Nomad Mk3 confusion?

[kwkirby01]

I've been looking at the new Nomad Mk3 brochures (not that I can afford a new bike just now, but there's no harm in looking!)

The NOMAD Mk3 ROHLOFF 650b brochure states:

With 650b wheels there is only the option of having disc brakes front and rear, using the Thorn Mk3 Steel disc fork, which takes a 110 x 15mm BOOST through axle.

However, the THORN NOMAD Mk3 AB Special clearly shows a picture of a 700c Nomad with V-brake forks and reversible brake bosses, suggesting that it would indeed be possible to have a Nomad with a front V-brake and 650B wheels.

Is there a technical reason why this wouldn't work?

Kevin

[spoof]

Hi Kevin,

The Nomad MK3 AB Special uses a different model of fork, same as the Mercury 853 V-brake fork. The forks in the brochure for the 26" and 650B Nomad MK3 models are different and sold as either v-brake only, or disc only 'thru-axle' choice I believe. A quick look at the MK3 26 inch model forks for v-brake only on their website (link below) they do advertise reversible v-brake bosses for 26" and 650B compatibility so my thoughts are you can run v-brakes with 650B with suitable 650B rims and adhere to the max tyre width for a build.

I think this is right, hope it helps.

Kyle

Fork link https://www.sjscycles.co.uk/forks/48-offset-a-650b-26-inch-thorn-nomad-mk3-steel-fork-gunmetal-imron/

[kwkirby01]

Thanks Kyle, similarly, these forks are v-brake and stated as 650B/700C and Nomad compatible:

https://www.sjscycles.co.uk/forks/46-700c-650b-thorn-mer853vc-steel-fork-gunmetal-imron/

Either way, it's not clear why a Nomad Mk3 650B should be front and rear disc brakes only.

[PH]

Does seem a little odd for them to be selling a 650B rim brake fork and saying the complete bike is disc only, there might be an obvious answer but it hasn't occurred to me.
The 700c AB brochure also has an oddity, the fork on the pictured bike isn't the one in the description, maybe they were experimenting.
So - Even though you're just looking, which would you go for?

[kwkirby01]

Given the way I cycle, I know my current front v-brake will support an effective emergency stop in all conditions I would choose to cycle in, so I don't need a front disc brake.

If v-brakes are adequate, perhaps it be easier to have them front and rear (the Nomad frame supports this – see the 26” Nomad in the latest mega brochure, which looks a lot like my current Sherpa).

That said, the disc fork can handle larger tyres to match the rest of the Nomad frame, but do I need tyres which are bigger than the 50mm supported by a v-brake fork? Would an extra 10mm (i.e. 60mm tyres) add significantly to comfort?

The disc fork looks purposeful and seems to suit the Nomad, but the simple, straightforward lines of the 853 fork appeal too.

In answer to your question PH, I'm not really sure!

[PH]

Given the way I cycle, I know my current front v-brake will support an effective emergency stop in all conditions I would choose to cycle in, so I don't need a front disc brake.

I don't need disc brakes either, so with my Mercury I went for the 853 V brake fork and a cable disc on the rear. I have no issues with that, it's a lovely bike.
BUT
Having since got a work bike with hydraulic disc brakes, it's what I would have chosen now.  The much talked about comfort difference is lost on me, with the same 35mm tyres I can't tell the difference.  They win when it comes to ease of maintenance and lack of adjustment.  And although I've always stopped fine with V's (Or cantis or calipers) there is something nice about just needing a gentle squeeze to do so.
The argument about repairability in the field is as relevant as ever, or not if it doesn't apply to your usage.

[spoof]

Hi Kevin,

The v-brake nomad forks linked to previously support tyre widths beyond 50mm so they will be more than fine if you want to change tyres and go slightly wider, though like mine during removing and replacing, the tyre has to be mostly deflated to get the tyre past the brake blocks. The forks support tyres widths of 26 x 2.35" (60-559) and 60B x 650B (60-584) tyres and that is said to be the maximum using mudguards applied to fork. Removing the mudguard maybe the fork will run even wide tyres likely. I do get confused all the time with tyre measurements etc but in metric terms all around 60mm wide for either size tyre/rims I believe.

There is a short but great write up on page 44 of the Thorn Mega Brochure by Andy Blance who experimented and compared heavy duty forks running the disk brake vs the v-brake for comfort etc. His findings are very interesting indeed. After reading it, I think that maybe led onto Thorn deciding to increase the axle width for their disk brake fork option to 15mm thru axle possibly? The wider axle I presume is stronger, more rigid etc. A benefit I read about the thru axle is that they help align the disk rotor near identically between the brake pads when removing / reinserting a wheel eliminating any variance that can cause rotor rub on the pads.

Thorn Mega Brochure here: http://www.sjscycles.com/thornpdf/thorn_mega_brochure.pdf

Kyle

[Pavel]

Does seem a little odd for them to be selling a 650B rim brake fork and saying the complete bike is disc only, there might be an obvious answer but it hasn't occurred to me.
The 700c AB brochure also has an oddity, the fork on the pictured bike isn't the one in the description, maybe they were experimenting.
So - Even though you're just looking, which would you go for?

Perhaps there now is one or two, but thus far I've never seen a 650B rim that was meant for V-brakes, so perhaps the lack of rims is why 650B is considered disk only?

[PH]

Does seem a little odd for them to be selling a 650B rim brake fork and saying the complete bike is disc only, there might be an obvious answer but it hasn't occurred to me.
The 700c AB brochure also has an oddity, the fork on the pictured bike isn't the one in the description, maybe they were experimenting.
So - Even though you're just looking, which would you go for?

Perhaps there now is one or two, but thus far I've never seen a 650B rim that was meant for V-brakes, so perhaps the lack of rims is why 650B is considered disk only?

Good point and not one I'd considered - So I looked at what SJS stock and although most are disc, 6 of the 36 650B rims are suitable for rim brakes
https://www.sjscycles.co.uk/rims-650b-275-584/?type=rim+brake

[mickeg]

650b wheels were used for decades before disc brakes were created. 

[Robin Thorn]

Good morning people.
Thorn Cycles bike production workshop and sales staff all finished yesterday. To preserve the company for the future all staff have been furloughed. One person (Cath) remains active there to deal with outstanding issues relating to ongoing builds. THERE WILL BE NO TECHNICAL SUPPORT until we resume.
SJSCycles remains open for mail order sales from our website, telephone orders and tech enquiries can still be sent but there may be some delay.
Before Andy finished yesterday, he wrote this reply... please excuse me, we are very over worked here with our remaing staff, I've not had time to re-read the rest of these posts, I hope Andy's explanation helps:

Hi Kevin,
Thanks for the enquiry. Yes, technically you could use one of the 650b/700c forks - either the ST or MER version. However what rims would you use?
Our Thorn 650b rim brake rims are only really suitable for lightweight touring, as stated on page 39 of the Bike Bible. If you wanted such a bike, it is likely that a Mercury Mk3 or Club Tour Mk5 would serve you better.
Ryde make an Andra 40 rim, which is a rim brake rim but this is significantly heavier than an Andra 30 and obviously 650b rims are heavier than 26” rims - so we decided that, whilst possible - it’s not a sensible option. 26” wheels with Andra 30 would be far superior. I think that Andra 40 and our 650/700 forks would be a miss match.
There are some other 650b rim brake rims on the market but the ones that I’ve seen really are old fashioned rims from the 1950’s/60’s, made from low grade alloy, in a design that can’t take pressure and which are being sold at extortionate prices.

Yes you could use one of our 650/700c forks with a Nomad Mk3 frame and run 650b rims with rim brakes F and R.

I hope that this helps.
Best regards,
Andy B.
Sent from my iPad