Readers’ Rides: George Thompson’s ‘Making Up The Numbers’ XXL Geometron G1 

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George Thompson’s ‘Making Up The Numbers’ XXL Geometron G1 in ‘snow leopard’ paint finish is certainly eye catching. It might even have him catching up with the rider in front. We did do a slight double take though – because surely at this size, it should be giraffe, not snow leopard?

Why this bike?

At 6’ 6” (198cm) I’ve always had trouble getting bikes that fit. I spent the first 5 years of my DH ‘career’ going OTB on every steep section. Back in the day Chris Porter shortened the shock on my Santa Cruz V10 to increase the reach and wheelbase and I’ve been riding his Geometrons since the first batch of G16s arrived in Monmouth. I can’t say I bought them initially for the long, low and slack geometry; I bought them simply because they were big, but it turned out that Chris knew exactly what he was doing when he designed them. 

I bought this particular frame in 2020 and for a couple of years it was my trail bike. Frame sizes increased considerably and for a couple of years I threw a leg over a Commencal for DH. The high pivot design meant they grow in the travel and the initial V4 felt bigger than the numbers suggested when I rode it. Then in February 2023 I bought an ebike frame (a Nicolai Eboxx) and I stripped the G1 for parts, knowing full well that I’d never ride a trail bike again. For a few months I blasted the Eboxx with its 560mm reach over hill and vale. Then I jumped back on the Commencal for Round 1 of the 2023 National DH Series at Rheola. With its 500mm reach (I was on the second generation V4 now with its not so high pivot), I spent the entire weekend feeling like I was riding a BMX; so, when I got home, I emptied the spares box and built the G1 up for the next round in Fort William. 

I swapped between the Commencal and the G1 at Fort William and National Champs at Bala, and after going so fast on the G1 at Bala that I got lost on track and hit the huge double that I never had any intention of doing, I sold the Commencal a few weeks later.

This year I decided for my first year in Grand Vets I’d treat myself to a custom paint job. We’d run the snow leopard design on our jerseys for two seasons and I was going to change it, but at the end of last season, as I thanked Nick from Man Down Media for including pictures of the team in all his race reports he told me “Those jerseys look so good coming through the trees, don’t change them” so we’re stuck with them now. I think we can all agree Jon Parkin at Flat White Paintworks absolutely killed it with the paint job!

After years in the DH wilderness (midpack at best!) I’ve been on two National DH Podiums already this season and this bike is a huge part of the reason why.



This is the ‘old’ XXL Geometron G1. I’m running the longer (250mm x 75mm) EXT Arma shock which gives 190mm rear travel in short travel mode and 210mm in long travel a la Paul Aston’s infamous set up. Unlike Paul, I’m running it in 190mm travel because the shorter travel has a lower BB height (363mm) and slacker Head Angle. I’d like the BB to be 10mm lower but the longer shock has more sag so the ‘actual’ BB probably isn’t too far off. 6.5mm seat stay mutators and the 54mm chain stay mutators give a 455mm chain stay. With that combination of shock and mutators it left me with a 61.5 degree Head Angle which was a tad too slack so, I’ve got a Works Components 1.5 degree Angle Headset in there to get the head angle to 63. Wheelbase is a whopping 1,410mm but it doesn’t feel that big to ride, partly due to the mullet set up I think.


The ‘old’ 35mm RockShox Boxxer Ultimate with 46mm offset drop crowns set to 200mm travel. The 35mm Boxxers are the only dual crown fork I can find that will fit the XXL G1’s 150mm headtube. Initially, I thought this would be a bit of a concession but the NSR Racing damper (developed by ex-Canyon & Devinci mechanic Nigel Reeve) makes it the best fork I’ve ever ridden. Pressure fluctuates between 130-135psi with no tokens. Rebound 9, HSC3, LSC 7 (all from closed) and serviced by the fabulous team at J-Tech Suspension.


EXT Arma V3. It doesn’t have the spherical bearings that I liked on the Storia V3 which comes with the G1, but it does have adjustable Hydraulic Bottom Out. I’m 105KG in race kit & running a 500 spring. Rebound 4 LSC 6 HSC 7 (again from closed). 

Chris sent me the Arma last year and I spent the rest of the season going back and forth between it and the shorter Storia; I wanted more travel for the bigger tracks, but I just couldn’t get it to feel as good as the Storia. In February we went to Ride Southern Spain for a week, and I left the Storia behind and put the Arma back to the settings it had when it arrived, made the rebound 2 clicks faster and I haven’t touched it since.


Hope Fortus 30 DH wheels on Pro 5 hubs; 29” front, 27.5” rear. I was initially a bit nervous about the Fortus rims as one of my teammates, Binnsy, destroyed one very quickly but myself and another teammate, 2018 Masters World Champion Mark Weightman have been using them for a season and a half now and we haven’t had a single issue. 


Tyre choice for this weekend’s National at Antur Stiniog were Schwalbe Magic Mary’s (Super Downhill). I prefer the faster rolling Tacky Chan but I’m down to my last set and they’re part worn. Schwalbe Doc Blue Sealant and Cushcore front and rear. By race runs I’d ended up on 20psi front & 22psi rear.


Hope 165mm cranks. I’ve tried 155mm cranks but with such long levers I felt like I was spinning out. Hope 34T chainring; I’d like to run a 36T but the 73mm BB combined with the long shock mean that isn’t possible as it catches the frame. I’m running an Ochain in the 12 degree setting. I forget about the Ochain until I ride a bike without one and then I remember how good they are. 

Mech, Shifter and Cassette are all SRAM. Mech has more scratches than a toddler with chicken pox but is still hanging in there. Cassette is the cheaper GX DH cassette. I’d like the X01 DH Cassette as it has a 10T cog but I have 3 wheelsets for racing with different tyres and they’re set up with a cassette and brake discs so I can change them quickly and much as I try not to skimp the GX cassettes are £30 and the X01’s are over £200 each so… Sram 11 speed chain, Blackspire Der Guide which was one of those left over spare parts, STFU chain damper. 


Hope Tech V4 with some custom Making Up The Numbers bling; 220mm rotors front and rear. I was a Shimano Saint man until Hope released the V4 but they’re just incredible and I’ve only bled them once in a year. If they start feeling a bit spongy, I just top up the fluid and it gives them a new lease of life. I’ve currently got purple ebike pads in as I’ve run out of the green race ones. Braided hoses as the cables are externally routed.

Bars and Stem

Renthal Fatbar 35mm, 40mm rise. 800mm wide giving a 1,155mm bar height. For a few years I was riding wider bars (up to 840mm at one stage) but I found that once you get the reach right you can reduce the width of the bars. In Fort William last year I ran a 60mm rise Spank bar because they were the spares I had kicking around, and I liked it and might give it another go at European Champs in Champery where it’s super steep this summer just to try and get the front a little higher. Stem is a Hope 45mm with 0-degree rise. I’ve been told that there is no benefit to matching stem length with fork offset but I like the synchronicity ☺ I’m running the new Ergon GD1 grips. I have hands like shovels so I’ve used Ergon grips for years as they’re generally a bit thicker. These are the regular ones and the first non-contoured grips I’ve used in years and I’m actually surprised I like them, but I do.

Other Bits

Hope seat clamp, Ergon SM Downhill Saddle – it’s just the standard steel one as I’ve bent every TI seat I’ve had; Thomson seatpost which I’ve had since 2008, Crankbrothers Mallet DH pedals and shoes. RRP mudguard, ODI numberboard and Snakeskin protection.

Big thanks to Chris and Marcel at Geometron / Mojo Rising for their time and advice; Claire at Hope for sorting all the bits, Alex at Ticky Bikes for keeping the bike running, Jake at Snakeskin for the wrap and of course John Parkin for the custom paint. The Troy Lee D4 is a “race runs only” lid and yes, John’s done me a spare visor ☺

Thanks to Rachel at Milk It for the photos.

Whether you’ve got a special new bike or just a bike that’s special to you, this is where you get to tell us about it! You send us your submissions, and then we cast our judgemental expert lustful eyes over them and bring them to the world to ooh and ahh over. We’re picking the prettiest, the most curious, and the ones with a good story for you to appraise, praise, and maybe look wistfully at.

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Hannah Dobson

Managing Editor

I came to Singletrack having decided there must be more to life than meetings. I like all bikes, but especially unusual ones. More than bikes, I like what bikes do. I think that they link people and places; that cycling creates a connection between us and our environment; bikes create communities; deliver freedom; bring joy; and improve fitness. They're environmentally friendly and create friendly environments. I try to write about all these things in the hope that others might discover the joy of bikes too.

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Home Forums Readers’ Rides: George Thompson’s ‘Making Up The Numbers’ XXL Geometron G1 

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  • Readers’ Rides: George Thompson’s ‘Making Up The Numbers’ XXL Geometron G1 
  • a11y
    Full Member

    I was hoping we’d see a bit more of the paintjob after catching sight of it in the little crash sequence from Antur…

    Good stuff. Very much a bike specced to suit the rider.

    I’ve also got a Works Components 1.0deg headset in reverse in my G16 to reign back the HA to 62.5ish with my mullet config.

    Full Member

    Congrats on the podium at the Weekend!


    Full Member

    Looks awesome 😎

    I hesitated and missed out on your old g16 a couple of times when you solf it an someone else sold it on here. I thought it would be too tricky to get double crown 29″ to go on it. Every time I get an uplift I curse slightly at the hesitation.

    Maybe I’ll hesitate less if you sell this on in the future 😃 at 6’3 its probably one of the very few bikes that are too big for me

    Full Member

    You boys always impress me at races, lots of team spirit, determination and always enjoying it

    Pleasure to share the paddock with you even though I’ve never spoken to any of you.

    Full Member

    Thank you for the kind words everyone! For anyone wanting to keep up with the team’s endeavours we’re vlogging this season

    Full Member

    What a fun, and unique bike. I was just writing on another forum, that a DH bike seems interesting, but they don’t come in decent sizes. I guess this is the answer.

    (6’5”/196 cm here).

    Full Member

    Love a bright, fun paint job.

    Full Member

    Thanks @tjaard! I think the most important thing when it comes to bike design is that it fits. Travel, kinematics etc are all important but you’re just polishing a turd if it’s the wrong size. I’ve found that 550mm reach with a 45mm stem or 560mm reach with a 35mm stem seems to be the sweet spot for me but interested to try the new G1 which has shorter reach & longer chain stays at some stage!

    Full Member

    @rockitman I agree that fit is the most important (but then I would, I’m a bike fitter, 🤣). As I’m sure you know, we have to use both stack and reach when we talk about frame size. Lower stack = adding headset spacers to get the same fit, and with modern, slack bikes, the relationship is about 0.4 X stack = reach. Ie, for every 10mm less stack, you end up 4 mm shorter in reach once you add headset spacers (or another part like stem or bar) to compensate.

    Every bike I’ve bought over the last couple years has been bigger than the last, currently on a S6 Stumpjumper Evo. Feels pretty good from a size perspective, but it would be interesting to ride a bike and find out it’s too big, as I’ve never experienced that yet. The Geometrons would be the ones to make that happen.

    Since I work at a bike shop, that means fortunately, I get huge discounts on bikes. Unfortunately it also means I need to stick with brands we sell (currently Trek, Spesh, Santacruz and Salsa).

    For you, even taller than me, and racing DH, Geometron must have been a godsend. I didn’t remember that they made such a long travel version.

    I don’t know about the G1, but I think the new Geometrons have taller stack, which would be nice, except it might get you into trouble with running a dual crown fork?

    And agree, awesome to see a cool paint job!

    Full Member

    Interestingly, until I bought the Eboxx I hadn’t ridden a bike that was too big since a Raleigh Grifter in the early 80’s. Eboxx has 560mm reach & with a 50mm stem it was too much.

    New Geometrons do have taller stack. I need to have a chat with them because on the XXL the head tube is 170mm & I don’t think there’s a dual crown fork that will work at that length unfortunately but I could be wrong :)

    Full Member

    Many thanks for sharing this really enjoy reading about the small details each rider has etc. Love the paint job too, keep up the good race results :)

    Full Member

    I really enjoyed this write up.

    Your type of bike and riding is so far from what I do the spectrum needs to be redefined but I love the detail and the technical bits.

    I’d never heard of Ochain before reading this ( what a fantastic piece of kit :-)  – Not sure my Orange Gyro warrants one though …

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