Ibis Cousin It Fork
I'm new to the forum and tandem riding, just purchased a 95 or so Ibis Cousin It. The price was decent, and I have a enough spare parts to do some upgrades to make it worthwhile (I hope). My one dilema is that it came with a suspension fork that I want to get rid of. I am having an impossible time trying to find the correct specs of the original fork. I can't imagine that one size fits all, maybe someone on the forum has been thru this.
I'd pay to have one custom made if I can determine the right axle to crown and rake dimensions. Or am I over thinking this and there is a good substitution?
Thanks in advance.
Lots of information on Ibis tandems at this site:
Standard tandem head tube diameters are 1 1/8 inches and 1 1/4 inches. The manual for the IT that I found on the site mentions a 1" steerer. If your bike has a 1" steerer it will make getting a replacement fork more of a problem. Your bike may be different. If all else fails you can remove the old fork and measure the steerer tube on the fork. Santana sold tandems with 1" forks many years ago and might be worth calling to see if they can help you with a replacement. Both 1 1/8 and 1 1/4 forks are available.
Precision Tandems is another possible place for help:
You should also consider the height of the fork from the drop out to the headset race. Since you have a suspension fork that would be the normally compressed height. A change in fork height will change the bike's geometry. This change could be for the better or worse depending on the bike the fork and what you like in a tandem.
That tandem looks like a pretty stiff frame. Once again could be good or not depending on your taste. Good luck.
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.
Originally Posted by rthomer
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.