Small frame for touring - beginner questions

[jakem]

Hi,

I’ve currently got a 125cc Modern Vespa, which I took from England to Italy and back in 2023.

My 125cc modern Vespa has 11hp, and tops out at 60mph. I need level ground and no wind, or a slip stream to maintain 60mph, but I don’t get any higher than this as it hits a rev limiter. It also has averaged 150mpg, and I’ve had a high of 230mpg, so range has been great on the 8 litre tank.

I am however becoming drawn to building up a small frame, and had a few questions.

I’m looking to modify it and need it to exceed my current Vespa, but as I’m looking for longer tours, top speed is important. Ideally I’d like to be able to maintain 65 and maybe hit 70mph, but still have decent reliability / range.

1) I’m 6’ tall, will I fit on a small frame?!

2) With a kit of around 130cc, would I be able to maintain 65mph?

3) What sort of fuel economy / range could I expect from a 130cc tuned small frame? I see a larger tank is available but takes up the tool kit area.

4) The primavera side storage compartment would be great, but I see some exhausts curl round and fill this whole area. Do these exhausts massively improve performance? Or would I be best to go for the storage area?

[clampett]

This is my opinion as I'm not an expert.
You should probably increase to a 250-300 for cruising at those speeds.
High speeds like that on a 150cc bike is only going to wear it out and possibly be spitting oil out into your air filter.
A 300 can cruise at the 65-70 all day with no issue, but you won't get near that mpg. Maybe around 70.
Anything under 250-300 is going to slow down on the inclines. Basic physics. Gotta have power to move weight.

[jakem]

Thanks. During my longer adventures, I wasn’t sitting at maximum speed for hours at a time. I’d avoid motorways, and stick to country roads but could have say 6 miles (10km) between some roundabouts / turns, which put some more focus on top speed than acceleration.

I lose a lot of speed on hills at the moment, but I just want to know if a small frame could be a step forward.

[henri]

i was 6'2" ,with age more like 6'1" nowadays ,an do fit on a smallframe ,but even on large frames always sit far back on the seat.
to cruise at 65 you will need more than 130cc ,at least 144cc if not more .an even then your talking about sustained periods of near maximum revs/stress ,a tuned engine isnt best at that . an will return very low mpg an need regular servicing an rebuilding .
one option is the egig 170cc engine ,that will hold 65mph all day long when set up right .but there not cheap i'll warn you ,i'm just about to build some for 2 guys . starting with nothing,so new cases an engine internals etc ,the kit/crank/etc all add up to a component cost of just over 3k .H

[jakem]

Thanks for the reply. What would a 130 get me hp wise and speed wise? Peak and sustained? Will it hit 60mph? Or more like 50?

[mark]

My DR130 Kit would sit comfortably at mid 50's and peak at about 61 MPH but wouldn't keep it that speed constantly ( Henri fitted and it served me well ). I had just fitted a new Polini 130 and was running it in before a car wrote it off !
I didn't get a chance to put it through its paces but it seemed very responsive , only took it up to 60 MPH but had plenty left to give . 59 MPH on GPS about 69 on speedo ( wildly inaccurate )
As Henri said 144 cc may be a good bet but I know bugger all , sacrifice a few MPH for reliability / fuel economy . No matter what speed you will always arrive in style on a small frame.

[jakem]

Jan 23, 2024 12:42:16 GMT mark said:

My DR130 Kit would sit comfortably at mid 50's and peak at about 61 MPH but wouldn't keep it that speed constantly ( Henri fitted and it served me well ). I had just fitted a new Polini 130 and was running it in before a car wrote it off !
I didn't get a chance to put it through its paces but it seemed very responsive , only took it up to 60 MPH but had plenty left to give . 59 MPH on GPS about 69 on speedo ( wildly inaccurate )
As Henri said 144 cc may be a good bet but I know bugger all , sacrifice a few MPH for reliability / fuel economy . No matter what speed you will always arrive in style on a small frame.

Thanks, the DR130 sounds pretty much identical to my modern 125cc 4T Vespa. Sitting comfortably at mid 50’s but with a peak around 60.

I met an Italian couple last year who had bought a PK50 for 1500€, fitted an 80cc kit and then had ridden 80,000 miles (120,000km) through Europe and England, often two up! I didn’t get a chance to ask whether the engine had needed much work during that mileage - but it did make me question what sort of adventures would be possible on a small frame.

[mark]

I had a lovely PK50s which I still regret selling.
It came from Wales and engine done by Taffspeed ?
Had a Malossi 112 kit on it and it bloody flew in a scary way.
The old PK seemed very light and I didn’t weigh as much then , it was hard keeping on the road when cornering at speed 😀