

I recommend you get one that's more useful.

[that_impulse_guy]

99% of the 4stroke copies will do between 90kmph and 95kmph true speed. Thats all shes got.
i.e...somewhere around 56mph. gives or takes. Indicated could be anything.


just want to add...if you did (or previos owner did) a 150cc kit, lt230s cam, "speed exhaust" etc....then perhaps 65mph.

and as anybody can figure out , all those mods just arent worth it. 85mph isnt going to happen
edit: just looked up pictures of your engine...its the yamaha clone by the looks of it, so the above mods dont apply, but the theory does.
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