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Tandem Design Work-around?

Hi Brent,  

I'm trying to model a mtb tandem, and what I did was create the captain seat tube forward in one model, and the stoker seat tube back in a second one.  I don't need miter templates, but I will need angles and lengths for front and rear of the bike.  Then I'll simply fill in the middle by using whatever length of boom tube I decide on, and then fit the lateral and stoker top tubes as needed.  Since the boom tube is generally level, using the same BB drop in both models would seem to give me a useful model to follow.

Does this make sense, or am I asking for trouble?  For whatever it's worth, this is my first tandem build, and it's really just intended to take my grade school age kids mountain biking with me.  Of course I'd like to aim for accuracy, but in reality, as long as it's safe, it's going to be good enough.  Ending up with the correct head tube angle is probably my main goal. 

Thanks

Tandem Design Work-around

I'm sorry for the delay in creating this oft-requested option.  However, in the meantime, that does seem like a reasonable approach.  Good luck with the project.  It would be cool to see the results posted in the Show and Tell section of the forum.

tandem

Having built a mountain tandem for the first bike I built here are a couple of issues and how I solved them.  Boom tube.  I used a 29er down tube.  seat tube, Use a 28.6 and then use a stem with a seat post shim for the stoker stem.  Or make the front seat post really long.  Then use the stem as the seat collar.  You can then move the stem up or down on the seat tube.  Hope that makes sense.  The problem is the industry uses a very specific seat tube diameter and you can not find a stoker adjustable stem that will fit the tubes that you can buy.  Paragon machine makes a cool head tube but finding someone with a tool to ream it is difficult.  I found a seat tube reamer on line for like $40 bucks new.  do a search for adjustable reamers.  The next problem is that it is difficult to find a rear top tube long enough to match the boom tube.  I found that welding both tubes together in one long tube and then cutting a hole for the seat tube worked for me.  Tons of clearance is cool but you have to make sure that you make sure that you dont make the top tube so high you cant jump off (ask me how I know LOL)  Good luck

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