putting a road disc wheelset on a mountain bike

harringtonp

My mountain bike is well battered and I am half thinking of getting the Boardman Mountain Bike Pro 29er from halfords

http://www.halfords.ie/webapp/wcs/stores/servlet/ProductMobileDisplay?catalogId=15551&categoryId=212589&langId=-1&productId=1173726&storeId=11101

I'm trying to figure if I could buy and fit a road disc wheelset to it and use it as a winter road bike on club spins etc. From what I can decipher, specs wise the bike's rear hub is a
12x142mm through axle and this seems to be becoming a de facto standard for rear road disc wheels. The fork on this bike is described as "RockShox Reba RLT air fork with 120mm travel and through axle" . Assuming this is

https://www.evanscycles.com/en-ie/rockshox-reba-rl-solo-air-29-fork-EV316868

then the axle is 15x100mm. From reading I gather that most road disc fronts are going towards 12x100mm.

So are there many road disc wheelsets that fit the 12x142 read and 15x100 front dimensions ?

Or are there adapters to convert 15x100 to 12x100 ?

Can anybody send a link to a good quality road disc wheelset that they feel would fit ?

And are disc rotors something to be concerned with at this stage or is it just a case that you fit whatever rotor on a disc wheel and the brakes can be adjusted to take it ?

C3PO

Why not fit road tyres to the wheelset supplied on the Boardman?
I've no idea about the pace of your club spins (or you ability) but trying to keep up on ours with a heavy mountain bike and suspension forks would be a complete nightmare!

harringtonp

I went out on club spins with an old mountain bike on slick tyres a few times 2 years ago. The spins went from being very easy to hard but manageable. And there is always a slower group to drop back to.

Changing tyres can be a hassle if you are using it mountain biking one week and on a club road spin the next. Hence the extra set of wheels.

Ideally I'd be looking for a good light set of wheels which could take a tyre as thin as a 25mm or 28mm and as wide as what guys use for CX. If I were to get a Road or CX disc wheel bike in the future I'd want the wheels to work with them.

C3PO

Well I know for sure that one of clubmates used the 29er wheels from his mtb on his CX bike so they would seem to be interchangeable as long as you get axle width etc correct. Still think it might be easier (safer!) to buy a light set of mtb wheels and use them with 28c tyres!

harringtonp

What I am partly getting at is that in an ideal standardised world there should be no such thing as wheels for 29ers, wheels for CX and wheels for road when it comes to discs. They're just wheels that take discs.

If they all take a rim diameter of ISO 622mm and are all disc then it should be a case that if you invest in a good set of wheels for a road bike, they will also fit a CX bike and a 29er. The only thing preventing this from what I see is standardisation. I'm just trying to figure out what mountain bike to get so that if I do get a disc road or CX bike in future I can swap wheels.

This is how it is with road bikes using rim brakes. Apart from edge cases, if you have a good set of wheels you can use them on any new road bike that you buy. In general you don't have to worry about it. Just buy the new bike and fit the good wheels.

Lumen

harringtonp wrote: »

What I am partly getting at is that in an ideal standardised world there should be no such thing as wheels for 29ers, wheels for CX and wheels for road when it comes to discs. They're just wheels that take discs.

Rim width is important for tyre shape.

35mm tyres are really marginal on a traditional road rim (I know this from CX before the current trend of wide road rims started).

I'm not sure I'd want to run a MTB tyre on a road rim, and vice versa, even before considerations of tubeless vs beaded tyres.

C3PO

That's the point I'm making - as far as I know 29er wheels are interchangeable between bikes as long as the axle dimensions, and wheel rim width are the same!

ford2600

Lumen wrote: »

Rim width is important for tyre shape.

35mm tyres are really marginal on a traditional road rim (I know this from CX before the current trend of wide road rims started).

I'm not sure I'd want to run a MTB tyre on a road rim, and vice versa, even before considerations of tubeless vs beaded tyres.

14mm internal would mean a max tyre of 28-30.
After that it's pinch flat central unless you run at pressure that make it pointless anyhow.

Although a modern road rim with internal 19mm or so would handle 35mm just fine

I would have thought that you might want to consider rotor diameter also?

It's in the manufacturers interest that you can't do sh1t like this.

Unless you ride technical stuff by a cx bike and use as winter bike and for off road?

harringtonp

C3PO wrote: »

That's the point I'm making - as far as I know 29er wheels are interchangeable between bikes as long as the axle dimensions, and wheel rim width are the same!

Does anybody have experience of and can verify this ?

Even if axle dimensions are a bit different are there adapters (read somewhere mavic supply them with some of their disc wheels), anybody experience of this ?

harringtonp

ford2600 wrote: »

Although a modern road rim with internal 19mm or so would handle 35mm just fine

I would have thought that you might want to consider rotor diameter also?

It's in the manufacturers interest that you can't do sh1t like this.

Unless you ride technical stuff by a cx bike and use as winter bike and for off road?

A modern disc road rim with 19mm internal width is a good example.

If you invested in an expensive set of 19mm carbon disc wheels some future proofing would be nice. You would like to think you could run them with 25mm or 28mm tyres on a road bike, 25mm-35mm on a cx bike (25mm if using it as a winter road bike) and 35mm+ on a mountain bike. Basically if you owned all 3 types of bikes and had an expensive wheelset you would like the option of been able to use it on all 3 by switching tyre.

So question is does anybody have any experience of this ?

I know very little about rotor's, is diameter an issue ? I presume the brake can be moved up and down the frame the way a front derailleur can be repositioned when switching from compact to standard cassette ???

Lumen

harringtonp wrote: »

35mm+ on a mountain bike

Except MTB is more like 50mm+

It's a lot to ask of a rim to properly support both 25mm and 50mm tyres, so you'll inevitably end up with a compromise, and then why are you buying fancy expensive wheels which offer only marginal improvements?

i.e. arguably two sets of cheaper rims with appropriate widths for their tyres will outperform one set of expensive rims.

Not to mention the hassle of changing tyres and rotors every time you switch bikes.

And then the fact that you would presumably want to run tubeless on the MTB which is going to introduce a load of gunk and hassle into switching.

harringtonp

Lumen wrote: »

Except MTB is more like 50mm+

It's a lot to ask of a rim to properly support both 25mm and 50mm tyres, so you'll inevitably end up with a compromise, and then why are you buying fancy expensive wheels which offer only marginal improvements?

i.e. arguably two sets of cheaper rims with appropriate widths for their tyres will outperform one set of expensive rims.

Not to mention the hassle of changing tyres and rotors every time you switch bikes.

And then the fact that you would presumably want to run tubeless on the MTB which is going to introduce a load of gunk and hassle into switching.

Except not talking about every time changing. Talking about a mountain bike where you have the mountain bike wheels it came with on it which you use mountain biking at the weekend and then during the week for whatever reason you want to switch a fast pair of road wheels onto it before switching back to your mountain bike wheels the following week.

Its not really tyres I'm talking about, its more being about been able to move the wheel easily from bike to bike.

I have a race bike and a winter/training road bike. I've good carbon race wheels, alu race wheels and heavier winter wheels. The tyres may not be suitable for what I want but I can at least quickly put any of the 3 sets of wheels on either bike because as far as the wheels are concerned the bikes are the same.

If I owned mountain, cx and road bikes with disc wheels I'd want the same: be able to switch them easily and this is what the thread was originally about. I was hoping somebody who is familiar will all 3 would say "buy bikes with these axle dimensions and here are links to some wheelsets which should fit them."

harringtonp

From a mountain bike friend of mine

----


"It's tough in MTB. They change every year or so.

Front hub widths have been 100mm for ages but the rear hubs were 135, 142 or 150mm depending on intended purpose I.e. XC, AM/Enduro or ST

As Enduro boomed 142mm seemed prevalent

And then fat bikes inspired plus size tyres and in order to get the correct tyre clearance the Boost standard of 110mm and 148mm front and rear came along.

This was a way of running 27.5+ wheels on 29er frame and fork

My old 2016 29er frame broke last year. It was 142mm hub compatible. I got a 2017 frame as replacement and it took Boost.

This was a major pisser as I had only bought a brand new wheelset the previous month which was 142mm

Long story short I must have spent about 350euro on a brand new rear Boost hub, new longer spokes, adapters and a **** load of time relacing the wheels.

My 26er hardtail is superb but wouldn't be worth selling for the price I'd get for it. It's hard to find anyone stocking decent 26er tyres anymore.

Good luck with futureproofing in MTG!"

harringtonp

Hopefully the road scene will avoid this trap

https://www.youtube.com/watch?v=Jj0uBQ7j5c4&feature=youtu.be