30 bhp whats it feel like

[Avantone]

Please dont take my vega leggies away......

i dont mind going slower if i look good!

[RBG]

Please dont take my vega leggies away......

i dont mind going slower if i look good!

We all look good on a Lambretta and going slow just lets everybody have a good look!

[156 D]

This is interesting, where was in sourced from?

It was something I posted about aerodynamics on the old forum - The curves show the relationship between power and speed when trying to overcome wind resistance. i.e. to double your speed you need 800% more power.

I could never understand why people fitted vega legshields from a performance point of view on racers (apart from the fact they look wicked sorry Dan )

http://www.phpbb88.com/scooterotica/vie ... tica#12319

I think it’s fairly well accepted that compared to modern day bikes and scooters, Lambretta’s (and Vespa’s) are pretty brick-like and heavy which makes getting significantly better performance both difficult and expensive.

I’ve also been thinking for a while, how fast a standard engined scooter could go with the benefit of some wind tunnel modelling. Now the challenge here is to do something that helps the aero profile of the scooter whilst still retaining it’s clear identity.

If you go down the power route to increase speed, doubling the maximum speed requires an 800% increase in power!



I’ve based the table above on the power required to increase the top speed of a 65MPH/11HP scooter. As you can see, to hit 90MPH needs an almost 300% power increase.

Wouldn’t it be easier to improve aero dynamics? (Mostly talking racers here for the purists). We see cutdowns, but does that really help? It generally doesn’t improve the frontal area, and actually hinders the way airflow is managed round the rider.

So any thoughts? Any budding aerodynamicists out their? Anyone want to lend me a wind tunnel?……………….

Below is a chart which is almost identical to the 800% extra power needed to double your speed....if you divide the 80mph speed bhp of 3.0 by 800% you get exactly equal to 40mph speed bhp of .37 .... but i think this may help as it goes further and quotes BHP per sq.ft. of frontal area.....so one may be able to work out extra items that stick out into the airflow......such as your upper part of your body ect.,.....one other thing that you have to take into consideration is Rolling Resistance?........

Although taken from one of my old 1949 published sports car tuning books ....i don`t think the resistance of the atmosphere has changed that much in 60 yrs so the actual figures would still apply.....

[cezeta]

thanks for the explanation, its a depressing insight into how slow our scooters really are. i have a 19.5 bhp ts1225 in a series1 which back in the 90s was the fastest of anything i had ever ridden (scooterwise)

the reality of it only being a 70mph scooter and only 5mph faster than a honda 205 or indian gp with pipe and carb upgrades is horrifying.

can you do a new graph that plots ££££ per mph

no wonder frank sanderson and fattspeed are gaining demand.....a bit of steel conduit, few blob welds and dump in rd500 gamma motor or a husky thumper.

i feel cheated

[rbgaz]

bit like my mates who thought their ts1 were doning 90 plus till i gps our ride outs and said no its 73 mph (they still wont av it lol an my gps is wrong lmcf !! ffs

[davidblythe]

Fastest scooter down our mad mile is 83mph GPS and a lot of scooters have gone down it now

[rbgaz]

well i recon this standerd 200 55-60 ts1 70-75 rb22 maybe 80 and as ive read on another post rb20 90 !!! lmfcf

[rbgaz]

p.s what engine done the 83mph dave?

[davidblythe]

my TS1 and dryballs ts1 230, my RB in not quite as quick, feels quicker due to the way the power kicks in

have spent hours working on the ts1 and it is a better all round kit in my opinion, but the RB does make me laugh on a Sunday afternoon down the lanes

agree with your summary of speeds most TS1's are in the region of 70 to 75mph, have seen them slower than this

[cezeta]

whats the spec on your grubby ts1 david?