Folding Bikes - suspension seatpost on a Downtube?

Does anyone use a telescopic suspension seatpost on a downtube? I have a bad back so I need some suspension, and my back doesn't like the rearward movement the Thudbuster kind, I need the telescopic (pogo) style. I'm also not interested in the dual suspension model.
I see that dahon sells an extra long, telescopic suspension seatpost, but I'm guessing the seatpost diameter is different on the downtube.

If the seatpost diameter is 27.2, I might be able to find a standard suspension seatpost long enough to use on a folder, but i doubt it.
thanks in advance

Pogoing seatposts' efficacy is doubtful at best. The movement that is absorbed by suspension posts is precisely in the direction that the Thudbuster is designed for.

If you ride over a bump with the rear wheel, the frame rotates around the front wheel's axle. The movement at the saddle is up and forward. Pogoing posts do it up and backwards.

So perhaps you need to think carefully about the geometry of what you are after. Backs are too valuable for mistakes. :)

I've had telescoping suspension seatposts on all my bikes for years. It's what works best for my back so I'd like to stick with it. So I'm just trying to find out if I can get one on a Downtube. thanks

I've had telescoping suspension seatposts on all my bikes for years. It's what works best for my back so I'd like to stick with it. So I'm just trying to find out if I can get one on a Downtube. thanks

The various Downtube models have different seatpost diameter sizes. My 2007 Front Suspension and VIIIH models came with the 27.2, but the Mini and Full Suspension comes with a wider seatpost.

You'd have to make sure you buy a suspension seatpost that's 500mm long. That'll be hard to find.

Another possibility is to take the wider stock Downtube seatpost, cut it, and insert a short 27.2mm suspension seatpost, then put a seatpost clamp on it. I think that's been done before and discussed on this Forum.

Actually, if you have a bad back, what you really need is the Downtube + Cruzbike conversion. Like this:



With optional child seat and child:

You guys look like you're having a good time!

Anyone know the seatpost size on the FS?