Backyard frame building tips
- Thread starter Lowell
- Start date
Malcolm
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Good link Lowell. There are some useful tips there, and it shows just how much you can do yourself with a little inventiveness. The curves he managed with that homemade tube bender are really impressive. Laminating and shaping individual tube formers from oak sounds like a lot of work to me though. I'd be tempted to take the lazy option and borrow or hire a professional tube bender for a day.
You got plans to build a custom frame yourself?
You got plans to build a custom frame yourself?
I test rode a bunch of off the shelf bikes, and for one reason or another they're not perfect for ebike conversions. By the time I made the necessary changes, I may as well start from scratch and have things exactly the way I want.
safe said:Frame Building is Fun.
All you need is a welder and a grinder/cutter tool and you are a frame builder.
Square tubes are the easiest... it's much easier to keep the alignment when the squareness helps the process.
Ugh, no table legs for me, end mill notching only. If you're on a shoestring budget, a hole saw notcher will do an Ok job.
http://www.mittlerbros.com/tube_notcher_holesaw.htm
safe
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Deltabox frame with batteries inside Square Tubes. No need for external battery pack placement worries. Very strong. Current weight will come to about 20 lbs for the frame, but I'm going to drill holes through the tubes top to bottom and that should cut a few pounds. A future frame built of aluminum could be only 10 lbs. I'll be building my own rigid forks and triple clamps using 4130 tube. Each leg of the frame is two 1.25" squares welded together and then ground down to smooth. Thin 0.063" square tubes helps to keep the weight down, but it's still kind of heavy.
The seat will be suspended by a spring... this allows the frame to stay rigid while the seat is soft.
52" wheelbase.
Total battery power will be 40% greater than before. (more if that flaky NiMh company can really provide 14 Ah batteries... which I have serious doubts about)
Deltabox frame with batteries inside Square Tubes. No need for external battery pack placement worries. Very strong. Current weight will come to about 20 lbs for the frame, but I'm going to drill holes through the tubes top to bottom and that should cut a few pounds. A future frame built of aluminum could be only 10 lbs. I'll be building my own rigid forks and triple clamps using 4130 tube. Each leg of the frame is two 1.25" squares welded together and then ground down to smooth. Thin 0.063" square tubes helps to keep the weight down, but it's still kind of heavy.
The seat will be suspended by a spring... this allows the frame to stay rigid while the seat is soft.
52" wheelbase.
Total battery power will be 40% greater than before. (more if that flaky NiMh company can really provide 14 Ah batteries... which I have serious doubts about)
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safe
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Unsuspended weight is evil. But frame flex is also evil.My main goal has been to reduce frontal area as much as possible. With suspension you increase the height of the front end which increases drag. I've found that on my current 140 lb bike that as long as the majority of the weight you have is in the middle things are okay. This new bike will weigh 60 lbs less than the old one, so right off the bat there is less weight overall. The bike should weigh in under 100 lbs and possibly down as low as 80 lbs. Amazing! To be able to go 50 mph on a bike that weighs only 80 lbs will be nice. 8)
In the picture it looks like I will have front suspension, but actually, once completed, it will have a custom rigid front fork instead...
safe
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Lowell said:
I've got some ideas that are difficult to deal with right now.One is that I'm planning to use a dual disk front wheel... I'll have disk brakes on both sides of the wheel and it should mean some serious stopping power.
I want a very rigid front end. If I'm going to use those brakes I need to be sure that the front end doesn't feel mushy.
Also there is an issue with the frame where I need the fork tubes to be pretty wide. The front wheel will use a rear wheel hub, so the width will be wider and I've got clearance issues that need to be respected.
The clip on style handlebars will also attach to triple clamps and so I need to have the tubes rise all the way to the top of the headset.
Add all that together and a custom front fork makes sense. It would be great to have about one inch of good quality travel, but that's currently beyond the scope of this project. (maybe later)
