Re: [CR]Vintage Assenmacher Tandem, questions on parts

(Example: Framebuilding:Paint)

Date: Tue, 27 May 2003 10:14:44 -0400
From: "Mara & Steven Maasland" <TheMaaslands@comcast.net>
Subject: Re: [CR]Vintage Assenmacher Tandem, questions on parts
Cc: classicrendezvous@bikelist.org


Thomas wrote:
> A couple of questions for the group.
>
> The front crank arms are 170's, instead of my prefered 175 mms.
> Does anyone have a set to trade? (Okay, stop laughing now). If
> not, is there a source for the tandem arms? Is it advisable to
> get a set of regular TA 175's and reverse the pedal threads via
> the methods used to repair stipped threads? Would any other crank
> arms fit a BB sized for the TA fronts? Or are TA cranks a poor
> choice these days for tandems, and I should just replace the whole
> shebang? (Harris Cyclery has Sugino Fuse sets advertised for $180
> total, minus bb's.) My concern is the stiffness of the chainrings
> running a Tandem sized outer. The bike currently has 58-52-30
> rings. The prior owner was much manlier than I, or else the
> downhills around Saratoga Springs NY are immense.

I wouldn't change the 170's for anything different until you ride the bicycle. A tandem rides different enough that the ride will likely be far greater than the change in crank length ever will be. I bet that you will become accustomed to it quick enough as is for use on the tandem only. If you need to replace them, you can always get some new tandem ones from Mike Barry at http://www.bikespecialties.com and with TA, you need only change the arms an not the whole shebang. Regarding the chainring sizes, you'll be surprised how commonly used a 58 is. When I was younger I had my racing tandem set up with 46-56-66. I have now dropped it down to 40-50-60 and am thinking of dropping the smallest just a tad more, but will keep the two larger ones as is. I have however set up the drive to the front cranks which allows my 5-cog freewheel to give me 15 usable gears with no lateral flex problems for the chain.
> I'm worried about replacing the 27 inch rims down the road. Does
> anyone have a source for 48 hole 27 inch rims? If I get a spare
> set, I can forget about it for several years. I don't know if the
> frame will take 700c rims, because I can't see any mechanism for
> vertical adjustment in the Mafac cantilevers. I'd like to leave
> the brakes on because they look ultra cool, but if I get stuck in
> the future, will it be possible to replace the Mafacs with more
> modern brakes that will adjust down to hit a 700c rim? Or is
> there some way to adjust the Mafacs vertically?

The Mafac cantilevers can generally be adjusted reasonably well for height by simply moving the unthreaded brake block posts in and out and then adjusting the straddle and brake cable tensions. I have modified a few bikes for use with 700 c rims without any problems.

Steven Maasland
Moorestown, NJ