koniczech

Hey everyone,
First time posting here, and thanks to everyone for helpful information while I was reading under the radar.

As an introduction, I have been riding my Schwinn Le Tour for the past 3 years and have decided to try building up a single speed piece by piece. The frame that I found for cheap on craigslist turned out to be a Ross (I'm thinking Gran Tour II due to the 'safety fork tips' and lack of frame shifters, maybe '82) which I thought was a bit quirky at first, but it's my size and I like steel. After sizing it up with a ruler -and not a caliper- I settled to buy some parts online to adapt the stem, and a seatpost. I had already found a cheap 31.8 handlebar, so my backwards workflow was to adapt the frame to fit the 31.8...

My frustration currently comes from the final realization that the stem is 21.15 mm and seatpost as 25.0 (or smaller.) I had thought that 22.2 stem (to adapt up to 28.6 for a 'threadless stem') and a 25.4 seatpost were relatively standard and probably the smallest I could go for my goal of modernizing this bike.

TL;DR: Dimensions on my Ross frame keep turning out to be not-so-standard.

Am I going about this the completely wrong way?
Do I need to settle for a shiny 21.15 quill stem and toss the hopes of using a 31.8 handlebar?
Is the Ross frame worth all this?
Should I be afraid of future 21.15 stems?

Thanks in advance for any tips!

Lascauxcaveman 

Welcome to the forums.

The stem and seat post on my Ross Super Grand Tour Professional that I converted to a fixie were both odd sizes as well. Fortunately, I read some old threads here which pointed out those oddball measurements and so I kept it all together, except the wheelset and crank.

Hopefully you didn't pay too much for that frame, it's not a very good one if my experience is any indication. Heavy 1020 tubing and stiff and punishing ride. You can probably find the odd size seatpost online, but I don't know if it'll be worth the effort and expense. A stem that will fit your steerer tube AND a 31.8 bar? I dunno. I doubt it exists.

Insidious C. 

All 21.15 stems are made for 25.4 bar clamp diameter AFAIK. Also the selection of 21.15 stems is poor and they will all be lower quality. 21.15 was standard for cheaper bikes that typically also came with one-piece cranks "OPC". I suggest getting a different frame. Or, I hate to suggest it, you could swap the fork. The steerer tube O.D. on your Ross will be 1" same as forks that accept 22.2 stems. But the steerer tube length has to match, and you will need to cobble together a headset since bikes with 21.15 stems seem to also have larger diameter head tubes. Basically it's not worth the trouble.

seedsbelize 

I have the same issue with my 84 Letour Luxe. I didn't find this out until I already had S and S couplers on it, and wanted to be able to pop the bars off without the stem. So it goes. Such a fun hobby.

icepick_trotsky 

I vote dump it. You should be able to easily find something nicer that's more worth the effort.

cbutler

Terminate with extreme prejudice.

Kobe 

I usually have a boat load more into a bike before I realize it may not be worth it. Here you are at one post and you already came to the correct conclusion.

And they say Mothers always drown the dumb ones.

3speedslow

And they say Mothers always drown the dumb ones.[/QUOTE]

I can tell you a country boy ! City folk let'em play in traffic !

Koniczech, welcome to the Forum. Sorry to hear of your predicament . It's happened to a few of us. Not so bad when you gather enough parts in the bins to solve the unexpected problems that sometime come up.

With this frame, it is time to decide yourself what you want to do and act accordingly. Let us know how it turns out.

PS... I vote new frame, standard parts so you may upgrade your ride when better frame shows up.

mstateglfr 

New Silver 21 1mm 0 83" Aluminum Threadless Quill Stem Adaptor Bike Bicycle | eBay threadless adapter to fit 21.1 steerer. You could still have those large bars you want this way. I feel your pain- I have a 25" 1980 Schwinn Voyageur 11.8 which uses the same absurd stem sizing. Another option would be this- its available on Amazon or at Harris as well as other online retailers- https://harriscyclery.net/product/sun...bikes-2534.htm

old's'cool

FWIW, I've had no such issues with my mid 80s Ross Gran Tour.

koniczech

Thanks for the feedback everyone! I'm in line to pick up seven frames this weekend... hopefully one of them accepts somewhat standard sized components. Since this is a first build, I really want to get my hands dirty in order to learn, and not necessarily build my best work ever. Its amazing how much you learn right off the bat, as compared to just riding around and paying people to fix your ride.

Regarding the 21.15 to 31.8 conversion, I asked Kraynick about this last week in Pittsburgh and he had no tips on how to achieve this. I think this means its dead in the water.

... anyone looking to build a Ross?

koniczech

Thanks for the tip mstate. I ended up buying this stem adapter in black to match the stem & handlebars I had bought when I thought the stem was 1". So far, everything is moving forward.

- Stem adapter from 21.1 worked to fit up to my 31.8 hbars, although the slim stem looks a little awkward as it steps up to 1 1/8"
- Seatpost was challenge #2 ; I think it's a 24.2 or some narrower-than-modern dimension, so I bought a 7/8" bmx and shimmed the hell out of it. My only concern now is that I've never used a seat clamp adapter to receive the saddle rails. How do these stay put? It seems like crushing down on the bolts will hold it in place... until i hit a good pothole or if someone really wants my saddle. (this is what I got from amazon.)
- Cheap single-ring campy chorus is going on next once I size the BB!

I'll try to post photos once it's worth looking at. This will definitely be a frankenbike.

mstateglfr 

Good to hear the stem issue seems to have been resolved.

A suggestion on the seatpost- go to a hardware store and buy a digital caliper. Use it to measure the inside of the seatpost.
Seatposts come in .2mm increments. If the tube measures different sizes, go with the larger size. It won't fit right now, but will once to gently hinge the seatpost open to its proper size. A Flathead screwdriver as a lever in the open seam of the tube will open it up to the proper size. Wedge then measure. Repeat until it's open evenly around.

Then go buy an origin8 or whatever other aluminum seatpost you want that is a 'laprade' model. It'll be $15-20 new and probably $7 or so at a Co-OP.
Laprade seatposts are easy to adjust.

That clamp you bought is something I actually change out when I can on bikes I refurbish to sell or donate. It's heavy, difficult to adjust, and just not as clean looking.