Various ways of avoiding cutting rear runner...

[a.j]

When fitting an expansion on a S2.... Longer shock, suitable pipe, any pointers?

[Toddy]

You will find on most expansions the rear floorboard will need trimming even on the ones that are series 1/2 specific , I have fitted Franspeed, ADS and devtours all on mine with no real fitment issues apart from the rear footboard

[a.j]

I thought there might be some obscure pipe hidden in the depths of scootering that could fit without cutting. Oh well, bgm clubman it is.

[Adam_Winstone]

What about the various 'curly' options (e.g. JL Curly 3 or 4)?

[a.j]

I've heard they're not good and ground clearance is a huge issue, no?

[Shipleystevep]

If youre worried about cutting the original, i bought a repro about £30 and cut that one. Kept the original one intact.
(BGM clubman is good)

[barnsleybilly]

I had to cut the big lip off my nearside rear footboard too when fitting a Franspeed series 2 expansion.

[Monty]

I have a JL Curly fitted on the series 1 for that very reason. I have stainless foot board edges and didn't want to cut them up. Ground clearance on the curly is not that bad. I have to take care riding on and off curbs but that's about it. It's low on the centre line if that makes sense, My JL 4 down pipe was far worse and had to be welded several times.
Both needed trimming to clear the shark fin brackets and bolts.

[Donnie]

Most expansions will have the ground clearance issues, never seen one that isn't.

Despite having had a couple of JL's and a taffspeed copy pipe and cutting a good section of my S2 floor board, i've just "fitted" (ground, fought, persauaded, bodged, dremelled, teased, sworn at and finally secured) a tsr evo and have had to grind even more off.

However, this may well be because I have had to fit a shorter shock due to the manifold of the gt kit touching the frame :-/

But I would echo if you want expansion chamber without cutting, jl curly pipe is the way to go.

[olliewtf]

or if you wanna go old school, underkickstart fresco!
Not the best for all out power but look great and sound like a spitfire.