Down under, an idiot and a 400F

^^ Agreed. Those look slick!

Been wracking my brain about how to get more clearance with the pipes on lean. I think the problem is the straight sections of PVC pipe I'm using with sharp bends. I could go to have them made but I don't want to risk not getting it right given they'll probably set me back $150.

I need a way to replicate gradual bends in PVC that the tube bender can copy. Anyone have thoughts?

Would be good to try and bend the PVC pipe as 1 complete piece using a standard shape (paint tin maybe) to keep curve consistent.

Anyone with thoughts on that? Doesn't need to be exact but I would rather:

1. Get it right in $8 PVC pipe than get it wrong in SS
2. Get the clearance I need now between footpeg and rear tyre with shock compressed
3. Hug the swingarm a little more as it's going to be a bit flatter in reality, not the steep angle where it's at today

You can bend pvc with a heat gun. Don't concentrate the heat and be patient, waving the gun over a few inches of the pipe.

Great. An excuse to buy a tool too. Been wanting a heat gun for a while anyway for heat shrink.\

edit: Just watched a video... why on earth did I not think about that before. Would have been a million times easier than cutting and gluing!

Mmmmmm …

Maybe PVC + heat gun can solve a problem for me - could you link me to the video?

Crazy

https://youtu.be/7QqVm7wsqXA

Looks simple and even appears to bend under its own weight.

Thanks neevo!

Crazy

This is quite easy to do, but it is a little tricky to make accurate bends with small radii in larger (2") pipe. It helps to make a pattern or template on a flat surface with lines for the inside, outside and centerline of the radius you want to bend to and some straight entry and exit lines to align the pipe to when bending. PVC gets very rubbery when warm enough to bend and tries to flatten out and kink with tight bends. The flat surface will allow you to squash it back into a round shape by hand (wear a welding glove or use a wet rag!) while holding the pipe to the template. You can make a fancy form but this works well for me. If you are going to reproduce the pipe on a fancy mandrel bender you have some options. You can simply cut and miter and glue the parts together. If you make a pattern for the radius bend you want and cut and miter the pipe to fit it, you will be able to translate that to the bender and get a smoothly bent version as long as you know the radii and the distance and axial rotation between them which is easy to do if you mock up with straight elements. You'll have to estimate your clearances around the curved parts but that should be pretty easy.

Nice project man, keep it up! I almost read the entire thread this afternoon. Personally I think the seat is a bit of a let down to the rest of the bike. But that's just my opinion. I really like your creative solutions!

Sent from my E5823 using DO THE TON mobile app

Fill the pipe with sand, tamp the sand and put unglued caps on the ends. Have a sponge and bucket of water handy to quick cool the pipe in shape. There's also a tool called a pipe viper, but it's not cheap. It's basically a long spring that you order per diameter of the pipe.

Great idea Mr. irk!!! Maybe it's an old trick, but I never thought to try it on PVC. I've made some extremely convoluted pipes for marine sanitation over the years and I will definitely be trying this out!!

Mobius; The stainless tube will be done by a proper tube bending company who have a CNC bender, so getting the template is really for them to measure up and program the CNC off. So really all I need to do is get an approximation of what I need in PVC before giving it to them. Thanks for the tips re the PVC bending. I think I will use a wooden panel to draw up the angles and try and hand bend the PVC to that first and see how I go. Might also see if I can find something with the right radius that I can bend around (paint tin maybe) to keep all the radii consistent. Only $8 per tube so if it goes wrong I'll just buy another one. Keen to get these pipes as accurate and perfect as possible before they get sent out for manufacturing.

So maybe make a few bends with a template so you can control the radius, and then cut them to the degrees of turn you need (you'll need that info for the cnc bender) and connect with the straight bits (also needed for the cnc). You'll also need the degrees of axial rotation from one turn to the next. All of these things will be hard to make and measure accurately compared to the cnc bender so your process will be important. If you have a care to make good square cuts, you can simply glue them together end to end. Adjustments would be easy, as you can simply cut them back apart, make whatever changes you need and glue them back together. At the end you should have a good fit with an accurate record to give to the bender. You will have to be super careful to be accurate - even a really tiny miss-measurement will throw off the result considerably when made by the bender. The good news is that after the first pipe is bent, it will be pretty easy (though not cheap!) to tweak the program to hone in on perfection. The bender I have seen reproduced unbelievably identical parts so tiny adjustment were very reliable. I think you will find bending the pvc around a form like a can doesn't work like you think it will. Just get a heat gun and make a few tests and you will see you get a fairly floppy rubbery result that you can simply hold in place while it cools and keeps its new shape. I have made very accurate bends simply by laying the heated pipe on top of some layout lines drawn on some plywood. I would definitely try Mr. irk's sand technique to help keep the diameter under control. I obviously have not tried it but I bet it works great.

Will have a play when I get a heat gun. Nothing like getting your hands dirty and playing around a bit to see how it all works.

Have some kids play sand here to fill the tubes with too so good on that one, just need some end caps.

Will update as I go of course

Worst-case couldn't you just do pie cuts and ask him to replicate without the cutting part? ??? https://www.youtube.com/watch?v=lE1-HjBw3Jg

MotorbikeBruno said:

Worst-case couldn't you just do pie cuts and ask him to replicate without the cutting part? ??? https://www.youtube.com/watch?v=lE1-HjBw3Jg

Click to expand...

Pipes can make great bike porn, love it!

I think the PVC bending is the best option as not only is it quick and simple but I can also easily adjust.

The chap that's welding it up does a lot of pie cut exhaust work which looks amazing and ordinarily would be something I would use, but I prefer the rawer industrial look of the full bends in raw stainless.

Quick question. I am looking at batteries of the bike as after I have finished off the pipes I am looking to finish off all the electrics (given I have my electronic ignition sitting here and not installed). Originally I only had my eye on the Ballistic 8 Cell assuming I had built the battery box for its small size, however looking at my data on the computer (I will also measure later) it appears the box will accommodate pretty much all 8 Cell batteries... which is a good thing as I cannot source a Ballistic in Oz.

So options:

1. Use an Antigravity Small Case 8 Cell (seems to be a good option)
2. Look at an SSB Lithium Battery, also has the benefit of being able to use a standard charger, but CCA is lower (plus I also run one in my Enduro bike and its been going fine for ages)

Overall the SSB seems to be a much cheaper option at approx. $180 for the battery and a cheaper charger vs $240 for the Antigravity and a special charger.

I think the SSB has various control circuits built into the battery enabling it to be used with a 'stock' battery charger. I was talking to some reps at the AIM Expo in Orlando a few months ago about batteries catching fire so they showed me some stuff.
As for ground clearance issues, make a large triangle with 50 degree hypotenuse (that's whats required for moto GP)
It's very unlikely you'll get further than45 degrees with street tyres but some are rated to 50 degrees

Is it necessary to have such a simple tube CNC bent? Why not just buy two 15 degree bend and weld them together? If you cut them perpendicular to the tube it's pretty easy to blend out the weld and make it appear as one piece.