Folding Bikes - Raleigh Twenty Questions

I recently got a Raleigh Twenty folder that I'm in the process of buying parts for. Before I get in too deep, I have a few questions. First, I realize that the bottom bracket shell is wider than normal. Would it be recommended to cut it down to 73 or 68? Is there any way to cut it down without destroying the 26 tpi threading? Reason i ask is if the shell was narrower I could just reuse the cups and easily source a normal sized spindle. I'm not scared in the slightest to do the work, I just dont see any need to make it harder than it has to be.Second, when dealing with bottom bracket drop, instead of changing to the 451mm wheel size(dont want it as most tires are narrower than I would like and the selection is farely low), could one just buy shorter track cranks in the 160mm size? How much would this even affect pedal strike etc. I'm reusing the Aw hub as they seem to be insanely reliable so I only need one chainring. Third and finally, with the headset, i'm a little shaky with using a wedge with the stock fork. I know you can swap out the top half of the headset and just run a quill stem, but is expanding in something thats designed to be compressed be safe? I'm no science buff and maybe I worry too much but I'm just curious. I've already done searching and just cant get definitive answers to my questions.

With my Twenty, I just ground the sides of the BB with a bench grinder, then used a file to dress them up flat and parallel- I had to take 1.5 mm from each side to make it 73 mm wide. The little chamfer on the edge shows about how much material to take off- it's just about 73 mm when the chamfer is gone.

Then I used a 73 mm wide UN54 BB that I ground all but the outer 3 rows of threads off. When you try to thread a 24 TPI BB into a 26 TPI shell, it will go in about 3 rows, and if you cut 24 TPI threads in a 26 TPI BB shell, you only end up with about 3 good rows of threads anyway. I'd rather modify the cartridge BB, which is expendable, than the BB shell's threads.

I just replaced the whole fork after cutting the headtube down a cm or two. I used this fork, http://www.niagaracycle.com/product_info.php?products_id=10801 which has cantilever brake mounts (the original brakes are anemic at best). Any old 1" threaded headset will do. Then, a quill extender if you want to get the handlebars higher.

160 mm cranks work fine. I have a Sturmey-Archer 8-speed rear hub with a drum brake in back.

Here's a picture:
http://i271.photobucket.com/albums/jj153/Squeazel2/R20-1.jpg

thats exactly the type of answer i was looking for. Did your bike shed any pounds in the process? My idea is basically the same bars just with lighter parts and a brooks. If it would dip into the high twentys I would be content.

Worth checking out raleightwenty.webs.com There are dozens of different solutions to the BB issue.
With regards wheels, the R20 came with either 451 or 406 wheels depending where in the world it was made so swapping from 451's to 406's should be fine.
Quill stems with slotted forks (for the clamp to hold the stem in place) is potentially hazardous as the slot is a weak point that can crack under the stress from the quill.

Worth checking out raleightwenty.webs.com There are dozens of different solutions to the BB issue.
With regards wheels, the R20 came with either 451 or 406 wheels depending where in the world it was made so swapping from 451's to 406's should be fine.
Quill stems with slotted forks (for the clamp to hold the stem in place) is potentially hazardous as the slot is a weak point that can crack under the stress from the quill.

Sometimes the best thing I did for my own Raleigh Twenty was.....leave it pretty much the way it came with limited-and carefully chosen when done-upgrades. That was the best (and most inexpensive) option. Remember that this bike hails from the 1970s and early 1980s. That's part of it's charm. I have heard of people spending thousands of dollars easy on these bikes. In the end, it still is an old bike.

My Raleigh Twenty's own updating, upgrading, and restoration journey: http://sites.google.com/site/compactcycling/the-restoration-of-raleigh-twenty (http://sites.google.com/site/compactcycling/the-restoration-of-raleigh-twenty)

Just finished re-tapping and facing an R0 bb to 73mm to accept a standard cartridge bearing unit... my P20 has seen the same bb modification and it has been rock solid and seen more mods than most 20's on the planet.

Am a moderator at R20web and have posted a how to on a headset upgrade that will retain the adjustable feature while utilizing a real headset which is a very nice bit of work that will not cost a fortune.

If you are going to be running an AW hub there is no reason not to use that pretty Raleigh crank and chain wheel.

Regarding shedding the pounds- Yes, it lost about 3 pounds, but then I added them back by adding steel fenders and that boat-anchor of an 8-speed hub. I built new wheels from alloy rims (a pound), replaced the steel crank with alloy (a pound) and the handlebar/stem/fork lost it about a pound. The tires and tubes are slightly lighter, too.

My P20 started life as a 36 pounds beast and when it was a fixed gear curbed out at 24 - 25 pounds and now that the little fella has a full set of gears must be pushing 28 pounds.

Just scored an 11-34 Shimano 7 speed freewheel (a hens tooth) and am looking forward to installing this as it will give me the ideal range for touring... bottom end has never been an issue but with a freewheel it is hard to find an 11 tooth cog and get the right top end and a 22 - 90 gear inch range.

One day I will build up a cassette wheel so having that 11 is not an issue but like my vintage cartridge bearing hubs a great deal.

Based on Sixty-Fiver's Headset Modification v2 thread here, I went with a Nitto Periscopa quill stem using a Tange G32STR Aheadset, the 26tpi nuts from the original headset, and a Sinz seatpost clamp. Works like a charm. I think the Raleigh fork is more than robust enough to accommodate a quill stem.

On the BB, I went with Phil Wood cups and a Shimano UN72. If I had it to do over again, I might cut the BB shell down to 68 and rethread. That way, you open up the whole world of contemporaneous BBs and cranks.

the Phil Wood Raleigh threaded Stainless cups though expensive at around ~$45 is a quick and simple solution in my opinion[need access to the phil wood tool as well]

for someone with access to a good Park BB facing tool and BB threading tool rethreading is an option. I have access to those tools at my local Bike Collective but I was hesitant as no on there can technically assist me on how to do it right and I didn't want to mess up my Raleigh BB by making a mistake. I also checked the threads on the tool and the the cutting threads didn't feel sharp and probably needs to be sent out back to Park for resharpening. Hopefully one day I'll try it as I have 3 more R20s that are ready for an Alloy crank upgrade.

With access to shop tools, I faced the bb down to 73mm and retapped to standard 26tpi. Used an older Race Face bb we had kicking around the shop--the right side cup does not have a lip, so it is in essence adjustable like the Phil Wood cups. Score!

For the headset, I cut something like 13mm from the top of the headtube per a mod on the R20 forum, used a Ritchey 1" threadless top unit with the original bottom part. In addition to the stock stem clamp, I added another single-bolt clamp under it to keep tension on the headset even when releasing the original QR to take the bars/stem out.

For a stem, I went with the inverted BMX seatpost cut down to length, then a shim and a stem to fit a 1-1/8" steerer.

Raleigh sure is a bother, with their proprietary threading...

Another option on the BB would be to cut it down to 68mm and use one of those new Velo-Orange threadless bb.

I WENT WITH PHIL WOOD CUPS AND A SHIMmano spindle. Local Bike shop made it very affordable. Hard to believe but I think he sold he cups to me for what he paid for them just because the whole idea of the project entertained him.

Velo Orange threadless sounds interesting. That was not an option a few years ago.

I WENT WITH PHIL WOOD CUPS AND A SHIMmano spindle.

what I did on mine is sell the Raleigh cups/bearings/spindle in ebay and it almost paid for what I spent on the Phil Wood rings. check ebay now and these cups sell for around $45 or more enough for a pair of Phil wood rings.

the Raleigh 26tpi cups are hard to find and got quite an interest in ebay the spindle also has some demand not because they wear but they develop pits on the bearing races from people leaving them out in the rain and as water collects inside rust forms and eat it away I had noticed quite a couple of my spindles developing pits on the left hand side where the wear should be on the drive side. I would think the bike was left out in the yard leaning on a wall non drive side with water collecting on the bottom bracket eventually rusting and pitting that part of the spindle.

$45.00 for a Raleigh bottom bracket is nuts... they made millions and if you know where to look can still buy new ones for < $10.00.

$45.00 for a Raleigh bottom bracket is nuts... they made millions and if you know where to look can still buy new ones for < $10.00.

my local bike collective got rid of a pile of cottered spindles mainly raleighs as theres too many of them and no one wants them even if they gave them away it was just taking precious bin space at the shop

the square tapers almost doen'st last long on the bins and end up on kids building fixies

I am pretty sure that the Velo Orange threadless won't fit due to protrusions where the tubes are joined inside the BB. If anyone has done this, let us know.

Am a moderator at R20web and have posted a how to on a headset upgrade that will retain the adjustable feature while utilizing a real headset which is a very nice bit of work that will not cost a fortune.

Link please, I could not find it.

Link please, I could not find it.

BF Version - http://www.bikeforums.net/showthread.php/677212-R20-Headset-Modification-v2.0

Please note... need to re-load images of the finished mod and will do that when I get home.