Hi everyone,

This is my very first post so please excuse (if any) my lack of knowledge of both forum rules or anything else. I will try to improve as fast as I can.
I am 54 and got bitten by the N+1 "mosquito" and own now 11 bikes of the most diverse types, makes and ages. I am trying to learn as fast as possible but i's a trial and error process I fully acknowledge.

I bought today a road bike that is equipped essentially with RS100 from Shimano. Unfortunately the frame has been repainted (badly) so I have no idea of the make. Could you please help me a little bit? It has an English BB marked *** 1.37"x24 tpi. The tubes are 28.5 and 25.4mm. Please find below some lug pictures and the serial number.
Any advise will be highly appreciated.

Bump for thread caught in the spam filter.

Welcome, [MENTION=473297]Danj54[/MENTION]! (Will you change that handle next year? )

I don't immediately recognize the details or the serial number, although the seat cluster is reminiscent of what Dawes did. Looks like a lower to mid level bike from the eighties. Perhaps if you were to post a full side shot of the bike, preferably from the drive side, it will trigger some more memories. Is 25.4mm the diameter of the seatpost?

Hi non-fixie,
Here is the side view - unfortunately not the drive one. The seat tube and the down tube are 28.5mm. The top tube is 25.4. Does that help?

That looks like the later serial number format used by Motobecane/MBK.

Thank you T-Mar. Any idea of where I could find that database to search through?

That plastic-cupped SKS bottom bracket was an '80s French bike thing.

Is that another element suggesting a potential 80s MBK?

Yes, but Peugeot also used that part during the same period.

This is the tool for installing and removing that bottom bracket.
FAG2.JPG

FAG1.JPG

Thank you thumpism, I'll keep digging. Is there somewhere a database to try to identify the serial number?

As far as I know, T-Mar is our resident database for frame identification. He and others here have immersed themselves in that knowledge and I defer to them on these matters.

The S/N format is incorrect for Peugeot. While it is consistent with Motobecane/MBK, I have been unable to collected sufficient data to determine the code. I also don't know when they switched to imperial tubing and English threads but most French manufacturers did this sometime in the 1980s. The 25.4mm post suggests an entry level, hi-tensile steel frame. I am surprised to see a recessed bake nut on the rear. There isn't one on the front, so the fork may not be a match.

The rear brake is RX100,which would suggest 1990s. However, the rear derailleur is much newer Shimano105 (5700 series) and the front brake is an older,single pivot model. I don't have lot of confidence in the RX100 being OEM. Bikes at RX100 level typically had better tubesets by this time.

Looks low mid range priced Asian to me - the tell: stamped steel fork crown, swagged seat stay tops and inch sized main tubes.

What's the diameter of the seatpost? That's somewhat of an indicator of the seat tube wall thickness and the quality of the tubing.

Here's a suggestion of the areas of a bike to photograph to get more than guess responses.
Edit: I looked over your photos again and you've already done this.


Chas.

In the first post he says it's a 28.5mm seat tube with a 25.4mm post, indicating imperial tubing and hi-tensile steel. It also had an English threaded BB shell. However, the serial number format is consistent with later Motobecane/MBK. Do you know what year they switched to imperial tubing and English threading?

OK, I didn't get that he meant the seatpost when he said the tube was 25.4 mm diameter. I was actually sort of confused as to what tube he would have been talking about.

@Danj54 wrote "The tubes are 28.5 and 25.4mm." I didn't see any mention of seatpost diameter. 25.4mm seatposts were used on gas pipe French bikes up through the mid 70's (25.0mm, 25.3mm and 25.8mm too).

T-Mar, I don't know that they ever did. All of my French bikes from throughout the 80's have metric tubes (4 Motos, 6 Gitanes, 5 Bertins, 5 Peugeots and 1 Mercier).

Some have British threads and use 22.2mm stems but there's no logical time line as to when the switch from metric threads took place.

My 1986 Bertin has metric Reynolds 531 tubes with French threads and my early 90's Bertin has metric Reynolds 501 tubes with British threads.

I'm in the middle of replacing the headsets on my 1983 Peugeot PSV-10 (metric) and the 90's Bertin (inch) so my measurements are very fresh. Dug through my box of headsets looking for a metric Stronglight A9. Only had British so I got one coming from eBay.

In the late 70's we started seeing Peugeot U-08s with British FWs and pedals, even a few with British BBs, even 1-2 with Swiss BBs coming into our shop for service - we didn't sell em, only worked on em (looking back, they could have been Canadian made or assembled).

I have a 1974 Gitane TdF that came from OZ. It has British threads with metric tubes. Probably made for the Australian market.

Is it wrong... Or just French???

Chas.