London Fixed-gear and Single-speed

Just dug out my raleigh pursuit which is an ongoing project that I plan to finally get finished ready for this summer.

Have been mountian biking/jumping for ages but fancy a singlespeed road orientated bike, so a few newbie questions...

1) how do you make sure the chainline is straight? As presumably once the singlespeed freewheel is screwed onto the hub you can't adjust the position...?

2) As this is probably going to be something not much better than a beater will I be able to get away with running cheap single wall mtb wheels? something like this:

http://www.ebay.co.uk/itm/1808165556...ht_3458wt_1344


3) Are there any similarly priced road wheels?


Thanks

1. Bottom bracket length/chainring position on spider/spacers
2. http://www.ebay.co.uk/itm/Raleigh-Tr...item7dbe0e8208

Excellent thanks, pretty sure I need to run 26 inch wheels tho, the frame seems very small for 700c's, shall have a measure up in a minute...

Here's the frame with the maximum wheel radius I can run... Clearance up the seat stays is slightly tighter still, around 340mm maximum.

Is this enough room to run 700c wheels?

Ivegot a Raleigh pursuit, drop 700cs on, loads better. Split down the geared freewheel and space out to correct chain line. Generally about 3/4 out of 5 for the big ring at the front.

The best mod I ever did to mine was fitting a good front brake - besides making it fixed. File out the drive side dropout so you can tension the chain.

Love mine tbh :)

so there's definitely space for 700cs in the frame?

yes

Okay well in that case they may be an addition at a later date if i happen to come across a reasonably priced set, for the time being i've found myself a pair of useable 26" wheels from the back of the shed!

Next question, gearing... In your experience what's a reasonable ballpark gear ratio to run? Obviously taking into account that for the forseeable future i'm going to be on 26's. This doesn't need to be a flying machine, and has to contend with a (semi) hilly commute, as well as my general lack of fitness...

Will be running a 52 tooth sprocket. (not that his has any bearing on the ratio of course)

Thanks again

With 52 front I would go for 18, 19 or 20 rear.

Cheers boss!

I've been using 52-19 on 700c for a short while, i commute and its hilly, its been a great all rounder. I would also like to try and 18t now.

Well I had 52-18 but to me that was a bit to much. So I bought an other chainring and now I'm doing 51-18 which is cool to me.

nutsjesmoar, was that on 700c or 26 inch?

700c

Original(?) "Custom" crankset cleaned up pretty well and shall be re-used :)

Get the grinder out and take that inner ring off!!!!!

I run 52-20, about 70gi, I can get up 16% hills, and I'm not amazing on a bike.

Just check you've got enough width to run 26" wheels, and what you doing about brakes???

I do just have the clearance to run 26's, will probably go 700c when funds for a decent wheelset become available. As a stopgap I've bought some (very) cheap 26 x 1 1/4 tyres which i can run for the time being. So hopefully 18t on the back will work out okay.

Re. Brakes, probably just a front for the time being, I've dug some nice retro looking side pulls out of the parts box, along with some levers, shall post pics at some point.

nice frame

If you're running 26" mtb wheels check the tyre sizes first, that sounds like the old style 26" tyres.

okay, just mocked up the bike with a 26 inch wheel from another bike, frankly it looks daft, going to have to just bite the bullet and go for 700c I think. Not sure I wish to get into the business of trying to mix and match obsolete old british tyre sizes with wheels that probably aren't available anymore, I can just see it being a can of worms which i'd rather not open!

Does anybody know off the top of their head roughly what the total diameter of a typical 700c wheel+tyre is? Just so i can be sure they'll fit the frame before i spend money...

http://cgi.ebay.co.uk/ws/eBayISAPI.d...#ht_591wt_1110

Any idea why the description here specifically says these are unsuitably for singlespeed freewheels?

http://passionford.com/forum/restora...peed-bike.html

Thats the start of my build, took pictures but never got round to updating it :(

What size is your frame? And what size wheels are you running?

you can just see the label on the tires, its 700c.
not too sure on the question re unsuitable for single speed freewheels, different threading maybe?

I'd have thought your frame is fine with 700c wheels, but you may need long drop brakes if it was designed for 27" wheels. I'll measure both my sets including wheels so you can judge for yourself.

I've got an rc brake of a bianchi, tis fine, the original also worked fine. Frames a 59, 5cm to big, but I didn't know about road bike fitment back then

dishing of the wheel for gears would mean the chain line would be out with a single speed freewheel on it. Not a massive issue, as you can run a wonky chain line, but it'd be much better to get a suitable wheelset.

presumably i could get the wheel re-dished then? Just found an old 700c wheel which i didnt think I had, it's a front unfortunately, so not much good for sizing the frame, but i held it roughly in position and i'm now fairly confident there's enough room. Fits in the forks with a nice tight clearance at the top, about 4 mm ;)

New bottom bracket arrived today, which fitted nicely, but for the fact that the threads inside the frame seem to have come close to being non existant, so no real idea how long they'll last before they rip out and i'm looking for a new frame :(

On the plus side the silver cranks look pretty neat against the black frame. Pictures in a minute!

+1
Though inner ring on that might unbolt.
Its not going to be the stiffest crankset, but you could do worse.
27" = 630mm
700c (known as 28" or 29" even though its nothing like) = 622mm
650c (26") = 612mm (?)

Mine weren't bolts, and grindy grindy is loads more fun ;)

Mine skids fine, with a seriously shite chain line - 130mm hub, pull the frame apart to get it in cos there 126 spacing with a cog screwed onto the freewheel threads

Would it be possible to put a 120mm hub on and just squeeze the frame as you tighten the hub up?

I have the same cranks and i am planning on using them for my fixed until i get some sugino 75s. I used a drill on the back of the rivets to remove the granny ring, looks much nicer.

Well i'm tempted to leave it for a little additional stiffness. Settled on 700c now, the clearances look like they'll be pretty awesome! Debating purchasing a set of halo twin rail couriers for the tyres, anyone have any experience of them? Good? Bad?

And what is the original spacing for the rear dropouts? I have no idea whether or not mine has been stretched out or squashed in at any point in its life...

Raleighracer, can't you adjust the spacers in your hub to get the correct chainline/width?

Forks back to bare metal, thinking clear lacquer...


http://i49.servimg.com/u/f49/15/09/68/70/p1070517.jpg

http://i49.servimg.com/u/f49/15/09/68/70/p1070518.jpg

Rear spacing is 126mm,

And possibly, but then I'd need to re-dish the wheel :/

Just been offered a wheelset for £50, my only concern is that the rear hub is flip flop, how does one adjust chainline when you wish to use cogs on both sides of the hub? As it obviously rules out re-spacing the hub and re-dishing the wheel, as by making one side correct in this manner the oher side would surely be thrown even further out of alignment?

no. flip flop hub is what you want for singlespeed. they are centered between the drop outs. a wheel for a screw on cassette will be dished towards the non drive side of the wheel to accommodate the size of a screw on freewheel.

Does this mean the chainline is guarunteed to be correct?

Wheelset i've been offered is on the red frame. Brand is Nologo... Any good?

No chain line won't be right with a single speed wheelset

no, it doesn't mean its guarenteed to be correct, that will be down to your bottom bracket length and crank type. However, if you get a rear wheel that is dished for a screw on gear block then the chain line is guaranteed to be off. So, buy a rear wheel that is designed to be used with a singlespeed freewheel and the cranks you already have and you should be fine. Perfect chainline is not a necessity as already discussed, though it's nice when you can get it.

That wheelset you've been offered: find out if it's sealed or loose ball bearing hubs, sealed is better. I assume they're these £100 new so don't pay more than about £50-£60 pending condition. As long as they run smooth they should be fine until you can afford something better. If you can wait, keep your eye on classifieds.

Good to see another Pursuit. Do you know what year it is? Have you owned it from new?

I'm guessing 700's are fine on these, right? I only have a basic understanding of older bikes, and i wanted Fulcrum Racing 7's on it.

Fred, those are indeed the ones, just picked them up, paid £50, they run true and free so i'm reasonably happy, and just judging by eye the chainline also looks very close to being spot on.

Tommy, I haven't owned it from new, it was given to me in a poor state, I haven't a clue what year, but the serial number is still readable if it would mean anything to you?

Shall post pictures in a minute :)

Yeah, had to do a lot of research on mine, got mine down to the month and year, and which factory it was made in. Weird thing with it though, i've never known the serial number to be at the top of the seat post tube, only under the BB.

Post me a number, and i'l drop the links in, and info :)

8113091, found at the bottom of the seat post tube, just above the bb

Was there not 2 letters at the beginning of that number series?

Here is the list of serial numbers needed to work it out.

I also have 63119 under the bb, but no letters in evidence anywhere...

Hmm that's really weird. You're UK, right?

Mine starts with NP (Nottingham factory, November), then 6 digits.

I am indeed in the uk, though i suspect mine may be significantly younger than a lot of pursuits, i'll post some pictues of it in it's original guise later if that'd be any help with dating...