Originally Posted by
rthomer
Thanks for the reply and link. The fork is 1-1/8" for sure.
My question is : what is correct rake and axle to crown measurement. I got an email back from Scot Nichols, the original owner of Ibis, he has confirmed the rake at 2.2" aka 155mm. He didn't know the correct axle to crown length, but said it wasn't suspension corrected. Santana uses 155mm, but 1-1/4" steerer tube.
Co-motion has available forks with 145mm rake. Not sure how this affects the steering, it does change the trail. I now doubt that I'm going to find an "off the shelf" perfect solution.....some compromise is in order unless I go custom.
It is my opinion that there is not correct rake and height. If you mean the stock fork that came with the IT then I suggest looking in the manuals on the web site. My point is that there is a variety of acceptable trails used on road tandems by major manufacturers. Rather than correct or incorrect it is a matter of personal preference. On a 73 degree head tube 55mm - 45mm rake is common. I have ridden a 62mm rake fork and actually preferred it when using 30mm or wider tires.
The fork height can be important but due to the long wheel base on a tandem it is not as critical as on a single bike.