JTH's HD 883 Dual Sport'ster conversion

That looks like a fun project -- a perfect fit for it's own thread in "Some Assembly Required". There are a lot of very helpful people that pay attention to that thread.

To answer your question, there is an engineering saying "if it's stiff enough, it's strong enough." Which basically means that if you affix everything and you load it cyclically and nothing flexes, it's probably strong enough.

You want to pay close attention to how thick those stamped sheet frame members are: if you load in the middle of a piece of flat sheet, it will flex and crack. Adding a sheet doubler and/or gussets will help prevent that.

My recommendation is to buy the Carroll Smith book, "Engineer To Win". It was written in the '60s, and he speaks very plainly (i.e. not a bunch of math) about good design principles for chassis building. Worth every penny.

This has to be one of the coolest things I've ever seen! EXCELLENT work! I've been riding a Sportster 1200 for many years and I really like the bike, but I've more recently been looking into more of a dual sport/a bike to take long ADV-type trips on. You just turned "my" bike into "that" bike! Just craziness.

Hi Dhito - Thanks and yours sounds like a fun project! Roadracer-Al has some good input already but you might also look up www.tonyfoale.com. He's got some good info on frame geometry and even frame stiffening principals and techniques.

Maybe sketch up the frame/pannier idea you're thinking of and post it in a thread and we can all provide some input and help if we can. Seeing a picture of what you are thinking would help.

That's cool Nick! That's why I built this bike. I've been riding dual sports for a while now and also Harleys, so I just wanted to combine the two. I talked about doing it for years and all my friends probably thought I was crazy. Now that its done, they think its cool, but probably still think im crazy

You are not crazy JTH....and I can speak from experience on what "crazy" is....I have the perscriptions {yes plural } to back that up.

Thx a lot bro, i dont mind some math myself im studying industrial engineering right now.
The only problem is, according to math, lots of small support is better than one bg frame, but as u know, in dual sports that much of welding is real PITA when failing

Oh btw i'll start the thread after my dual sport fairing is done
Its using a pair of projectors powered by h4 35 watt xenon, quite sure it will help me a lot when riding night

Ok thx a lot JTH, sorry for hijacking your thread
I'll look into the link

And maybe i,ll try sketching in google skecthup.. since lots of people mistaken my sketch as doctor's note

Just brought the bike back from BTR Moto where the exhaust was being fabricated. Curt Winter, who made the exhaust, is the owner of BTR and knows what he's doing when it comes to big v-twins.

The exhaust is a sst welded 2-into-1 low pipe that snugs the motor and lower frame rail. When I saw the finished pipe on the bike - I was blown away! He tucked the pipes in tight so they're not vulnerable to a low side drop or big rocks, etc... and the front pipe sits nicely behind the skid plate.

As for the sound - Its actually quieter than the Supertrapp, and has a lower bass'ey growl to it. The Leo Vince muffler has the quiet insert with spark arrestor installed which helps with the needed back-pressure to produce good torque.

The motor seems more snappy and responsive which may be due to the 2-into-1 scavenging benefit. More testing tomorrow to go thru all the gears at speed.

Check out Curt's website for more info:
http://www.btrmoto.com/index.html

The pipe will be part of the new SC3 Adventure conversions and also we plan to offer them as part of the kits/components we will sell.

Here's a few pics...

Absolutely perfect looking on that bike. I love it.

Nice looking bike. Could you put the photos the right way up next time .

I took the SC3 Adv for a test ride in the hills today up to Alice's on Skyline. The pipe works! Significantly more low end torque and top end pull. The 2-into-1 scavenging makes a difference.

I haven't weighed the difference between this pipe and the Supertrapp yet, but I would guess'timate its somewhere between 5 to 10 lbs less. That would put this bike at 465-470 lbs now. I'll follow up with an actual measurement on the scales.

I'm very happy with it...

Are they sideways? The look straight up on my computer.

For some reason they are upside down. -David

Ok here. Might I suggest you turn your IPad 180 degrees (Sorry, I just had to)

lol, I would, but the pics are upside down compared to the text. It offends my OCD.

David

Is there any way to lock it?

The pics are the right way up and looking mighty fine to me

Same on my iPad The test is the right way but the photos are up side down

iPhone shows the upside down put my PC shows the correctly.

Maybe apple are offended by dirt Harley's

The photos at the start of this thread were the same way as the text but the last lot were up,side down

Here's a test picture - let me know if this fixes the problem. I think its a setting on my Blackberry that I set a while ago for holding the phone in landscape angle, but now I cant figure out how to change it back