Scout 275 Custom build

Monday, April 20th, 2020

“Custom Build Scout 275”

With the current situation most of us are fortunate enough to be spending a little more time indoors and tinkering with bikes recently. Nukeproof staff are no different, currently the main office staff are all working from home.

With time indoors this weekend, marketing manager Rob treated himself to a new Scout 275 frame. The donor bike was a 2019 Mega 275c for the build kit, with a few of our latest components to freshen things up.  As part of the build I’ve tried to show a little “average mans” guide to fitting a new Horizon headset and Bottom Bracket. Most that know me will account for the fact that I am no mechanic, but thought it was a good chance to teach myself and “give it a go”. 

Un-boxing the new 2020 Scout frame, the frame comes packed with a small parts box, so don’t loose that as it has some guides, parts and spares you need, plus a little tub of touch up paint should you need it. The frame comes ready fitted with the upper and lower bearing cups for a headset. However since I wanted to swap the stock headset for Horizon Ti headset (Red) the first job was to remove the cups. 

Nukeproof Headsets are sold as separate top and bottom cups, so for a Scout (and most Nukeproof’s) You need a ZS 44-28.6 (Nukeproof Part Number T2) top cup and  ZS 56-40 – (Nukeproof part Number: B8). 

First thing I generally do is clean and grease the headtube internal top and bottom.  

I then applied a thin layer of grease to the headset cups. Fitting the cups only (ensure all bearings are removed, so press in the empty cup only). Using a headset press line up the top and bottom cups and wind into place (I used a Brand-X headset press). In the past I have used a wood block and a persuading hammer- but this is a much easier and cleaner way!  

With the cups in place you can now layer in the bearings, dust seals and top cap. 

Prior to inserting the fork into the frame you need to ensure/ fit the crown race on the base of the fork.  Again I’ve applied a layer of grease to keep things smooth and stop water penetrating in the future. (maybe applied too much geese but sure some will seep out over time).  

With the fork inserted, layer up you Headset, top cap, top cover then head set spacers and stem to suit (ensureing there is a gap of 2mm between the top of the steerer and the top cap.  Tighten the top cap with 5mm allen key to pull the headset together. Don’t over tighten it, just until you feel there is no play in the headset in the frame (Note. As i am using a donor bike and swap across from another bike I’ve left the fork steerer a little longer). 

Next up to fit to the Scout was the new Horizon BSA 73mm Ti Bottom bracket (BB) GXP.

I was swapping a set of 2017 Sram X01 cranks from my Mega 275c (they have been on a number of bikes now!), so I needed a GXP version of the Horizon BB. 

Again, prior to fitting apply grease to the threads and thread of the frame BB. Initially I tried to space the cranks a little wider using the BB spacer (came with the BB). However, when I fitted the cranks, I decided to removed these as they were unneeded.   

Carefully initially thread the BB by hand and then tightern using a BB tool. Torque the bottom bracket up to between 36-50NM. Note the thread direction printed on the BB’s as they don’t thread “normally!”. 

Once both sides are fitted insert your Crank, Note that on the drive side will need the “wave washer” on the shaft between the chain ring and the BB. Tighten the Crank as normal.  

Ideally, I should have fitted the Chain guide prior to inserting the crank, but it was pretty simple to work around the chain ring to it to the ISCG-05 mounts on the Scout. You Need to loosen the top guide to clear the chain ring, then fit to the ISCG05 tabs on the frame with the spacers provided. On the Scout I used a thick 3mm and thin 1mm washer to align the chain in the centre of the chain guide. Ten adjusted to the correct position and tightened in place.   

From there it’s pretty straightforward to piece the frame together. Sram have some good online tutorials to set up their drive trains. The shifter and brake cables run neatly under the top tube externally (using the mounts and zip ties provided in the small parts box). This Scout received my  “third or fourth hand drivetrain”. However it was serviced recently, but made up of a mix of Sram X0 and GX Eagle parts.  


The Only “tricky” fitment on the scout is to run the internal cable routing for the dropper post. However with the large open ports, its actually a pretty simple job. Just don’t forget to fit the supplied cable guide grommets to guide and hold the cable neatly. The dropper routes down the seat tube out and under the BB then back into the Downtube and out the right hand side.

Again I was running Rockshox Reverb and brakes from my XL Mega which is slightly longer than the Scout, so the cables we’re longer than ideal, which I chose to leave, just in case I swap this build kit again! As the mega was internally routed I just needed to do a quick leaver bleed to re pressurise the system and remove any air. Plus I refreshed the brake pads with a set of Nukeproof Code Sintered pads

The rest of the finishing kit was a mix of new and old Nukerproof components. I bought a few little upgrades just to tidy up the bike, treatign it to new Horizon V2 Carbon bars & a fresh Sam Hill Grips.

XL Scout 275, “Grinch spec”

Full Spec List: 

These cranks have seen a few miles, think this is their 4th build now

Evidence of the last time the old bike was used 

New V”2 Carbon bar and Grips freshen up the cockpit 

Something old, something new, I may change the tyres for some faster rolling rubber for more a more ‘XC spec’, I think I have a Michelin Force in the garage.

Looking forward to the right time now to enjoy the local trails, until then It will do as an exercise machine.

Follow us @nukeproofbikes for the latest goings on 

Photo: @RobSherratt21 Phone shots 

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