Originally Posted by
uspspro
My purpose for comparison isn't to say that they will feel all that similar, but more so to say that switching to a 45mm rake fork with a similar A-to-C length will not make the specs fall outside of generally accepted values.
In that regard, then yes... at least to open-minded frame designers you're still in the box but tucked into the 'performance' corner of that box.
Originally Posted by
uspspro
Logic would lead me to assume those with the Alpha Q forks have a longer head tube at the bottom to compensate for their shorter forks.
It depends on whether or not a frame was designed around the Alpha Q fork and who did the design. Like a lot of early converts to the Alpha Q, we just sucked it up and dealt with the lowered headtube / altered geometry of the entire frame. That meant changing saddle positions, tweaking the stem and learning to cope with a little less crank clearance on corners for our '98 Erickson. Our '02 Erickson was designed around the Alpha Q; however, instead of making the head tube longer Glenn elected to lower the entire frame, to include giving it lower front & back bottom bracket heights. Invariably, I'd always clip Debbie's pedal within the first 3 miles every time we moved back to our '02 Erickson from the '98 because of this subtle difference.
Our Calfee is definitely designed around the Alpha Q and I confirmed with the folks at Co-Motion that they design their Supremo, Robusta and other 'race' tandems around the Alpha Q forks, whereas the Speedster, Roadster, etc... are designed around their chromoly & the Wound-Up carbon forks. As to what aspect of the frame is altered, it would appear to be dimensions about the head tube as the bottom bracket heights are standardized across their entire road bike range.
Originally Posted by
uspspro
I seem to remember TandemRacer fitted a HT spacer at the bottom when he ran the Alpha on their Lightspeed.
Actually, TandemRacer rode their Litespeed without the spacer for the vast majority of the time they had that fork on the bike. It was shortly before their AME-built Alpha Q fork started to develop cracks (about 20k very hard miles or so?) that a friend up in Asheville, NC, machined a custom spacer for their tandem and Alpha Q fork. Once he realized the Alpha Q had reached the end of its service life TR contacted the new owners of the Alpha Q, True Temper, with regard to a replacement. While they had a great replacement program / price, they didn't have any tandem forks of the correct spec in stock at the time so they ended up switching over to a Wound-Up fork which, I believe, TR found to be much more to his liking anyway.