One inch steering tube options

[specbill]

This is my first post… I’ll try to be brief … first I really want to say how great everyone has made this tandem forum. I particularly appreciate the expertise and time given by the regular contributors… you have certainly saved me time, money and needless grief. Thank you!
We have a Cannonade tandem serial #19 17 590 34**. I bought the frame/fork new in late 1990 and had it built up with the good stuff of the day…..XT, Phil Wood etc. Our team is 305 pounds. We now live and ride in a hilly – rough paved road area. The bike was very lightly used until a year ago then ridden a lot since.
We love the bike more than ever because it fits us both well, is bullet proof, very stable on the road and is in like new condition
After much homework, I made the easy decision (at least in my mind), to go the upgrade route to obtain some newer technology instead of buying a whole new tandem. I thought I really had my arms around what I had frame-wise and where I was going with the rebuild. Phase one was a major power train and wheel upgrade which is well underway …..so far I’m spending pretty much what this forum said I would.

Now for the issue…the fork steering tube.
To my dismay and horror, I just now realize the bike has a one inch steering tube. I spent so much time focused on trying to find accurate rake, head tube angle, fork arm length, looking for bottom bracket / crankset replacement options, rear axel spacing gearing options etc, that it never entered my mind that I did not have a 1.125 steering tube….shame on me.

The plan was to do a fork upgrade to carbon, but I assume that is out of the question ..…in fact I am now just totally focused on our safety and wonder just how safe this one inch tube is.

Two Questions: 1. What has anyone’s experience been specifically with Cannondale’s early 90’s one inch steel steering tube’s reliability? Just how worried should I be on bumpy down hills?

2. More importantly, do I have any options for finding a stronger fork…..is there anyway to fit a 1.125 steering tube fork in my frame?
(I’ve read Bill McCready’s recommendation on how to re-enforce the existing fork but I really would like an even better solution.

Thanks.
Bill J.

[TandemGeek]

Two Questions: 1. What has anyone’s experience been specifically with Cannondale’s early 90’s one inch steel steering tube’s reliability? Just how worried should I be on bumpy down hills?

Never seen, heard about, nor read about any Cannondale road tandem having a fork failure due to fatigue. A quick check of the Hobbes forum confirmed that while others have had similar concern... most of it coming about following some dubious marking FUD (fear, uncertainly and doubt) that suggested tandem riders using 1" steerers were at risk. That's not to say that there haven't been 1" fork failures on tandems, it's just that most of them occured on very old tandems that were using single bike forks, e.g., Ron Templin has recounted his '79 Schwinn Paramount fork failure and noted that there were a rash of similar failures on other late '70's Paramount tandems which used single bike forks that may have also had a manufacturing flaw.

2. More importantly, do I have any options for finding a stronger fork…..is there anyway to fit a 1.125 steering tube fork in my frame? (I’ve read Bill McCready’s recommendation on how to re-enforce the existing fork but I really would like an even better solution.

You can't fit a 1.125" steerer in your 1" headtube. Finding a stock tandem fork with a 1" steerer tube these days might be challenge. If you were really concerned about your fork and a periodic visual inspection for signs of fatigue just won't cut it for you, I'd suggest that you contact a tandem frame builder like Dennis Bushnell, Steve Bilenky, Bob Brown, Steve Rex, etc... and see if they would be willing to beef-up the steerer or make you a new fork just to alleviate your concerns about the potential affects of time and use on the original fork.

Hopefully some of the other folks who own or owned pre-93 Cannondales that had 1" steerers will weigh-in with their views. I would note that Cannondale and most other tandem builders who flitered with 1.25" steerers in the Early 90's ultimately settled on 1.125" steerers for their tandems, triplets and perhaps even their quads. In other words, if a 1.125" fork will support well over 450lbs and perhaps as much as 600lbs on multiseat tandems, why would a 1" fork be inadequate for a 300lb team?

Just my .02

[specbill]

TG....thanks for the response, I was particularly interested in your view.. Very helpful and got me thinking more broadly. For now I'll continue diligent maintainance/inspection and enjoy the riding. I've been all over the net looking for specs on this C'dale '90 frame and can't find anything except a few snippets of info in various old posts on this site. While I use the Airfree site to find most bike specs it has nothing for this vintage C'dale Tandem...is there another source out there that I'm missing?

Bill J.

[zonatandem]

Had several tandems in the early days when 1" steerers were the only thing going.
No problems, even with long time use/mileage.
64,000 miles on Reynolds 531 fork on our Assenmacher; did break an 'experimental' fork after 15,000 miles on another tandem and then put 41,000 miles on a non-experimental steel fork; 57,000 on a Co-Motion fork. All steel 1" steerers.
Have seen fork failure on only one other tandem (20+ years ago).
Quit worrying and enjoy riding TWOgether! Just our experience.
Rudy and Kay/zonatandem

[dvs cycles]

The one 1' steerer failure I saw could have prevented had the owner/ rider checked the tube regularly. Tube broke right at the crown and only about 60% was new crack the remaining 40% had rust indicating it had been there for a while. Broken collarbones suck!

[TandemGeek]

I've been all over the net looking for specs on this C'dale '90 frame and can't find anything except a few snippets of info in various old posts on this site. While I use the Airfree site to find most bike specs it has nothing for this vintage C'dale Tandem...is there another source out there that I'm missing?

I'm pretty sure that the 1990 Cannondale road tandem was sold as a frame-only with a chromly tandem-specific fork. So when it comes to specs the only thing you really have are the rear spacing @ 140mm, 1" headtube, and triangular Cannondale Train Station Logo to set it apart from '92 and up models.

As far as checking specs goes "in general" (remembering that you'll SOL on your classic Cannondale), AirFree did some data harvesting when it created the Web site from other sites -- to include some of the errors -- so it would not be my first choice for checking specs. Instead, you're better off using BikePedia's data at this URL: http://www.bike-alog.com/BikePedia/Quickbike/Default.aspx. Epinions and some of the similar product / bicycle review sites also have pretty good specs, to include frame geometry where it's available. None of these are always 100% accurate, but they're pretty good.

[volpi]

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Two Questions: 1. What has anyone’s experience been specifically with Cannondale’s early 90’s one inch steel steering tube’s reliability? Just how worried should I be on bumpy down hills?

I have had a 1990 cannondale road tandem with 1inch steel fork.I have used it for 17 years , not for shopping and not for races : long distance , brevet and touring . Many many km in flat , in mountains,with the sun and with the rain , with front and rear bags or with a trailer . I have changed three couple of wheels , a lot of chains ,freewheels,tires,brakes,chainrings etc. One time i have changed the steer movement. But never i have had problems in the front fork. It had the stock steel fork 1 inch and it was solid as a rock. I have sold it for a new cannondale road tandem 08 but i am sure that the new owner can have again a lot of satisfaction with the bike. And (sic ! ) a piece of my heart has remained inside !
Francesco