First attempt at a single/fixie conversion

52x17 is 80.5GI: a bit tall except for cafe-bantz willy-waving, especially if you're new to riding fixed and/or riding in traffic.

Stronglight bolts are decent and about £7 a set.

No, removing one ring won't affect the chainline of the other.

So I've fitted the cranks back on and measured the chainline of the two rings to be about 43mm. From an eye inspection, the inner 42t chain ring lines up perfectly with the rear sprocket and has the same chainline as it (42±0.5mm).

Am I right in thinking I can just remove the inner chain ring and put replace with the outer 52t one? I'll pick up some bolts and a 1/8 chain today.

Sounds about right: [43.5mm] "Shimano spec, measured to the midpoint between the rings.
with typical 5 mm chainring spacing, this puts the inner at 41 mm, the outer at 46 mm.".

1mm difference in the chainline won't cause any problems, so yes you can just move the outer ring to the inner position.

Awesome. I'll go grab the parts now and hopefully will have it rideable to test by the evening. I'll need to add brake levers though as I'm still sourcing a set. Evans were kind enough to give me (for free) two brake cables and enough cable housing to do the whole bike!

Brakes and mudguards are now re-installed. I managed to get some levers, with good condition hoods for a fiver; the cables and outer housing was free from Evans Cycles(!) and blocks from Sea Bass Cycles in Peckham. They are sharp and the pads aren't even 'worn' into the rims yet. I expect to be adjusting them for a bit as all the parts settle in.

Once the chain ring bolts are here I'll put the 52t chain ring on with the 17t sprocket. Definitely way to high so may source an 18/19t freewheel.

That's coming together nicely: good work!

Bit of a disaster/setback tonight. Chain ring bolts arrived and I fitted them; mounted the cranks only to find out that the clearance for the chain ring is about 7mm, leaving it a very close call. I'm not sure if I have them on enough either as I didn't want to over tighten them...

I thought about buying a chain anyway to see if that's enough etc, so went to fit the pedals. Turns out the fella who sold me the cranks forgot to tell me the non-drive side threads are fecked and wont receive a pedal. So back to square one!

That sucks, but I did warn you.

I'm sure you know this, but the NDS pedal has a left-hand thread.

Indeed you did. If the pedal threads in the cranks were OK I suspect that I would have enough clearance upon fitting a smaller chainring. I planned to do that, but now will just source a different crank altogether. Do you have any suggestions of companies/brands that would be ok? There seems to be so many different BCD standards I don't know which one to pick!

Don't know how much shops charge but you can have the cranks rethreaded some do it to french cranks so as to take English threads, your bike is looking good added pic of my BSA cheap as chips but I love it..

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That looks great, what gear ratio are you running? I was thinking about buying some taps; dusting off my A-level engineering knowledge and having a go at re-threading them. I do wonder if just trying to source some second-hand cranks may be cheaper/easier though.

The Andel cranks from Cyclebasket will suit that.

https://www.cyclebasket.com/m9b0s336p0/Components_/Chainsets_-_Track_1_8_inch_

You'll need a 110mm Shimano bottom bracket with those for correct chainline.

Have a look in the eBay shops for more budget stuff.

Second vote for attempt a rethreading. Nip it to a good bike shop that is local to you and see what they can do - that would seem to fit best with the philosophy of your build so far. Alternatively source a different non-drive side crank arm from ebay and delight in a unique pedalling style!

I do like the idea of this as it's straight 'off the shelf'. Will chat to bike shop about re-threading first I think.

Will look into it and report back! As I need a new chain ring to compensate for the lack of clearance, and the 122BCD rings are a nightmare to find, it may end up more economic to replace the cranks. Hoping for the latter though.

I once did a SSP conversion with original cranks...had to go with a 52T chainring on the front because that was the only chainring with the proper BCD...looked crap.

I then changed the BB for proper chainline, cranks and 46/16T ratio which is IMO perfect for city use.

There seems to be so many different BCD standards I don't know which one to pick!

144mm is the track standard, but that means 3/32" rings are less common (although you can run mixed 3/32" and 1/8" sprockets using a 1/8" chain).

135mm is the Campag road double standard, so suitable (long teeth, no ramps or pins) rings between 42 and 52 are less common.

130mm is the Shimano road double standard, so... [see Campag].

110mm is the compact road double standard for both Shimano and Campag (but Campag have the hidden bolt offset so aren't compatible with Shimano), so suitable rings between 34 and 50 are less common.

And plenty of others which are either obsolete, obscure or both.

:)

That being said, suitable rings in all BCD do exist so nothing is impossible... for a price.

Shimano 130mm BCD are by far the most common, so older road cranks are cheap and suitable rings easier to find.

But you have cranks, Hilary Stone has rings and tapping a thread is easy to do at home/cheap to get done assuming there is enough material left in the eye.

Apologies for repeating something you surely know, but you didn't reply when I mentioned it before: the NDS pedal screws in anti-clockwise. The thread is definitely FUBAR?

I think my gear ratio is 44:17 maybe 16 have changed the rear few times , sourcing another crank could be cheaper but the tools for pedal taps do go fairly cheap plus it's not too difficult as the holes are already drilled and you'll have the tools for other builds (there will be more believe me) I would certainly check what SS said about the left hand thread it's an easy mistake to make,

Excellent, thanks for the information about the different cranks! I appreciate that.

Ah yes I forgot to tell you, I checked the left/right handedness of the threads when trying to fit the pedals. What I did remember is that these cranks are rebranded as Peugeot, so could have french threads? If not then the only other thing could be knackered threads; I'll source some pedal taps and try it that way.

@littleK see above!

From what you wrote, I thought you had got the DS pedal on. If not then having French threads seems more likely than both being shagged. French threads aren't that common here and Peugeot were using British threads even before they completely switched over.

Ah sorry no, it wouldn't go on. Visible inspection of the threads show them being very worse for wear, the first three or four are completely worn away/flattened. I suspect someone has tried to force some regular pedals on it before.

Then you've nothing to lose by having a crack yourself: 180 forward, 90 back and repeat.

Probably best to do that first, before buying a ring. ;)

Been a while since I had a chance to post anything. I didn't manage to retap the threads on the cranks and will keep them spare for another build. Managed to find some good condition second hand Miche cranks with 48t 1/8" chainring with sealed BB for cheap. Went to fit only to see a rivet in the bottom of the BB shell which attached the wire guides for the old gear system. BB wouldn't fit, so had to drill it out and remove it. BB is now in and cranks fitted, chainline is OK too (±1mm I think).

Got a chain and remembered I have some spare SPD pedals so slung them on. Just needs some bar tape (colour suggestions appreciated as long as it's not white!) and final tweaks on the brakes, mudguards, levers/bars position and possibly chain tension and it'll be done.

Edit: so since having a go I think I will be getting a freewheel too as I am not sure or confident about fixed! Also I need a longer seat post (27.2 x 175 mm end to end currently fitted). It's making some weird noises when pedalling and definitely sounds like the chainline isn't ok!

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looks nice. Really like the yellow spds on this too

Thanks! They were just what I had lying about and worked out well!