Utility Cycling - good low-BB base bike for an xtracycle?

Can anyone recommend older rigid MTBs with a low BB for my xtracycle?

The Marin MTB I'm using now has very little BB drop, which would be great for clearing stumps, but I'd rather have something more stable for a cargo bike.

I could not recommend an old one, personally, as most well designed MTB's should have had good BB clearance. However, as a general solution, people have purchased 29'er MTB's and then put 26" wheels on them to get both the frame design and ground clearance they desire.

Here's a link to one by Clever Cycles, a Surly Karate Monkey done in 26" fashion:

http://clevercycles.com/?p=136

That's a smart idea, although a disc 29er is decidedly out-of-budget from this project. Will keep it in mind for the future, though.

Bridgestone MTBs had fairly low BB height, if you can find one and the owner is willing to part with it.

:)ensen.

avocado: Have you considered crank forward? See the RANS Hammer Truck.

GeorgePaul: Thanks, I'll keep those in mind in the future, but they're way over budget for this project.

purplepeople: Thanks! That exactly what I'm looking for. I'll check those out.

With a lower bb you will increase the risk of pedal strike... my diy long-bike has a lower bb height because of how I set up the extension and because I wanted some slightly slacker angles and a wider range of adjust ability for different riders.

I do not find the lower clearance to be an issue but then, I ride a fixed gear folder with clearance and have never struck a pedal either.