My Carrera Blast 24 rebuild

It’s going to be so much easier more expensive when they’re on 26’ers

Trust me

I can believe that, MoreCashThanDash 😀

Spent a quality 30 minutes last night with a beer and the Park blue book remembering how to adjust mechs. Now mostly shifting fine although I’m still not 100% happy with the upshift from 2 to 1. Had to play games as it’s a 7 speed shifter and cassette but a 9 speed mech, so the H screw needs to be really wound in. Future-proofed that bit of the drivechain though, so worth it.

So frustrating: just waiting on a delivery of a Shimano olive to shorten the front hose (LBS has been out of stock for a week and isn’t expecting more for another week at least), some rotor bolts, and the jig to saw the steerer down. Whilst I’ll hack the bottom off a seatpost in the vice by eye, I’m not going to do that for the steerer!

Waiting for the proper tool for the stearer wil be worth it in my experience. I made a mess of the first cut without it but with the tool it was perfect in a couple of minutes.

Either use a cutting guide or some decent pipe cutters for the steerer – both do an equally good job.

Measure, measure, measure, cut. Somehow still managed to cut the steerer 5mm shorter than I intended. Luckily I gave it an inch of spacers!

And apart from needing the cable clamp to arrive, the build is now finished.

Executive summary is: replaced the suspension fork with a carbon rigid fork, left it at 7-speed for now but dropped the triple front mech. Replaced almost everything apart from the seatpost, wheels, cassette. I have a pair of spare hubs and am learning to build wheels, so I can at some point go tubeless rims and 9-speed.

The cockpit is a resprayed Answer carbon bar, unbranded stem from eBay, Spank Grom grips, Deore levers, Altus shifter, Hope Head Doctor because that’s how much I hate star nuts (and for the splash of colour).

The forks are Carbon Cycles 24″ forks, with Deore brakes and skewers in an annoying almost-but-not-quite shade of anodised purple. Replacement wheels will happen at some point, so these are the stock wheels with Rocket Ron folding tyres. A whole kilo of bike was the stock tyres.

The foot end of the drivechain is Suntour XCT-JR 202 152mm cranks, with a RaceFace narrow-wide 32t chainring and matching bashguard, and Wellgo KC001 pedals. More on these later.

The wheel end of the drivechain is a Sora medium cage mech (trying to keep the cage as short as possible, and this will take a 32t cassette) with full outer cable routing, the stock 12-28 cassette (there’s a 12-32 on the workbench in case we need a bit more range), and another Deore brake. The Sora is a 9-speed mech so when the wheels are upgraded I just need a new cassette and shifter.

Saddle is a Madison Y04, the stock seatpost (a bit heavy and rusty so will be replaced at some point), and more anodised hotness from eBay for the clamp.

All in all the bike now weighs in a 10.1kg, down from 13.7kg originally. Obviously I’m now looking for a light carbon seatpost to knock that last 100g off!

So those Wellgo KC001 pedals are basically awesome, and it’s a terrible shame that Wellgo appear to have discontinued them. There’s a few resellers on eBay in China, the pair I got are genuine Wellgo in a proper box so I can’t comment on the relabelled ones. They’re a good size for kid feet, have studs but are not sharp, use cartridge bearings and look rebuildable, and weigh a svelte 135g each. The stock, huge, V8-style pedals the bike came with were 270g each.

Finally as tales of woe goes I thought “non-drive side crank thread shafted, LBS had to angle-grind it off” was the winner, but almost had a contender this afternoon when taking a rotor off my bike to donate it to the Blast. This happened to my T25 driver (last time I buy a Stanley tool because “what could go wrong”).

I had visions of having to drill out the bolt on my lovely Hope hubs, but luckily a competent Makita bit got the bolt off fine.

Likes!

The bike build rather than the knackered tools.

Someone is going to mention cost. I’ve been tracking part cost and weight, but haven’t dared to add it up yet.

It shouldn’t be too bad thanks to so many generous souls on here who had parts for sale. Thanks everyone!

Is it just the photo? The sweep of the handlebar seems to be forward rather than back?

Bike looks great, would have loved that as a kid.

Obviously I’m now looking for a light carbon seatpost to knock that last 100g off!

I don’t know about you but I don’t trust my kid with QR and carbon seatposts! Way too much chance of him over tightening..and crack!

We went Titanium … I think we paid £20+ post… as someone had cut it short it didn’t go for much on eBay 😀 and it was the right length for us so saved me cutting it.

Most cheaper carbon seatposts weigh more that a full Ti anyway as the weight isn’t in the tube but the (usually steel) clamps and bolts at the top…

Saddle is a Madison Y04

http://www.customriders.com/prodshow.asp?prodid=7764&gclid=Cj0KEQjwnsPGBRDo4c6RqK-Oqu8BEiQAwNviCRU3e6k5uD7MMiuO21SE9ivP_7vKIKmR6kOUlA25LMwaAl9T8P8HAQ

187 grams and £15 and the Kevlar really seems to work …. the fact it hasn’t torn in a year is amazing given the number of crashes…

Another hour before the boy got distracted and wanted to play on his iPad. Not quite the father and son build experience I was hoping for but what can you do.

It’s normal… or actually you did exceptionally. Most primary schools wouldn’t even TRY and keep a kids attention for a whole hour! (OH is a primary teacher)

If you want to keep a kids attention longer then you need to create an addiction to something, dopamine works great… which is exactly what game designers do… visual straight through to the reptilian brain and instant dopamine rewards… I say this as I was already worrying about my kids behaviour around the iPad… then I saw a video (not about kids but millennials in the workplace) and it all makes sense…

Sorry no answers except limiting use of iPad’s etc. but it’s worth watching

But on the original point…. been there and done it and that’s just their attention span – it feels disappointing but 1 hour is actually really good!

Regarding bars, Yeah that’s the angle of the photo with a wide lens. It’s a flat bar with a small backsweep.

Terrific finished article. Love the grips and pedals, might source some for LittleMissMC. Never occurred to me to respray those bars.

Don’t worry about kids and carbon seatpost, never had a problem with eldest yet, or younger one now. Maybe mine rarely bother to adjust them till I remind them. Or use a bolt up seat collar rather than a QR.

Don’t worry about kids and carbon seatpost, never had a problem with eldest yet, or younger one now. Maybe mine rarely bother to adjust them till I remind them. Or use a bolt up seat collar rather than a QR.

Mine adjusts his all the time…. its easy to get some grit in the QR so it becomes tighter etc. but quite a few times I’ve had to put more effort than I’d like in undoing the QR he’s hammered in with the flat of his palm…

In my experience carbon just goes – no warning…. (tightening a seatpost dropper trigger on the trails with a tiny allen key on the trail tool)

Not adjusting the seatpost isn’t a viable option for us… he’s flying off multiple dropoffs bigger than his wheels and his ability to shift back and forward and back again before the next jump of dropoff is crucial to not having a OTB incident.

One of his favourites is littered with helmet plastic and foam from numerous people who didn’t have their weight in the right place…

First ride! Okay it was up and down the road, but that’s a start.

The shock at having a bike he only just fits on instead of being obviously too large for was almost an early disaster. Giant cranks and long reach was quite a struggle. Had to lift the seat, fine tube the L screw (shifted fine in the garage but on a real hill, not so much), etc. Tempted to hunt around for a 30mm stem. But after a few minutes he was riding around and using the trigger shifters just fine (old bike had gripshift). He’s very happy with the Deore brakes, the modern levers work really well if you push them right in to the bars.

Hopefully this weekend a trip down to Bissoe or similar!

ace20 rims are about 410-420g and not particularly great either. they are quite narrow and soft alloy.

Not just soft, very soft!! My lads Hoy 24″ came with Ace20 rims and they have worn to the wear marker before he got through a pair of brake pads. So, does anybody have any ideas for a reasonable replacement rim or rear wheel???

Interested in the forks – where did you source them?
thanks
EV

El Vino, they’re from http://www.carboncycles.cc/?s=0&c=43&p=195.

800g with the full length alloy steerer, IS mount for the disk brakes.

Not just soft, very soft!! My lads Hoy 24″ came with Ace20 rims and they have worn to the wear marker before he got through a pair of brake pads. So, does anybody have any ideas for a reasonable replacement rim or rear wheel???

There’s lots of dirt jump/BMX rims but they’re incredibly heavy. Report back here if you find anything…

The best deal I’m aware of is the mk1 Stan’s Crest 24″ rims, available in the US for $43 each discounted (as they have the mk3 now). If you know someone going to the US shortly then order a load and bring them back to sell here! Postage is $70, which mostly destroys the discount: for an extra tenner you can get mk3 from a UK supplier.

Thanks Ross, Crests are a bit pricy, might go with one of these wheels, 1.3kg https://www.taylor-wheels.com/bike-wheels/24-inch-bike-wheel/taylor-wheels-24inch-bike-rear-wheel-double-wall-rim-7-10-cassette-black-silver

Those aren’t disc wheels..

Those aren’t disc wheels..

Well spotted, the bike doesn’t have disc brakes and I wasn’t going to upgrade….

Bump this fine thread to ask how one drills out the cable stops? Is it just a case of using a long drill bit and sort of angle it in there? They’re obv right on the frame so doesn’t seem to be much space for the drill.

Bump this fine thread to ask how one drills out the cable stops? Is it just a case of using a long drill bit and sort of angle it in there? They’re obv right on the frame so doesn’t seem to be much space for the drill.

That’s what I did on the kids Cannondale frame but its a bit hit and miss but more as it breaks through the very thin “stop”…. It would probably be better to use a small file or dremmel but I got away with it then cleaned it up with a needle file

I was too lazy to buy a long bit and used a standard 4mm bit then a 6mm to carefully nibble away at the narrow end of each stop. Good spray of WD40 on the bit to keep it smooth and a file to clean it up.

Thanks – I’ll give it a go.
Have our kid’s done now with the exception of the rear brake hose being zip-tied round the top tube, plus horrible forks are still in situ.

Rather than drilling, I used some of these that clamp into the cable stops. They work great.

https://www.evanscycles.com/m-part-hose-guide-set-00120605?esvt=55224-GOUKE2389278&esvq=&esvadt=999999-0-1222684-1&esvcrea=189745168282&esvplace=&esvd=m&esvtg=pla-263103918233&esvo=00120605-NA-NA&esvaid=50080&gclid=CjwKEAjw2qzHBRChloWxgoXDpyASJAB01Io0RtjuzpUX22aaIGyzcgrY9_ueEPn74Zdvkfb9aoCCRRoC_efw_wcB

You can see one in this photo.

ads678: what mudguards are those and do they work?

Does anyone know what internal/external size the seat tube is on a 24″ Blast, please? Thanks.

Mine is a 27.2 internal, 31.8 external.

Found it! 27.2 seatpost and 31.8 clamp for anyone else that needs it.

(Beat me to it by 15sec! Thanks Ross).

Well spotted, the bike doesn’t have disc brakes and I wasn’t going to upgrade….

Given its disk ready why not ???
For me the biggest plus of changing to disks initially was….
1) Wheels go on and off without having to release the cable
2) Wheels don’t need to be trued to within 1mm every ride to prevent rubbing and still work

A year on and they are being used for the stopping power but that wasn’t why I initially ditched the v-brakes.

ads678: what mudguards are those and do they work?

Ross, sorry missed this. It’s one of these http://www.chainreactioncycles.com/zefal-no-mud-universal-mudguard/rp-prod143861 and yes they work pretty well.

I had one on my 26″ mtb as well, it’s for a 26″ wheel but seem to fit quite well with 24’s as well.

Just bought my eldest a Blast 24, and middle boy a Blast 20. Going to be stripping some weight off the 24 ASAP and this thread has given me some good ideas 🙂

Forks are crap, so going to stick a pair of 700c disk forks on it for now (a-c not far off the original sus forks). Got some shimano hydros knocking around so may chuck them on too.

I’d like to go 1x at the front, does the original crankset allow mounting of “standard” 104bcd chainrings? The BCD looks to be 104 but the mounting bolts/holes look odd.

Anybody have an answer to chainring question?
I’m about to start the same weight loss program with my youngest son’s handed down Blast 24 and losing the rusty triple set up is first on the list for the bin 🙂

Mine is an older model Blast and the chainrings were rivetted on, so you probably need a new chainset to go 1x unless they’ve changed it. The Suntour Junior XCT is a good option. Cheap and square taper with removable chainrings.

https://www.amazon.co.uk/d/Sports-Outdoors/Kettenradgarnitur-SR-Suntour-T20242-Z%C3%A4hne-schwarz/B0029MP3AO

As above, on closer inspection the rings are rivetted on. I’ve bought one of those chainsets Rickos has posted – £24 inc postage, bargain. Hoping I can re-use the existing BB mind as that seems nice and smooth.

Here’s mine – changed the forks & tyres and put his old saddle and post back on as they fit his backside better 🙂