how to make a DL 125 faster

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1960split
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these may be stupid questions
i have a DL125 and its top speed only seems to be 47 mph(GPS).
everything is as standard will any of the following achieve a better top speed and cruising speed as the acceleration is ok

1) fitting a 42mm AF clubman exhaust

2) fitting a bigger carburettor

3) changing the sprockets to change the gearing

any help with the pro's and cons of these changes

thanks for any help
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RICSPEED
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not a lot ....do you have to stick to 125?
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fairspares
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all of your suggestions would work but the barrel would need at least a slight amount of tuning and the amount of tuning will determine what size carb etc you could use, tuning is opening the ports to get more fuel/air in and exhaust gases out , it still wont increase the top speed that much on a 125 , you would be much better off fitting a 175 kit or mugello 186 with at least a 22mm carb and upgear front sprocket ,this will give you around 60 + mph, but it all comes down to how much you want to spend .
Fairspares Lambretta workshop.
Wayne Miller
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1960split wrote:these may be stupid questions
i have a DL125 and its top speed only seems to be 47 mph(GPS).
everything is as standard will any of the following achieve a better top speed and cruising speed as the acceleration is ok

1) fitting a 42mm AF clubman exhaust

2) fitting a bigger carburettor

3) changing the sprockets to change the gearing

any help with the pro's and cons of these changes

thanks for any help

How fast do you want to go? answer that and then the lads will tell you how to get there :-)
Stay tuned..............
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corrado
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1960split wrote:
3) changing the sprockets to change the gearing
Definitely DON'T do that without any other mods.
1960split
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thanks for the replies

as for how fast i want to go

i want to get it sorted so i can ride at about 55MPH to keep up with modern traffic

i dont want to mess with it too much as it starts 2nd kick everytime and runs nice just seems to run out of steam in 4th gear

is it worth checking the jetting to see if this is correct

i was told it had a 150 top end put on it but cant confirm this

thanks for your help
storkfoot
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I used to have a 125 Special which has the same gearbox as you. When I bought it, it had a GP150 cylinder on it. It didn't like it, it just revved it's nuts off in 4th. So, if yours revs high at full throttle but doesn't transmit the power to the road, this may be your problem.

If it just runs out of steam in 4th, rather than rev, then you may just be expecting too much. The 125 Special/ GP 125 set up was meant to be a quick "about town" scoot and was geared as such. It wasn't a scoot you could stick on a dual carriageway at 55 ;)
teamsequipe
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Main scooter: GP200E Ron Moss Supertuned !
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RT 190
30mm PHBH
Remote Filter
GP200 sprockets
Decent 58mm Crank
Ron Moss Avanti exhaust

Cruise all day at 55 with no effort, up to 70+ for quick getaways

Ran a very similar setup last year, very reliable (after an exhaust change) and smooth to ride, lovely !
Old Lambrettas Never die ..................... they just go Faster !

Ron Moss says "Supertune it !"
soosh
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Total cost?
ricalnic
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Location: Livingston
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maybe you could look at what Kelly has done with his 125 Supertune
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