Category: Tech Talk

Technical information about Bird frames and products

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Big, Big or Biggerer? New wheel options available now.

At Bird we’re fond of pushing something good when we believe in it fully. We’ve always been fans of big rims, and we’re happy to announce 3 new wheels for the line up, available going forward.

30mm M502 DT Options and 35mm Hope options now available.
For those who’ve never tried it, widening your rims has some pretty awesome effects on tyre stability, which lets you run pressures you probably never thought you could. Lower tyre pressures in turn offer much greater traction and stability to the ride, as well as comfort. Its a win-win situation. Not only that, but lower pressures don’t slow you up, infact many studies have concluded that lower tyre pressures don’t increase rolling resistance by any notable degree. The ability to deform to the contours of the trail give huge increases in grip, without notable disadvantages.
Recently there’s been a few ‘Plus’ bikes cropping up, well more than a few! We got in early with the plus testing, and gave it a punt, but it didn’t really work out for us… I’m not going to get into a dissection of Plus tyres though, thats a fad already fading, so we’ll move on.
Instead lets look at what is commonly becoming known as the ‘Wide Trail’ format. This was pioneered by perennial tyre gurus Maxxis, as a better standard than the current non-standard for normal tyres. What you need to understand I guess is that normal tyres have no rim standard to go with. Rims, specifically the width, change the tyre profile. That changes the ride. Over the last few years we’ve seen common rim widths rise from as narrow as 17mm to 30mm – nearly a doubling of the rim width, but with no consideration of such for the way a tyre sits on the rim. The wider the rim, the taller and squarer the tyre becomes, both at the cap (the tread bit) but also the sidewalls (the bit you always put slashes in). Squaring up the tyre has disadvantages and advantages:
Disadvantages:
  • The tread can become too flat, increasing drag, and meaning the side lugs run out of grip too soon, or are too ‘edgy’.
  • Sidewalls can be perilously exposed beyond the tread, making tears more likely.
Advantages:
  • Squarer sides give better support, so reduce squirm and squish, particularly in corners, at low pressures.
  • low pressures available thanks to point 1, give increased traction at the tread

What is Wide Trail?

Wide Trail (WT) is the moniker Maxxis gave to tyres designed specifically for wider rims. They are NOT plus tyres. Hell, they aren’t even half-plus in many ways. Plus is a new direction that sets its own path, while WT evolves the existing with an updated way of thinking. When Maxxis launched Wide Trail tyres, they also stated ‘these tyres are optimised for 35mm internal rims’. As we’ll discuss later optimising is not the same as set in stone, but at least they made their stand, they called a rim width out and said ‘this is it’. Someone, somewhere, thought about the their best combination of the variables available and made a call. That is the big deal here. Plus on the other hand is not so well defined. Why does this matter? Well I guess it does for many reasons, but really it matters because theres a range of rim widths and bike designs for Wide Trail that works properly, and a range that doesn’t, and thats kind of it. For the first time someone is saying ‘This tyre, this rim.’ No messing, no pretending its the best new thing ever, just a statement of intent. Stick within the boundaries and you’re all good.
Wide trail in essence is tyres deigned for 35mm rims. Bigger tyres, designed for 35mm rims. Thats it. No magic, no marketing BS. Just thoughtful design.

Why Should I Care?

OK, not the first time I’ve used that title in a Facebook Note, I apologise for the repetition. You should care though because Wide Trail, and the many variants of that which other manufacturers, not allowed to call their tyres ‘wide trail’, but serving the same purpose, IS the future.
I’m quite lucky I guess. I get to try things much earlier than most people. I’ve had WT tyres since before most of the people reading this knew it was even a thing. And I like them. I like them a lot, because it serves a very obvious purpose, improving grip without too many compromises. Thats something I, and I guess you, can buy into.
Boost, or not so much?
One point worth noting, but not labouring is Boost, and what it offers, or rather doesn’t. You may notice that our new bikes, the Aeris 120 and 145 are both Boost-ed. Boost is basically, for those who don’t know or really care, a 6mm wider axle spacing than a normal bike as has been for ever. For the longest time the rear axle spacing on your bike was effectively a 142mm spacing (even if it was 135 QR – its the same in essence) but now its moved to 148mm, so 6mm more. Both sides of the bike at the back are 3mm wider, which gives more room for your tyres… Sort of.
The sort of comes from the fact that 3mm either way is, well, not that much. Squeezing in all the stuff you need to race an FS bike meant that when you accounted for mud, and I mean proper, British mud, even a 2.3 was a pinch on most bikes, impossible (even in the dry) on some. Boost translates to 0.19 of an inch either side, so 0.38 Inches in total extra width. Supposing you had a 2.3 tyre in a non-boost frame, you could move to a 2.68 tyre in a boost frame easily enough. Well nearly… Boost however doesn’t account for lack of change in q-factor, essentially the width of the cranks at the tip, so even though you get a theoretical .38 inch gain, when you take into account the fact that you need to cut the chain-stays in to their original width at the crank tips for the unchanged q-factor, you’ll find boost doesn’t really offer you that gain. Its a little less. Let’s call it 0.3 inches for now. Boost gets you to about a 2.6 tyre in terms of modern bike design without significant messing about. Now you maybe start to see why 2.5/2.6 is probably the future? Sure we can mess about with oddball split chain-stays etc. to get a 2.8 or 3.0 tyre in there, but ask yourself (especially if you’ve ever owned a very tight clearance FS bike) ‘Why didn’t you do that for me before?’. There are good, and not so good reasons, but what you need to take away from this is that Boost doesn’t equal plus. Not even close.

The New Options (on your next Bird)

So heres the fun bit, for me at least. We’ve got some new options coming online for you, that we’re really happy about. 3 new wheel-sets that offer versatility and future-proofing, as well as being pretty damn cool among your riding buddies 🙂 They are:
  • DT 350 Hubs with DT Swiss M502 30mm* rims
  • Hope Pro 4 Hubs with DT Swiss M502 30mm* rims – coming soon
  • Hope Hoops Pro 4 Hubs with Hope 35W 35mm* rims
* Given widths are internal width.
I should say at this point I am a wheel geek. Proper geeky. Nothing gets me excited like a new wheel to build. For me wheels are the my favourite bit of a bike to perfect after shock tunes. I leave the really tricky stuff to Dan, and simply lean over his shoulder occasionally and shout things like ‘It needs to be slacker’, or ‘Make it prettier’. My technical input is limited by my lack of technical FEA/CAD/Super-techie-engineering-knowledge at best in such matters, but when it comes to wheels, thats a whole, big, other story.

30 vs 35?

We’re launching** wheels in 30 and 35mm widths, and that’s where it’s important to understand what that means for you, the bike buyer. Specifically what’s the difference? Well 30mm will run current and WT tyres, while 35mm won’t really. Its not to say your wheels won’t go round, or you won’t enjoy it, but I think the cut off for non-WT tyres is around 32mm internal width. Bigger than this and the drawbacks begin to outweigh the benefits on non-WT tyres. They get too square, and the sidewalls too exposed. It’s a word of caution I guess. If you’re going wide, 30mm is as wide as you can go and still have all the tyre choices available to you. At 35mm you are committing to WT as far as I can see. Thats not necessarily an issue of course, as long as you don’t mind the cost. While we’re starting to bring in WT tyres direct from the Maxxis factory, reducing the cost to you the buyer, its still a significant premium option at the moment. WT style tyres are appearing at a significant rate – you wont be short of options, but you might find a 30mm rim offers more options right now at a better price than 35mm.
** Technically we launched the DT 350/M502 wheels months ago, but hey.
Can I run WT on 30mm?
From my view, the answer is a resounding yes. While the stated optimised width is 35mm, I’ve found 30mm to be very effective. Its also bourn out in the numbers. Comparing a Minion DHF 2.3 and WT 2.5 gives the following widths:
  • Minion 2.3 (standard) on 30mm Rim: Tyre width = 2.26 Inches
  • Minion 2.5 WT on 30mm Rim: Tyre width = 2.42 Inches
  • Minion 2.5 WT on 35mm Rim: Tyre width = 2.46 Inches

L>R Minion 2.5 WT on 35mm rim, Minion 2.3 on 30mm rim, Minion WT 2.5 on 30mm rim. Note the block size, significant width and height differences.
You will no doubt see the WT tyre sizes up very similarly on a 30 and 35 rim. I’m personally running WT tyres on a 32mm rim right now, and I’m happy with the results. Perhaps its compromised over a 35mm rim, but its still good!

What Else Do You Need to Know?

Well, WT tyres are taller, thats an important point, its not the be all and end all, but it sneaks the 27.5 tyre size towards its ultimate pinnacle of being genuinely half way between 26 and 29 inch tyres. It improves the roll over a little and offers even lower viable pressures.
We’re offering 3 new wheel sets, and of course weight is always relevant. Real weights are:
  • DT 350 Hubs with DT Swiss M502 30mm rims – 1908g
  • Hope Pro 4 Hubs with DT Swiss M502 30mm* rims – 1999g
  • Hope Hoops Pro 4 Hubs with Hope 35W 35mm* rims – 2100g
Tyre wise the options opening up for you in WT are:
  • 2.5 WT Minion DHF 3c Maxx Terra
  • 2.4 WT Minion DHR2 3c Maxx Terra
  • 2.5 WT Shorty 3c Maxx Terra
  • 2.5 WT High Roller 2 3c Maxx Terra
  • 2.5 WT Minion DHF 3c Maxx Terra Double Down
  • 2.5 WT Shorty 3c Maxx Grip Double Down
… with more to come!
I hope thats been a worthwhile 10 minutes of your time, any questions mail us at info@birdmtb.co.uk!
Ben
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Everyone needs a new bike day now and again.

Its not so long ago, just a few weeks in fact, that I broke my arm racing at the Welsh Gravity Enduro Series. While the healing process has been quick enough, and relatively painless all things considered, it’s still fairly weak, and the range of movement I have right now is somewhat limited.

Me, broken.
To help me get back on the bike, I decided to build up myself an AM to keep in the van, ready to snatch a ride whenever the opportunity occurs. For this type of endeavour the hard tail is the weapon of choice, ride-rinse-ignore-repeat. It just has a certain bombproof-ness that suits a winter ride that a full suss will never match. While this probably doesn’t sound so unusual to most people, you might be surprised to hear I don’t personally own a bike right now. At least not a whole bike, and certainly not one that is readily available. I split my time between Bird HQ and the far north east of England where I live, and I really only ride whatever happens to be available from the demo fleet, or any prototypes that are lying around. For the last 3+ years since Bird started I’ve never actually owned a bike, 100% complete, that I could call my own.

The Mean Green Machine

Deciding to correct this anomaly in my life, I set about building the mean green machine. Its based around a standard spec AM with a few tweaks to make it my own, and I thought I would share it with you.
I decided to go with a medium, an unusual choice given my penchant for longer bikes, but the limited range of movement on my arm, combined with wanting something for quick blasts when I could meant a medium suited me better right now. Size is an interesting thing, we often get asked “what size should I buy?” and while we try and offer the best advice we can, it is ultimately a personal preference. I can easily ride a large AM as well as I can a medium, but on this day, a medium was just the better choice for what I wanted.
I decided that this build would be stealth black and green, mainly because I had some green hubs that I’d had made for me knocking about, but also because the stealth black is a bit of a labour of love for me, having spent a long while getting just the finish I wanted from the paint-shop, so it seems only right I went with that.

The Mean Green Machine

The Specification

Everything starts with the specification when we build a bike for a customer, and for me it was just the same. I decided to go pretty high end on this one, throwing caution into the wind and instead making the very best AM I could from the parts I had available.
  • Bird Zero AM – Size M, Stealth Black
  • RockShox Lyrik RCT3 160* SA, Stealth Black
  • SRAM Eagle X01 drivetrain
  • SRAM Eagle X01 Carbon cranks, 34T
  • Hope Stainless BB w/GXP conversion
  • SRAM Guide RS Brakes
  • SRAM Centerline 200/180 rotors
  • RaceFace Turbine R 35 Stem, 40mm
  • RaceFace Next SL 35 bars, 760mm, green
  • RaceFace Half Nelson grips, grey
  • Cane Creek 40 headset
  • RockShox Reverb Stealth 170mm, left hand under bar
  • Fabric Scoop Race Saddle, Ti rails
  • One Up Bash Guard
  • RaceFace Chester composite pedals, green
  • Prototype carbon rims, 32mm internal
  • Custom made hubs, 142/12 & 100/15mm, 28h, XD driver, green
  • DT Swiss Competition spokes w/Pro Lock Squorx brass nipples
  • Maxxis Shorty 2.5WT Exo TR Maxx Terra up front
  • Maxxis DHR2 2.3 Exo TR Maxx Terra out back
  • RockShox Maxle Ultimate, 142/12
* The Lyriks are currently 160mm, but unlikely to stay that way. I will probably chop out the air shaft for a 150 or maybe even 140mm air shaft, but I figured I would try a 160mm hard tail out to see how it goes before doing that. Testing whenever we can is part of our ethos in order to find out what works and doesn’t. I should point out that running a 160mm fork on your AM will invalidate it’s warranty!

The Build

First thing to do was make some wheels. If you ever fancy building your own wheels, I can strongly recommend you build them with carbon rims. Building carbon wheels is ludicrously easy compared to aluminium rims. The stiffness of the rims means its very easy to get them straight and round with minimal effort. Whereas an alu rim will deflect and go egg shaped relatively easily with moderate variations in spoke tension, a carbon rim defiantly wants to stay true and round unless you really mess it up.
The rims I used are some new 32mm internal rims from one of our manufacturers. I’d specced them up with an ‘enduro-proof’ layup, blending strength where its needed with some weight saving where its not, to give a stiff, strong rim that was not too heavy. We’ve broken enough rims here at Bird to know what needs to go where, or at least I think we do. They could be lighter, but I wanted them to last. Paired with 28 DT Swiss Competition spokes per rim, they are a cost effective, mid weight option, perfect for this build. Brass double head DT squorx pro-lock nipples finish off the build. These nipples are perfect for carbon rim builds, and I had the rims custom drilled to ensure that not only were the nipple angles exactly as I wanted them for my hubs, but that building from the back, as is the best way, was a cinch. Thanks to Dan for doing me some nice technical drawings just for the hole drilling! It’s all about the details…
The hubs are made by a small machine shop in Taiwan, that specialises in high end hubs.

Sometimes to get what you want you need to go the extra mile.
They are based on a standard DH offering the hub co. makes, but I had them machined out to save weight while keeping the nice big bearings, and adjusted for a 12 and 15mm axle 🙂 I would normally go straight to Hope for my hubs, but they won’t supply me green ones, and I wanted green, so custom it was. These come in around 30g lighter after all the extra machining than a pair of Hope Pro 4s too, which is a bonus. The quality of the manufacture is excellent, and the sealing is first rate, so I have high hopes for these. My one gripe is that while I asked to trim the flange width a little to save weight, I should have done my homework a bit better, as the DH-spec flanges on these hubs are still very fat, and that means the spokes don’t sit perfectly in the holes, as the J Bend is a little too abrupt to work its way round the flange thickness, but thats a small complaint I guess. Next time I will fix that up.
Weight-wise the wheels run at just over 1750g for the pair. Not the lightest wheels I will ever build up, but they certainly feel like one of the stiffest I’ve ever built, and they should last forever!

Assembly

Wheels built, the rest of the bike is of course a breeze. We build alot of bikes here at Bird, everyone built by us to order, so assembly is pretty much a doddle. There’s a few steps you probably don’t realise we do though, before a Bird gets assembled, including:
  • We tap every BB shell again, no matter how good it looks, to ensure that its clean and ready to have the BB fitted.
  • We tap the ISG05 tabs, and the maxle threads
  • We check the seat-tube ream
  • We check the facing on the head-tube and BB to ensure its perfect
  • We inspect the paintwork end-to-end to ensure its chip and mark free
  • We check the alignment of the bike to ensure it is straight, and the brake mounts are straight too
You’d be surprised what you’ll find on many bikes if you look closely. In my lifetime I’ve seen some real doozies from big manufacturers, leaving me scratching my head wondering “how on earth does this stuff pass QC?”, here at Bird, even our personal bikes get proper quality control before they leave the workshop, and yours more so (I must admit not checking the paintwork on my own bike 🙂 ).

Parts Highlights

The highlight of this build for me has to be the Xo1 Eagle. SRAM’s new 12 speed groupset. Its a joy to use and offers a massive 500% range from a single shifter. It really is a game changer. The shifting is so precise its crazy, and the adjustment you get from the shifter brake combo is huge too, allowing you to easily set up the shifter just right for you. With 2 horizontal positions, about 45 degrees of fore-aft rotation, and an adjustable downshift lever, the SRAM set up on X01 is about as good as it gets. The shifting is incredible, so quick and smooth its like its not happening, and the 12 speed cassette weighs very little for its size. OK so its expensive, but when you see the detail thats gone into it, you start to understand why.

160 party up front, all serious out back. The X01 Eagle drivetrain provides some real XC capability.

The machining on the X01 (And XX1) cassettes is mentally intricate.
One thing you probably don’t know is that Eagle cassettes run narrow-wide rings on the biggest two cassette cogs. This is to eliminate the dropped chains from back / slack pedalling as far as I know and have experienced, and it works. Oddly, although it probably shouldn’t you never experience a mis-match between chain and cog either. The chain finds it’s paired thick-thin quite happily with every shift.
Drivetrain selected, the rest of the parts are an easy choice, balancing weight and strength at every opportunity. I decided to go big on the rotors as the Guide RS brakes offer excellent modulation even on the biggest rotors, and went in for the 170mm reverb as well, something with my stumpy legs I can’t normally quite manage, but given this is a medium AM I could just squeeze it in.
A first for me was composite flat pedals. I used to be 100% clipped in, but overtime I have begun to appreciate the benefits of flat pedals paired with good shoes. This time of year I am running FiveTen Freerider Elements, a shoe I can’t say anything bad about, other than there’s no black & green version. Paired with the Chester composite pedals its a great combo. The Chester is light and had a good size platform, and runs a screw in pin and nut system, which is great as it means that you can loose a pin through smashing it out and still pop a new one back in no hassles. The Chester isn’t the grippiest pedal I’ve ever run, but to be fair, I find the grippiest ones a bit weird to ride on, offering so much grip that you struggle to adjust your foot position when you’ve got it somehow in an awkward position. I actually prefer the ‘medium’ grip of the Chester I think.

Plastic Fantastic. Composite (Posh word for plastic) pedals are becoming increasingly common on the trails, and for good reason.
Other parts of note might include the One-Up Components Bash guide. Again an often asked question is “Do I need a chainguide?” The answer is both yes and no. No, because chain drops are a rarity nowadays with the various thick-thin chainrings we supply, but yes, because even that is not 100% reliable, especially as the ring wears, but more important is the ‘bash’ part. The chainring on those X01 cranks is expensive. Very expensive. It runs at £87 RRP. That’s not a typo. OK, so if you run X01 Eagle you’re likely aware of its running cost, and thats not an issue for you I guess, but chainrings, especially on low-BB bikes like ours are exposed to all kinds of nasty rock and log strikes that will turn your lovely chainring into a pringle in a heartbeat. The investment in a bash guard, with the added bonus of a silent, friction free top guide to go with it is a very sensible one. It weighs next to nothing, never wears out and might save you a fortune in chainrings.

An expensive chainring protected by an inexpensive bash guide.
Other little tweaks just for me include using a second clamp for the right brake. Maybe I have short thumbs, maybe I am weird, but I prefer splitting up my Reverb remote from the brake in order it can be closer to the grips. It’s just a nicer position for me to use, meaning everything is where it should be, although the aesthetic purists will of course hate it 😉

Bucking the trend with a second clamp for the Reverb/Brake combo
Up front its a RaceFace triple whammy with a Turbine R 35 stem in 40mm, Next SL 25 bars in 760mm width, and Half Nelson grips. Is this the perfect set up? Maybe? The Turbine R is probably not a stem you’ve heard of, I think its OE only, but its actually an Easton Haven stem with RaceFace logos. The Easton Haven is probably the nicest stem thats come out from any manufacturer in modern times, made only better by putting RaceFace logos on it (RaceFace bought Easton a few years back so its no surprise they’ve begun to migrate Easton’s MTB range over to RaceFace and leave Easton to focus on the road side). I’ve plumped for a 40mm here, as the medium AM would be a touch short for me if I went smaller, but we do now stock the strap-the-bar-to-the-steerer 32mm length too. A dinky stem indeed and fitting for our long reach short stem philosophy. If I could change anything I would add maybe 15mm to the Next SL bars, as 760mm is a touch narrower than I am used to, having ridden Sixc and Atlas so extensively over the last couple of years, but its still a good size, and I will happily trade the extra length I could get from a Sixc bar for the feel and weight saving to be had from a Next SL on this bike.

Can different logos make a product better? Yes they can.

The First Ride

I won’t bore you with telling you how awesome this AM is. If you’re reading this then you probably know one of two things:
  1. You own an AM and you know its awesome
  2. You know I am a founder of Bird and so unlikely to say anything bad 🙂
Either way, extolling the virtues of my new bike is probably pointless, so instead, I will tell you how I feel about it. Its so nice having a bike thats genuinely mine again, I can’t really say. Its a labour of love, built over about 6 months when you take into account the hubs and rims, which I am 100% happy with the outcome. This bike will provide me smiles for miles I am sure, and thats the way it should be. Whether you buy a stock bike, custom build or do something between the two, there’s always a Bird that will put a smile on your face and remind you why you ride.
Ben.

First ride day is special no matter how many bikes you build.
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Tech Talk: Tuning Air Forks With Tokens

When RockShox introduced the revamped Pike, they brought with it Air Tokens. They were not the first to allow you to adjust the air volume of their forks, but they were the first to make it mainstream. Those innocuous looking little red plastic blobs that shipped with your fork started a revolution. 2 years on, the little red blobs are grey, and pretty much every manufacturer has something doing something similar in their forks now, but what are they for and why should you care?

Second time luckier. The Pike Mk2 was the one that changed it all.

Why Should I Care?

You should care because if you’ve not messed around with the air tokens in your fork, you’re probably not getting the best performance you could. Its a very cheap and easy way of transforming your suspension to behave in a way that suits you and your riding style, without the expense of custom tuning.

How an Air-Spring Works

To understand what the tokens can do for you, we need to first understand how an air spring works. A normal* coil spring exhibits behaviour known as being linear. What this means is that the spring inside a coil fork will require the exact same force to move it 10% of its travel whether its at the start or end of its travel. On the other hand, an air spring exhibits whats known as progression. Progression means that the air spring will require less force to move it 10% of its stroke at the start of its travel than the end. There are other forces at work such as stiction (STatic frICTION) and damping, but the spring is the basic mechanism of making your forks bounce, and so deserves your attention.
* Progressive coil springs do exist, achieved through using variable coiling, but we’ll not worry about that now.
To put that in simple terms, imagine you are loading weights onto the ends of your bars to compress your forks. You might need 100KG to compress a fork from 0% of available travel to 50% of its travel, but you might then need 200KG to get through the second half of the forks travel. So you needed 300KG of weight on the bars to get from fully extended to fully compressed, but:
100KG of that got you half way 200KG might have got you 4/5ths through The final 1/5th of the travel needed another 100KG In practice what this means is that the deeper into your travel you get, the more the forks resist compression. Useful to prevent big bumps eating too much travel when you have nice small bump compliance, and vice versa useful to prevent you having to run too much air in order to hold the forks up, killing your small bump sensitivity.

What Do the Tokens Do?

Tokens reduce the volume of air inside your fork. This links to the important concept that the increase in spring rate (the progressiveness of the air spring) relates to the reduction in its volume as it compresses, in relationship to its total volume. Sounds complicated? Its not so bad. What it means is that the progression is relative to how much you reduced the volume by as a percentage, not the actual volume lost. So we think of 50% of the air spring volume, not 50 cubic centimetres.
The tokens take up space that would other wise be filled with air, and hence part of the air spring. Say your fork had 100mm of travel. With no tokens in, using all your travel might have used 60% of the available air volume, squeezing all the air into the remaining 40% space. If you added a couple of tokens, the fork might now use 80% of the available air volume in compression, squeezing the air into the remaining 20% of space. Its this adjustment in the relative volume of the air spring that changes to progressiveness of the fork.

May the Force be with you, and progressive.

My Forks Have Tokens in From The Factory. So I’m Done Right?

Probably not. The factory installed tokens are there to adjust the base spring volume from what it would be at the forks maximum possible travel version, to the one you have bought. By adding tokens, the manufacturer is attempting to correct the air spring progression so its roughly the same feel whether your fork is 120mm, or 180mm travel. Put another way, without a good slug of tokens a 120mm fork would blow through its travel so easily it would be basically useless, assuming of course it is a RockShox 120mm fork based on a 180mm chassis like a Lyrik or Yari. With each step down in travel (10 or 20mm) the manufacturer will add another token to compensate for the air volume, but that doesn’t mean its right for you.

When Should I Use Tokens?

This is the million dollar question, and the one to which there is no real definitive answer, but here’s some useful guides as to when tokens might be needed, or maybe need to be removed**.
Scenario 1: You set your sag properly, and the forks feel great on the small stuff, but even moderate trails, rollers and berms are using all of the travel in the fork. Solution: Add token(s) & maintain fork pressure. Scenario 2: You’ve got the forks running sweet when they are deep into their travel, holding you up well and using their travel at just the right rate, but they feel harsh on the small stuff, and the bar buzz is killing you. Solution: Add token(s) & drop fork pressure.
Scenario 3: Your forks feel great at the start of the stroke, but you’re rarely reaching full travel, possibly as little as 50% travel.
Solution: Remove token(s) & maintain air pressure.
Scenario 4: In order to get a decent amount of travel from your forks you’re running them so soft that you have used 30%+ of your travel just getting to sag point.
Solution: Remove token(s) & increase fork pressure.
** Removed? WTF? All I ever hear is people telling me to add more tokens!? Well tokens are a double edged sword, too few and you risk blowing through your travel or running your forks too hard, too many and you’ll never get full travel from your forks. Its worth considering both adding and removing tokens depending on what you want to achieve.
A quick note on ‘maintaining air pressure’. Above I list 3 air pressure options, drop, add or maintain. Maintain doesn’t mean literally keeping it exactly the same, but rather that the pressure you’re running is about right, and its the progression in the spring thats wrong. Changing the spring progression using tokens will effect the fork across the whole of its travel range, so some tweaking of the pressure might be needed to compensate, but its not the main factor at work here.

OK, I’m Sold. What do I Need?

There are four basic things you’ll need to make the magic happen.
  • A socket or good quality spanner to fit on the air top cap. A decent wide adjustable (30mm) spanner is fine for occasional use. It might fix something around the house too.
  • A token compatible fork as found on almost all the Bird bikes. See below for the RockShox compatible fork options.
  • Some tokens suitable for your forks. You probably received some with your forks or bike, but you can always buy some more here: http://www.bird.bike/?s=token&post_…
  • A good shock pump. Specifically one good shock pump. You may own more than one. When testing your set up, always us the same pump. Even the same pumps from the same brand can yield different results when using two pumps. Its always best to stick with a single pump as no-matter how inaccurate, its likely to be consistent, which is the main thing. Its not actually important whether it reads 100PSI but its actually 120PSI. What counts it that when you pump it to 100PSI its the same pressure as the last time you did that.

RockShox Token Compatible Forks and Base Settings

The following chart shows the travel options for each RockShox token compatible fork, and how many tokens you should expect to find under the top cap should you open it up.

How many tokens did your fork some with?

A Rough Guide to Get You Started

As I mentioned earlier, there are no hard and fast rules on the use of tokens. Every one is different and what suits you might not suit someone else. However, as a starting point, I would recommend for the average weight, average trail rider:
  • 32mm Chassis Forks (Revelations etc.) – As from the factory.
  • 35mm Pike Forks (RC & RCT3) : +1 token for every 20mm away from the max travel of the fork (160mm on a 27.5) + 2 tokens.
  • 35mm Yari and Lyrik Forks : +1 token for every 20mm away from the max travel of the fork (180mm on a 27.5) – 1 token.

Recommended tokens shown in blue.

So How Do I Do This Then?

OK, so you’re going to go for it! Good stuff. Here’s the guide from RockShox on how to do it, but don’t worry its not hard.

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Ben