Riding small scooters at top speed.

[klaviator]

I have owned a lot of bikes over the years.  I have run most of them up to top speed just to see what they could do.  I saw 147MPH on the speedo of my 84 FJ1100.  I only did that once.  I saw 130+ many times but only over 140 a few times.  Most of my other bikes were only run up near top speed occasionally but none were as fast as the FJ. 

My small scooters are different.  Running them up to top speed when top speed is so low is just a non event.  I probably see top speed on my Super 8 at least once a week.  That would be around 63-68 on the Speedo which I believe to be around 10% high.  I did see 73 once downhill. 

My Smax would do around 73-78 on the Speedo.  I did that fairly often as well.  My Sport City 250 would hit around 90 on the speedo.     Scooter engines are very mildly tuned so running them hard doesn't seem to affect them much although running top speed too much would likely shorten the engine life.  All of my scooters were perfectly stable at top speed. 

One nice thing about small scooters is that you can really run them hard without worrying to much about getting a ticket.

 

[CROSSBOLT]

Smaller parts, less mass, less total forces at max rotational speed. Model aircraft and boat engines sport max rpm around 12 to 15000 rpm!  Contrast with small ship engines EMD (Electro Motive Diesel) 12-567 and 16-655 typically max torque at 650 rpm with over speed trip set at 744 rpm. The trend is obvious. However, even with small engines care should be taken because the limiting factor is waste heat/cooling capability. I think most builders set the red line more by cooling limitations than anything. I agree with you on the point of shortening engine life but on Honda inspired engine designs, how can you tell?

[Stig / Major Tom]

I hope Kymco follows Honda principals......which seem to me to be "build a bullet proof engine first".....let others squeeze the last possible HP and speed out of the same CC's.
Over-engineer and under-stress ....that is what I want for my $$.
Many want more....that's fine. It's their $$.
My kids call me Capt. Slow for a reason.
Stig

[klaviator]

I hope Kymco follows Honda principals......which seem to me to be "build a bullet proof engine first".....let others squeeze the last possible HP and speed out of the same CC's.
Over-engineer and under-stress ....that is what I want for my $$.
Many want more....that's fine. It's their $$.
My kids call me Capt. Slow for a reason.
Stig

Pretty much every scooter out there, at least that I know of, has a mildly tuned engine.  I can't think of any that make even 100hp/ltr.  some sportbikes, including Hondas, make over 200 HP/LTR.  A 150cc scooter tuned like a typical 600cc sportbike would make 30 HP.  It could be made to be reliable but it would be very expensive.

[EvilTessmacher]

You know, that's almost exactly the reason I bought a bigger scoot.

I know that most of them worldwide are designed for, ahem, "smaller people". I have a good bit of beef on this carcass, so having a tiny little 153cc engine pulling my lard up a big hill on the way to work just didn't make sense. My initial look was at a Yamaha T-Max, but I eventually walked into my local dealer and found Diana. I reasoned that a bigger engine not straining was better than a smaller one straining.