How I Modified My Raleigh Twenty & What Went Wrong
HTML-код
- Опубликовано: 1 апр 2023
- Ever had an old Raleigh with a wide (77mm) shell and weird threading? In this video I'll show you how to fix that and also what can go wrong.
-- BIKE SPECS DOWN HERE! --
Facebook: /
Instagram: m0nkeyshred
Music: www.epidemicsound.com/
Camera Gear
GoPro Hero 8 Black : amzn.to/33JFH1l
GoPro Session 5 : amzn.to/2KRFj78
DJI Spark : amzn.to/2zS09kO
DJI Mini : amzn.to/2VJO0py
Nikon 18-105mm Lens : amzn.to/3f7f7nb
Nikon D3200 : amzn.to/35tTBV5
Bike Spec & Product Links
1980 BSA (Raleigh) Twenty
Cyclus 24tpi Bottom Bracket Tap : www.merlincycles.com/cyclus-b...
Park Tool Bottom Bracket Facing Tool : amzn.to/3MbOgcE
Ryobi Grinder : amzn.to/3JUJnBS
Digital Calipers : amzn.to/40RfuJp
Fork Cutting Guide : amzn.to/40ABIzE
Bicycle Fork 24tpi Die :
Like the video? Don't forget to give it a thumbs up and subscribe for more!
Didn’t like the video? Leave a comment with what you didn’t like. 
Развлечения
I've done these conversions very successfully many times. I currently have half a dozen high-performance Twentys, each running a converted BB and headset. These have covered thousands of miles with no issues. With the BB, if you narrow to 68mm, rather than 73, you end up with a good portion of newly cut thread on the insides of the original (overcut) threads, towards the centre of the shell. With overcutting from 26 to 24 t.p.i. you actually lose two complete threads around 10mm in on the 14mm of thread each side due to pitch clash. The extra new thread when going to 68mm means there's no problem at all in use; resulting threads are really good, and absolutely perfect at each end of the 14mm depth run. When narrowing to 68 rather than 73, you're taking off enough each side to be able to use a narrow cutting disc on the grinder, cutting a "ring" of BB shell material off, measuring about 3mm each side. This is much quicker and more accurate than grinding and filing. The rest is done with the facing tool. With the headset, I fit a new A-Headset and retain the original stem clamping arrangement using the "T-slot" in the fork steerer but with a replacement external clamp. The head tube has to be shortened by about 20mm (and re-faced of course) in order to accommodate the additional stack height of an A-Headset in comparison to the shallower "hybrid nylon-bush" arrangement originally fitted. The original headset top nut is used to provide pre-load adjustment to the A-Headset. A couple of 5mm 1" A-head spacers will need to be added to the stack. In place of the original chromed steel QR stem clamp, I use an old-school 1" BMX seat clamp. It's important to vertically align the clamp to the steerer's T-slot, but this is easy as you have the aforementioned spacers to juggle with. It ends up as a very neat conversion, looking as if done that way from new and working perfectly. I use Madison M:Part headsets (cheap and very good quality) as they include the unusual 27mm size crown race (26.4mm is industry standard) to fit the Raleigh fork without filing. For a stem quill tube I use an old-school 22.2mm steel BMX seat post with a regular A-Head stem clamped on top. I turn up a simple ally adaptor in my lathe so that a standard 1 1/8" A-Head stem fits on the 7/8" tube. An odd piece of scrap 1" steerer tube in conjunction with a readily available 1" to 1 1/8" stem shim can also be used if you don't have access to a lathe. One of the best additional Twenty mods is to reduce the fork offset by 15-20 mm. Basic cold-setting with careful measuring acheives this. I use a vice and blocks of wood, then measure, using a calibrated set-square, with the fork lying on a flat surface. You're just reducing the curve on the blades a bit - simple! What I often find when doing this is that the original alignment is way, way out, so as well as a mod this is a repair to rectify shoddy original manufacturing! Reducing the offset increases trail and massively improves handling. A stock Twenty cannot be ridden no handed (I challenge anyone!) at all. One with a headset conversion and 20mm fork offset reduction can confidently be ridden no-handed at any speed - from walking pace to 30MPH+. The effect is genuinely transformative. Fitting BMX sized (ETRTO 406) wheels to a Twenty will leave the BB height significantly lower than with the original larger (ETRTO 451) wheels. Back in the day, some export Twentys for the USA market were fitted with 20 x 1.75" wheels due to dealer demand for a US-standard tyre size on the bikes. When these export bikes come up for sale these days most have bent cranks or pedal spindles from pedal strikes. The smaller wheels also dictate flexy and inefficient super-long-reach brake calipers. Tyres more than 1.75" wide will not fit comfortably between the stays or fork blades of a Twenty, so fatter BMX tyres cannot be used to make up the BB height deficit. It's best to use 20 x 1 1/8" (or 20 x 1 3/8") junior BMX race rims - same diameter as steelies originally fitted. There's a very good selction of high performance rims and tyres readily available. The "fattest" 451 tyre is currently Tioga's Powerblock BMX race tyre in 20 x 1 3/8" if you want the bigger tyre BMX look. You should find a replacement fork easily on eBay. There are two types. Earlie ones are cruder, with constant diameter blades and pressed and notched ends. Cheap and nasty! '78 and later forks have nicer tapered blades and proper brazed-in ends with integral mudguard eyes. The later pattern have more resilliance and therefore give a better ride. Cutting new thread on unthreaded steerer is a game of chance, and you're unlikely to get a good, clean thread even if it goes on relatively straight - ask me how I know!!! Original fork threads are machine-cut on a lathe as a bare tube before the fork is built. In my experience, you can't do nice threading on a complete fork. My aforementioned A-Headset conversion solves that problem. For decent alloy brakes on the cheap (when using the proper 451 wheel size) you can use old Weinmann 730 (front) and 810 (rear) brakes, which bolt straight on with no mods. These are common on eBay as they were used in that combination on literally millions of mid-range Raleigh sports bikes through the seventies and eighties. High quality modern dual-pivot calipers, in the form of Tektro R559 or Dia Compe BRS 202, can be used but a mod to the brake bridge will be necessary as the original brake hole is too high. If styling the project as a BMX bike, be aware that the non-triagulated frame isn't robust vertically, so jumps and even curb hops are a no-no - otherwise the bars will creep ever-closer to the saddle and the BB height will self-reduce!!! The big 44mm main tube is very stiff torsionally and laterally, so if styling a Twenty conversion as a touring, sportif or fixed "performance" road machine, the frame will be plenty stiff enough and as just good to ride as a modern steel road frame. You can find the Twenty branded Raleigh, BSA, Triumph, Hercules, New Hudson, Phillips and Sun, as Raleigh Industries had bought all of those brand names. It's "badge engineering" at its finest! The very first batch of Twentys (no steering-stop on the lower head tube and other minor differences), late 1967 into 1968, were actually Triumph branded so as not to directly compete with Raleigh's RSW 16 introduced the year before. The Twenty was an instant hit and eclipsed the RSW! Raleigh and the other brand names were applied from late '68 onwards. More than two million Twentys were made '67-'84 and it was the biggest selling model in Raleigh's long history, with twice as many sold as the closely related Chopper. Let me know if you'd like any further help or advice. Good luck with the project. Loving Raleigh Twentys!!!
Thanks for your information. It was interesting and very helpful.
A tip for keeping threads straight on steerers (not that it would have been ideal in this situation) if shortening a steerer tube, cut threads before sawing the steerer shorter using existing threads to start the cutting die. You end up cutting more threads than you need but it ensures that you start cutting the threads straight.
Very useful info...
What I usually do is tapping new threads and leaving the die in the tube. Then I cut at the desired measure and go back with the die to leave perfect threads behind
@@gennarogiacalone1528 I like your method. Hopefully I can remember if and or when the need arises.
@@gennarogiacalone1528 so u leave original threads on then use die to cut more threads the cut steerer tube then back off the die? Just need a bit of clarification
I would normally do that but with the 26tpi to 24tpi I didn’t even think of that. Every other time I’ve had to cut a fork I’ve extended the threads first.
I feel your pain on the thread cutting angle. Thanks for disclosing both steps and missteps. You are as authentic as the classic bikes you restore. All the best.
Ah thanks! I appreciate that.
Chris Dodds cycles of Nuneaton, that takes me back, had many a bike from that shop as a kid.
Your dedication to the job is impressive! I was looking forward to seeing this bike go on a serious diet and get updated, so hopefully that will happen now
Definitely the updated part! I think I’ll keep the original racks so not sure how much of a diet that will be!
That die was SHARP!
As well as being entertaining this post is also educational but in more ways than one.
The obvious fact is the cost and effort involved is not proportionate to the end result. An old frame like this will never be worth much or more importantly used much.
Im a road cyclist, my friends have modern bikes and additionally a few also have older classic bikes. The classics are void of the modern advents that now make cycling much more pleasant and enjoyable, consequently none of the classic bikes get used.
For those of us that simply enjoy riding we are far better off owning a modern bike.
All the best and keep up the good work Andy
Thanks! The cost and effort definitely out weighs any return in selling value but I think it’s worth it. Lots of folk still use older bikes daily too! My 88 Saracen Trekker with the 3x6 thumbies and canti/u brake is still my daily. It’s an absolute blast.
It's somehow comforting to see you making a major cock-up. It makes me feel better about mine.
Still, my commiserations, and keep those mighty fine videos coming. Thank you!
Great video, really good to show when things don't go to plan. Makes me realise I'm not the only one haha
Definitely not the only one 😂 things get very frustrating at times!
The Dawes kingpin would be a better bet, as the bb is standard BSA thread and it also has a normal headset not that goofy nylon bush as used by Raleigh
I heard about them… after I bought the BSA 🙃
Sometimes you have to test the waters I love you take the step so others can learn keep it up bro 😎
I mean others have done it before but I’m just here documenting my own progress and messing up a bit 😅
I can’t wait for the next one, been eyeing up a Raleigh 20 for a while!
I have one that needs a new home.
Me too. I’m looking forward to see how it rides.
I used the stocks bb cups with slightly smaller metric ball bearings and an old sakae spindle on my 1973 raleigh Grand Prix
This, more or less, is how I’ve set up my Twenty.
I’m guessing that had the 71mm shell rather than the wider 77mm though.
Woo!!! New vid
Look! It’s the Marin man!
@@MonkeyShred your greatest fan
On the bright side the viewers can learn from your mistake. Learned from frontcountry expeditions is to cut threads on steerer tube using existing threads to ensure cutting die is straight. I may not ever use this info but it is nice to know.
Hopefully! I would normally have cut from the existing threads but the originals were 26tpi and I was cutting 24tpi
Great video, looking forward to the next instalment on this project. I'm currently playing about with a very similar frame, a 1979 Triumph Traffic. Encountered all the same Raleigh thread issues. It's the folding version though, I've put a 3 speed coaster brake rear hub on to it, and am trying to keep both half's of the frame unconnected to allow it to be dismantled easier for transport.
Sounds like a plan!
I’ll have a ‘short’ update coming soon regarding the fork. A bit of 3D printing has hopefully solved the issue I had.
You should ask Swytch to send you a tiny front e-wheel!
A little conversion kit like that would be pretty nice on something like this I think. Especially with the front and rear racks.
I thought when I asked you a while back whether you had a facing tool or not that you'd soon end up getting one 🙂
nice purchase and I'm sure you'll get more than your money's worth out of it.
Well it was so cheap in the sales at the start of the year that I couldn’t believe my eyes… I had to buy it!
I've done a few of these Raleigh Twentys - I reckon a 1" threaded BMX fork is the way to go - you'll need some long-reach brakes though 🙂
Bonus with a BMX fork… I could use V brakes!
This is brilliant information for us tinkerers. I’m learning so much from you videos. Good luck with the forks. Would the finished bike be a kind of mini velo?
Something along those lines I guess!
Those forks could be repaired easily , I've done it countless times , if it would help your channel I'll repair them for you
Fortunately they’re cheap enough I can get a spare for under a tenner!
@@MonkeyShred no probs there mate , if your ever stuck the offers there , I don't expect anything just thought I'd offer as I watch your channel regularly, great to see someone doing the same resto mods as myself , keep it up 👍
@@carlwilliams6312 cheers bud. Appreciate that. Thank you
any chance if i sent you a twenty frame you would tap it an face it for me if so how much woul you charge for such a task tyia
Super 👏 🇹🇷🙋🏻♂️
Thanks!
if your cutting threads use abit of oil or WD40
I did.
Seems like you’re getting closer to the moment you’re going to be building your own frame.
In a sense… I have 😅 But that’s for an upcoming vid.
Pity about the thread - been there - done that - 😢 I think it's one of the hardest things to do without access to a real machine shop.
I wonder… maybe I could 3D print a guide…
@@MonkeyShred the only way I have ever managed to get the cutting die on straight is using a lathe with the tube in the chuck and the die against the mandrel but that won't work for a fork unless the steerer tube is long enough to go through the chuck etc.
Another thought: thread cutting dies usually come in pairs, one is straight the other should have quite a taper on one side. The tapered one is used to get the thread started and allows you to get the die aligned, the straight one is for finishing the thread.
Oh! The huge manatee! 😱
Manatee?
@@MonkeyShredYeah that was a gnarly one 🤖
There are a few different ways to fix your BB issues.. Why not just use a repair BB that does not require threads..( you would still need to trim the BB shel to 73mm with a hacksaw or a grinder and file it square) There a re many available for the cotterless style cranks..
By the way, when you are using that expensive facing tool you should NEVER turn it backwards with tension applied as it will damage the cutter , it is a specialized reamer and you should not turn it backward.. As others stated the fork can be repaired by barzing or welding a new piece of steerer tube.. Paul Brodie you tube chanel has a great video on doing the exact thing....
I’d rather have a threaded BB than a threadless and the faces would still need to be faced so the threads would need to be 24tpi still.
Noted on the cutter. I should have really thought about turning it back being a no no.
Yup - I could weld / braze on a new steerer but I think it’s more cost effective for me to buy one of the many cheap spares available at the moment.
Birmingham small arm?
Yep. BSA
If you can get someone to weld another forks steerer, you should be fine
Always an option but replacement forks aren’t too expensive fortunately.