Suspension - pivot tube options

[Kobber]

Hi everyone,

How lucky I am to find an empty page in the forum: first post in Suspension!

Anyway, just downloaded two sets of plans: the CycleBully and the Voyageur, both of which call for suspension.

I picked up a nice used mountain bike (http://www.bikeradar.com/gear/category/bikes/mountain/product/rockrider-63-07-20096) with suspension, disk brakes, the works, got it for a song (only had to replace the chain as it had been sitting outside for about a year) and planned on using it as a donor for one of these projects. But the frame is aluminum! :( Duh, had a fridge magnet in my pocket for weeks, but not that day. And it's even written on the frame.

Anyway, here is my question: the pivot tube is the only part of the frame that I need (the rear triangle and suspension would be used as is), but, like the rest of the frame, it is aluminum, therefore useless to me. Are these pivot tubes standard? What are my chances of finding a steel one that will fit the rear triangle? Will the bolt and internal workings fit the rear triangle?

The bike's still in good shape, a bit of superficial rust here and there, so I could get a good price for it if I wanted.

Thanks for any advice. Take it easy everyone.

Kobber

[PeterT]

Kobber,

My friend Lyn & I dissected three suspension bikes recently, and two of the suspension mounts were the same size tubing as the head stem tube, as a bearing cup fitted perfectly into them. When you get your donor bikes, check all the tubing with a bearing race, check all threads, etc, as most of them are the same size threads.

PeterT

[Kobber]

Hi Peter,

Thanks for sharing the results of your dissection. I sort of suspected that there must be corresponding tube sizes across a given type of bicycle, as this would help the manufacturer to cut costs. But you never know ... I guess I'll have to get down to the nitty-gritty myself and see what my junk pile has to offer.

Kobber