Transition Sentinel Alloy GX Bike Misty Green
Transition Sentinel Alloy GX Bike Powder Black

Sentinel Alloy GX Bike

Regular price £5,399.95 Sale price£4,319.96 Save £1,079.99
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Bike and frame supply has vastly improved since the pandemic, but pre-ordering is still essential for some models and sizes. Hope HB916 frames are made to order too, so we have updated our pandemic bike deposit policy to take the current situation into consideration.

Please note - we can only deliver complete bikes to UK Addresses.

The ETA's (estimated times of arrival) we quote are from the information provided by the manufacturers and distributors. These dates are not guaranteed, as the manufacturers are also at the mercy of component suppliers. We will tell you the same dates as the manufacturer tells us.

We only take deposits on bikes we have on order with suppliers and have confirmation that we are going to receive them. We want to make it clear that there might be issues outwith our control that will prevent us from supplying the bike you want. If that happens, we will do our best to provide an alternative.

Deposits are non-refundable, except for when an ETA date changes by a month or more. If it looks like the date might change, we will do our best to find you an alternative.

If a bike arrives earlier than expected, it will be offered to the person with the oldest outstanding deposit, then the second, and so on. We'll then offer the bike to anyone with a similar bike on order. We should point out that this is a rare occurrence!

Bikes and frames up to £3500 require a £500 deposit.
Bikes over £3500 require a £1000 deposit.

We ring-fence deposits in a separate bank account until the balance of the bike or frame is paid, then the bike or frame is delivered.

We've tried to be as honest and open about the situation as it stands and not make promises we know we are not in the position to fulfil! We have great relationships with our suppliers, and we will work with them and you to try to get you your bike as soon as possible.

If you've read this and have any questions or would like to place a deposit, please phone us on 01330 828562.

We offer free UK delivery on all bikes unless bought through a Ride To Work Scheme.

We don't currently deliver complete bikes outside the UK.

Custom-built bikes can be delivered in kit form (for you to assemble) - we can include shipping to your country in your quote.

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This information is intended as a guide only.

Cycle To Work is a Government Initiative to encourage cycling to work. The idea is that by cycling to work, you get fitter and healthier, and at the same time reduce congestion and improve air quality.

In simplest terms, your employer pays for the bike, and you hire it from them through salary deductions. At the end of the hire period, the employer can sell you the bike. (Until the bike is paid for, you hire it from your employer, so don't get fired).

Your employer might administer the scheme themselves, or use a third party like one of the following:

Green Commute Initiative
Cycle Solutions
My Benefits World

If your employer doesn't offer Cycle To Work as a benefit, you can send them this employer information from the Government that outlines how it all works.

For more information, click here to contact us or call 01330 828562.

We're delighted to announce our first ever demo weekend!

Date: 29-30th July
Location: Tarland Trails, Pittenderich

With over 70 bikes available to test from Deviate, Marin, Nukeproof, Transition and Yeti, this is a unique opportunity to demo some incredible bikes at Aberdeenshire’s leading trail centre - Tarland Trails Pittenderich.

New-for-2023 models from Deviate, Transition and Yeti willbe available and staff from every brand will be on hand to assist and answer any questions.

Cost per demo is just £5 per bike, with all proceeds
split between Tarland Trails and Aberdeenshire Trails Association.

Book Your Demo Here

The Sentinel is a bit of a do-everything bike in the Transition range, up for all-dayers in the hills or uplift days.

Out of the box, the bike is set up with a 150 mm shock and 160 mm fork, but the bike will still handle well with a 150 or 140 mm fork. You can change the rear shock for a shorter one to run the back at 140 mm if you prefer a shorter travel bike.

Transition have given the longer-lower-slacker approach a name - "Speed Balanced Geometry" - but effectively it means short stem, slack head angle, short offset fork and a longer top tube, pretty much what you would expect from any modern enduro-orientated bike. On that note, all models can take a water bottle, though you'll need to use a fidlock bottle on the size small frame.

Never ones to shy away from a cheesy name, the Transition's "GiddyUp" suspension has fantastic small bump sensitivity and enough progression to run a coil shock without blowing through the travel. The Enduro MAX bearings and additional bearing shields are a huge plus point for UK riding!

This GX spec bike has a great spec, with TRP DH-R brakes, Fox Performance Elite suspension and an excellent OneUp dropper post. Dropper size and bar rise vary depending on frame size.


Frame Sentinel Alloy Frame, 29” Wheels, 150 mm compatible with 140 mm Travel, Speed Balanced Geometry, GiddyUp Suspension Platform, Internal Dropper Post & Rear Derailleur Routing, Post Mount Disc Brake, 148x12 mm Boost Thru- Axle, 73 mm Threaded BB w/ ISCG05 Tabs
Front Suspension Fox Float 36 Grip 2 Performance Elite, High & Low Speed Compression & Rebound Adjustment, 160 mm of Travel, Air Sprung, 110x15 mm Kabolt Axle, 44 mm Offset
Rear Suspension Fox Float X Performance Elite 2 Position, Compression & Rebound Adjustment, 205x62.5 mm, Trunnion Mount Top / 25 mm x 8 mm Bottom
Rims DT Swiss M 1900 Spline 30, Disc Specific, 32H, Tubeless Compatible
Hub Rear DT Swiss 370 Ratchet LN, 148x12 mm, 6 Bolt
Hub Front DT Swiss 370, 110x15 mm, 6 Bolt
Spokes & Nipples DT Swiss Champion
Tyres Front: Maxxis Assegai 3C EXO+ (29x2.5) , Rear:Maxxis Minion DHRII 3C EXO+ (29x2.4)
Derailleur, Rear SRAM GX Eagle, 12-Speed
Shift Lever SRAM GX Eagle, 12-Speed, MMX
Crankset SRAM Descendent 6K DUB (30t/170 mm), Boost Spacing
Bottom Bracket SRAM DUB 73 mm BSA Threaded
Chain SRAM GX Eagle 12-Speed
Cassette SRAM XG 1275 (10-52t) 12-Speed
Brake, Front TRP DH-R Evo 4-Piston, R1 2.3 x 203 mm Rotor
Brake, Rear TRP DH-R Evo 4-Piston, R1 2.3 x 203 mm Rotor
Brake Levers TRP DH-R Evo
Handlebar ANVL Mandrell 35 S (780x20) M/L/XL/XXL (780x35)
Stem RaceFace Aeffect R (40 mm)
Grips ODI Elite Flow
Headset FSA NO.57E
Seatpost OneUp Dropper Post & Remote, 31.6 mm
Saddle ANVL Forge Cromo
Pedals -
Extras Tubeless Valves & Sealant

Geometry & Sizing

Transition Sentinel Geometry
Sizes in MM S M L XL XXL
A: Stack 613 622 631 640 649
B: Reach 420 450 476 501 521
C: Head Tube
63.6° 63.6° 63.6° 63.6° 63.6°
D: Head Tube
100 110 120 130 140
E: Effective
Seat Tube Angle
78.2° 77.5° 76.9° 76.4° 76.0°
F: Seat Tube
350 390 430 460 490
G: Effective
Top Tube
552 585 613 641 665
H: BB Height 346 346 346 347 347
I: BB Drop 29 29 29 29 29
J: Chainstay Length 440 440 440 440 440
K: Wheelbase 1199 1233 1263 1292 1316
L: Standover 671 688 700 712 722
M: Fork Offset 44 44 44 44 44
Seatpost Diameter 31.6 31.6 31.6 31.6 31.6


Transition Bikes Sizing Chart