Allie's bike is coming along pretty nicely. I just had her give it a test ride and she seemed pretty excited to be able to ride a "Big Kid" bike. There were a couple of changes I had to make to the frame from the original design. When I first put 16" wheels on the bike the pedals were, as I had previously feared, too close to the ground. However when I put the 20" wheels on the frame they were at a perfect height. The pedals were still low enough that I could have a much lower seat than normal but high enough that they allowed for pedaling without any fear of them striking the ground. Unfortunately by using the larger wheel size from the beginning it means there is no opportunity for the bike to grow. Which in hindsight may have been an idea that was not completely feasible in any case. The biggest problem with the 2" larger wheel radius is that it places the seat at 17" above the ground instead of the desired 15". While the seat height is an inch shorter than her current bike (with 12" wheels!), she still has to jump a little on the bike to get on it and start riding. Anyhow, it seems that for anything out of the ordinary there will need to be some form of compromise and in this case a little inconvenience is worth having a bigger bike than what she currently has. Now all that needs to be done is cleaning up the brass, adding the brake mounts and getting it to the powder coater!
With Easter and everything I have been unable to spend that much time at the shop. Fortunately that is something that I was able to remedy this week! With Allie's bike I was able to finally get the seat/chain stays brazed to the frame and now I pretty much only have to work on the fork and the bike will be ready for its test ride. With the design of this bike being so far out of the range of my comfort zone I am really hoping everything works out. As a basis for comparison a "Specialized" sixteen inch kids bike will have almost no bottom bracket drop (the distance the bottom bracket is bellow the axle line) on this frame I dropped it down a whole 50mm to help with the stand over height. Unfortunately if you drop the bottom bracket too low you can have an issue where if the bike is leaned over too far while pedaling then you can have instances where the pedal will strike the ground. Now, this is something that I have taken into account should not be an issue, however it is still something I am worried about.
If you look at the chain/seat stays you will notice that they extend overly long past the seat post. By extending them this long and then making sure the braces are pushed further towards the seat I will then have plenty of room for the larger twenty inch wheel.
I should have the fork pretty much finished tomorrow and hopefully will be able to have Allie test ride the bike before I get it powder coated.
The front triangle is finished on Allie's bike and tomorrow I will be swinging by Shappiro (amazingly cool metal shop) to pick up the steel for the rear triangle. As the rear dropouts are completely custom I am going to have to fabricate them myself which should not be that difficult just a little time consuming to get something that looks decent.
In the pictures I have the seattube almost three times as long as it really needs to be. To get the frame to work with my jig I had to cut it almost eight inches longer than the five inches I needed it to be. When I have finished brazing the frame together I will shorten the seattube to the correct length. I might even cut it a little longer and do a test ride and leave it as long as possible
I just took the new cruiser out for its maiden voyage at Castlewood and I had a blast. I had mentioned previously about some of the changes in geometry from my first 29er and it was great to see that these changes made a HUGE difference in the way the bike handled. Not only did it handle like it was on rails on the downhill but when the bike was pointed uphill it felt much more stable than what I am used to. Also the fork held together on its maiden voyage as well. I can't say I am completely sold on the idea of rigid forks, however on the flat twisty stuff it was pretty nice.