So I have an unwanted el-cheapo full susser behind the shed and wondered if it could be made into a fun chopper. The bike is the typical y framed dept store style with triple clamp forks, and ideally I'm looking for a chopper with this kind of shape:

http://www.instructables.com/files/deriv/FMV/BBG8/DEWEP27ZTFP/FMVBBG8DEWEP27ZTFP.MEDIUM.jpg

The only thing I'm concerned about is if I keep the rear suspension in place whether it will create too many 'bendy' forces on the whole thing?

I'd probably leave most of the frame intact, as I've not got access to many tools, and just extend the triple clamp forks and move the saddle as far back as possible...

off the top of my head the frame is kind of like this:

<deleted as i found a pic of the actual bike....>

Ya dood. ANYTHING can be done. I've done the same thing with a smaller-framed full suspension bike and it was a lot of fun. If you dampen the rear spring a lot it makes for a really fun, bouncy ride. I don't think you'll run into too many issues except maybe extending the existing fork. They don't like to be welded (learned this the hard way) so you may have to get creative. You could replace the existing fork with a stiff one and shove a stiff, small diameter pipe up inside them and then into the tube of the suspension fork. It's hard to describe what I'm talking about but it's along the same lines as what you might do with a tall bike to conect the steering of the two frames, minus the second frame. Hope that makes sense. As far as setting the seat back further, I've seen people chop BMX handle bars in half, making sort of an 'S' shape, and shove the middle half into the seat tube to make an offset seat post. It seemed to work ok. Your results may very.
Hope that helped.

Cheers Blais - this is the exact bike, except mine is missing the front wheel at present...

http://www.djcycles.com/catalog/images/PromotiveGreyds500.jpg

siiick. That will make a cool chopper.

Here's a triple suspension chopper (http://www.rat-patrol.org/RPOz/FArt/zedsDead.html) I made (pre-paint job) for a race where Rat Patrol Oz kicked arse (http://www.rat-patrol.org/RPOz/rides/24hr2006.html):

http://www.rat-patrol.org/RPOz/images/FArt/zed/PICT0008.jpg

Oh, and here's anothery (http://www.rat-patrol.org/RPOz/FArt/sproing.html) (post-'paint job') made for the same race.

http://www.rat-patrol.org/RPOz/images/FArt/sproing/PICT0066_72dpi.jpg

Because of our suspension choppers, we are much tougher than Johnny Payphone or any of you punks:
http://www.rat-patrol.org/RPOz/images/rides/24hr2007/PICT0049_72dpi.jpg

This is a dirty attempt at a mock-up:

http://farm4.static.flickr.com/3262/2615225639_49715cde70_o.jpg

So the plan is to just extend the forks, compress the rear suspension loads and then fit a nice comfy saddle and ape hangers. Any comments?

This is a dirty attempt at a mock-up:



So the plan is to just extend the forks, compress the rear suspension loads and then fit a nice comfy saddle and ape hangers. Any comments?

wow that is going to be one wild bike :)

I think your fork tubes are welded to your bottom yoke


if they arent it would be easy to slip longer tubes in there.

one other possible problem is that your seat is right over the rear wheel, and you have rear suspension. you will need to make sure you have enough clearance for when the suspension compresses. no matter how far you tighten the rear spring, you will have suspension action. maybe not now, but as the spring wears out you will start bouncing. so clearance is important.