RB1-luvr

dig it!

BikePower

The truth hurts and as the saying goes, truth is stranger than fiction.

Even though at one point I was convinced that this Ross Paragon is my original bike that I bought when I was 15 and by the miracles of fate it was brought back to me, I came to the irrefutable conclusion today that it is not in fact my bike.

Those dang handlebars kept nagging at me. I asked myself how sure are you? To which I replied, I am pretty sure. I asked myself, if you were on a jury, would you convict or do you have reasonable doubt. I had to admit to myself that I had reasonable doubt and it was the dang handlebars and the bike felt smaller than i remember.

I was able to rationalize that all away and convince myself that I bought the bike earlier than I did, when i was smaller, and people replace bars and stems to find the right fit. The abrasion on the rear derailleur, I remembered it being worse than it is. I rationalized that as time passes we remember things worse than they really were. That it had an abrasion at all was convincing to me.

The location, Janesville Wisconsin, that was the last known location!. and lastly the astonishing Flick Stand that I never saw on any other bike ever. Surely it was reasonable for me to believe it was my bike? Then there was the drawing made by P!N20 extending the top tube to demonstrate that it was likely a 21" frame and not a 23.

I didn't want to question it too much because honestly I wanted to believe it was my bike and I was afraid that I might not buy it and then after its gone find out that it was in fact my bike! I couldnt live with that kind of regret.

I guess I don't regret buying it. After all it is a great story and a great bike. (but too small).

So anyway, here's how I know for 100% certain that I am NOT the father. ermm eh I mean uh that it is NOT my original bike.

Looking at P!N20's drawing today and comparing my 21" bike in front of me to my original bike in the chess photo, I asked myself if it was possible to actually measure the pixels and compare the measurement to a known difference between the 21" and the 23"

I was able to find a 23" Ross Paragon for reference in real life. I measured the distance between the water bottle mounts and I got 64mm on center. I did the same on my 21" Ross Paragon and I got the same number.

Using the measuring tool in GIMP (like photoshop) I then measured the pixels between the water bottle mount bolts on center in my chess picture and I got 90.5pixels. Knowing that this distance was 64mm in real life, I divided 90.5 by 64 and concluded that there are 1.414mm per pixel.

I then measured with a tape measure the distance between the cable guides on the top tube on the physical 23" bike and it was 163.5mm. I did the same for the 21" bike and it was 152.5mm.

When I used the software to measure the distance in pixels between the cable guides in the chess photo, I got a startling reading of 232pixels. 232 / 1.41 = 164mm which is within a half millimeter of my actual measurement with a tape measure on the 23" bike! This proves the bike in the chess photo is a 23" bike and the bike I have now is not the same bike.

Based on this sad data, I concluded that I deceived myself into believing that the 21" Ross Paragon in front of me is my original bike come back to me from 1988, when in fact it is not, and I wept bitterly. (ok not that much).

Chuck M 

Knowing this is not your Ross from back in the day should only have knocked off a bit of the luster. But enjoy it anyway.

BikePower

Im not getting repeatable results with other photos however. I dont get it. What am I doing wrong? Could this still actually be my bike??

icemilkcoffee 

As long as we are looking at gift horses in the mouth: I think the better objects to measure, would be the ratio of the length between cable guides, to the length from cable guide to seat post, and cable guide to top tube decal. The important thing is that you are measuring along the same axis, in close proximity. When you are measuring along different axes the perspective of the camera can and will make that impossible to compare accurately.

Eyes Roll

Your wife is very lucky.

BikePower

Ok I did as you advised using the ratio between the two dimensions on the same axis and I am getting more consistent readings which supports the suspicion that the bike in the chess pic is 23" not 21 like the bike I have. Thank you very much for that insight! I will do further testing with photos. I suppose if the photo was not taken totally perpendicular it would throw off the ratio. In the chess pic I think its not square with the camera. There is no way for me to duplicate the angle or determine what it is in the chess pic.

BikePower

Im still not sure. Im not getting reliable measurements. There just arent enough clearly defined frame landmarks to use on the chess photo. Back at square one.

P!N20

When using Bluebeam calibrating the scale to 64mm (c-c) between the bottle cage mounts, I get 163.01mm (c-c) between top tube cable guides.

BikePower

Heres an actual scan of the slide that I made today. The previous picture was just a phone picture of a projected slide on a wall. Im hoping the extra detail will help me determine if its the same bike or not.

BikePower

That means its a 23" bike. So with bluebeam its possible to calibrate on one axis and measure on another? That would be awesome to know for sure either way, is better than not knowing.

P!N20

Yep. Using the higher res image I get 161.48 c-c between cable guides.

BikePower

Thats still pretty close. Thanks for doing that. I tried downloading Bluebeam but I couldnt get it to work.

Can you see what the distance is between the cable guides on this pic using the waterbottle lugs as calibration. (63mm).

That would be awesome thanks!

Homebrew01

Isn't black in trouble ? Looks like checkmate as the bishop protects the queen.

BikePower

I remember I liked to use the Queen a lot back then. I lost her many times.

P!N20

Cable guides measure 164.91mm c-c

BikePower

This is whats confusing to me. This bike is a 21" bike and when I measure with a ruler , between the cable guides on center, I get 152.5mm. When I check it in GIMP my photoshop software it also tells me that it is about 165mm. Why is this? How can it be right on the money on the Chess picture bike, which we dont know the frame size, but on the 21" bike that we know, we get 10mm error ? Even with advanced software . There must be a way to be sure what size the bike in the Chess pic is. By the way, thanks for your effors I appreciate that.

P!N20

Something's not right. Maybe take a photo against a light coloured wall trying to be as square to the frame as possible. Get down so the lens is roughly between the bottle mounts and cable guides. The photo only needs to include those elements. You could even get back and zoom in as much as your camera allows in order to create as close to a true elevation as possible.

Just so we're on the same page, this is where I'm taking the measurements:

BikePower

yes thats the measuring points Im using also.

BikePower

Does the bike in the chess photo look like its square to the camera? Is that why its right on the money? or, maybe it is not square and it is actually a 21" frame and the numbers are coming back 10mm larger than actual? If I could duplicate the angle somehow. Its hard to see what the angle is that I took the shot so long ago.

P!N20

I guess that's the unknown, but it looks more or less square to the camera, so you'd think it would only affect the measurements by a millimetre or two.