Viewing 40 posts - 1 through 40 (of 49 total)
  • Monstercrosser conversion
  • Premier Icon gs_triumph
    Free Member

    Good morning,

    I am looking to turn my hardtail into a monstercross of some sort. Intended use would be winter gravel rides, pentland hills plus rare trips to blue and maybe some red trails.
    Its a 2015 radon Team ZR with XT/SLX 3×10 11-36 drive train and reba fork.
    Looking to put drop bars on it with brifters.

    I measured the reach and stack (i think 🤔) at 42cm reach and 72cm stack. Which is reasonably comparable with my gravel bike that is 38cm reach and 71cm stack. I think the reach could be resolved with shorter stem and a the narrower drop bar.

    So, the plan is…
    Radon Team ZR Frame, keep fork with intention to replace with a rigid at some point.
    GRX 400 brifters
    Tiagra FD & FSA 50/34 crankset
    Tiagra RD with existing 11-36 cassette
    Replace 100mm stem with 60mm and use a 420mm drop bar i have in the shed.

    Am I missing something?

    I believe the tiagra mech will stretch to a 36 cassette as is well reported on the web.

    I am aware the crankset may clash with the chainstay. It is coming off the gravel bike so I could try it for fit.
    Would a GRX 2×10 crankset work better?

    Some of the bits will be new, some parts bin or will be taken off my gravel bike (being upgraded)

    Any advice would be welcomed. I guess the crankset/fd is the biggest area of concern.

    Thanks,

    Premier Icon Paul-B
    Full Member

    What’s the advantage of doing this over just riding the gravel bike you already have?

    Not trying to be a smart a$$ just genuinely interested as someone who’s been hovering between buying a gravel bike and doing a drop bar conversion on an old hardtail

    Premier Icon joshvegas
    Free Member

    Yep I don’t see the point.

    My gravel bike will go around glentress quite happily. All you will be doing is making the hardtail less different and removing options.

    Premier Icon montgomery
    Free Member

    What are you doing brake caliper wise? Post-IS-flat mount considerations, future proofing.

    Premier Icon Dickyboy
    Full Member

    What’s the advantage of doing this over just riding the gravel bike you already have?

    For me it’s being able to fit 2.4″ tyres for increased comfort & grip

    Premier Icon joshvegas
    Free Member

    For me it’s being able to fit 2.4″ tyres for increased comfort & grip

    But would you sacrifice a mountain bike to get it if you already have a gravel bike?

    Premier Icon gs_triumph
    Free Member

    The MTB is not really being used. Has been out of the shed twice in the last year.
    It will be getting used mainly as a winter bike and when bigger tyres are required, mainly for muddy conditions.
    I can get this up and running for a few hundred pounds, if that, versus the price of a new or second hand bike.
    And it might just be entertaining to do. 😃
    I accept the gravel bike will go most places, including glenrress and the oentlands. It already has. But it does have its limits without putting silly tyres that hamper its on road performance.
    Keeping the original hydraulic calipers.

    Premier Icon joshvegas
    Free Member

    Fair enough 🙂

    I think you will regret 42cm bars though if you want to go rougher.

    Also I dunno if road brake levers play nicely with mountain bike calliper you’d have to check that.

    Premier Icon gs_triumph
    Free Member

    I’ve got the grx levers set up with rs785 calipers just now.
    I believe shimano simply rebadge a lot of calipers accordingly.

    Premier Icon gs_triumph
    Free Member

    I’d replace the bar witha ritchey venture max in the near future.

    Premier Icon gs_triumph
    Free Member

    Anyone got any knowledge of fitting road cranks to mtb frames?

    Premier Icon john_l
    Free Member

    Chainstay clearance (rings and cranks) might be an issue. Used to be ok with sq taper as you could just use a longer axle, HT bbs are obviously more restrictive.

    Premier Icon gs_triumph
    Free Member

    @Dickyboy what did you regards crankset?

    Premier Icon Dickyboy
    Full Member

    what did you regards crankset?

    Used an XT double crankset with 40/28 rings, didn’t venture into road stuff I’m afraid.

    @josh – I already have two hardtails & heavy steel tourer/gravel bike and wanted something lightweight for a bit of fun bridleway exploring

    Premier Icon gs_triumph
    Free Member

    @dickboy What front detraileur? And shifters?

    Premier Icon joshvegas
    Free Member

    @josh – I already have two hardtails & heavy steel tourer/gravel bike and wanted something lightweight for a bit of fun bridleway exploring

    Don’t get me wrong I totally get it, i keep looking at an old genesis io frame and thinking singlespeed monstercross to compliment all my other bikes. I’m just not hugely convinced if the OP has two bikes (a total ssumption) that making one cobbled together one inbetween will be that satisfying compared to say putting some 650b wheels on the gravel with thicker wheels or chucking some swept bars and a rigid fork on the mountainbike and having two bikes with a bit of overlap.

    Premier Icon hardtailonly
    Full Member

    I did this to a Genesis Fortitude frameset. The road crankset snagged on the chainstay so I needed to run a MTB crank.

    I found it too long as a drop bar bike, and therefore a bit ponderous and unwieldy, but it sounds as though you’ve measured and it might be fine for you.

    I was running mine Singlespeed, I enjoyed it, but as I also have a nice gravel bike, and 2 other hardtails, there was quite a lot of overlap with the other bikes I’d got, and it was neither light and agile like my gravel bike, nor more off-road capable like my MTBs, so ended up not being the bike I wanted/needed.

    I’d still consider a Monster-cross build in the future, but would need to think carefully about how to execute it well.

    Premier Icon honourablegeorge
    Free Member

    gs_triumph

    I accept the gravel bike will go most places, including glenrress and the oentlands. It already has. But it does have its limits without putting silly tyres that hamper its on road performance.

    Pretty sure dismantling the gravel bike to build a monstercross will hamper the on road performance even more

    Sounds to me like what you ctually want is a second set of wheels for the gravel bike.

    Premier Icon Dickyboy
    Full Member

    What front detraileur? And shifters?

    Odly enough tiagra triple sti & deore double mech 🤔

    Premier Icon smiffy
    Free Member

    Also I dunno if road brake levers play nicely with mountain bike calliper you’d have to check that.

    No problems at all, either way round. I have both.

    Premier Icon gs_triumph
    Free Member

    I have only the two bikes.
    The gravel bike, i have riden pretty much exclusively since I got it. The MTB has sat in the shed.
    I now find find since the weather has turned there are places I would like to go on the gravel bike but can’t due to mud and general trail conditions. I take the mTb out and just don’t enjoy riding it as much as I used to. I want the flexibility the drops give me. I am also getting older and don’t go to trail centres anywhere near as often as I did even 5 years ago. I am enjoying a different kind of riding.
    …and let’s face it. None of the changes I am proposing are irreversible.
    I have 40c on the gravel bike just now, have had 42c in the past and could maybe squeeze a 45c. I don’t see there is enough space even with 650b to go much bigger. I doubt a 2″ tyre would fit with any kind of mud clearance and part of the reason for wanting to do this is to allow me to venture to muddier places than the gravel will allow during the winter.

    Its a less well thought of frame manufacturer, so I wouldn’t get much selling it. To buy a gravel bike designed for bigger tyres would cost me more than I’m prepared to spend by a long way – into the 000’s
    I figure for a few hundred pounds I can get to what I want and have a bit of fun figuring it out in the mean time.
    If its a pile of poo I can always put it all back to how it was before and I have a few more bits for the next project.

    Premier Icon Wookster
    Full Member

    What set up you running? I’d like to run GRX levers with XT would that work do you think?

    Premier Icon gs_triumph
    Free Member

    You should be able to get grx lever working with an XT rear mech with a wolf tooth tan pan.
    The front is a different story all together… I am finding 😃

    Premier Icon legometeorology
    Free Member

    Sorry to be another that comes in and doesn’t answer the question you asked, but unless you’ve done so already, I’d seriously consider looking into changing to some alternative bars (like Jones/On-One Mary’s, etc.) and getting some decent rigid forks

    Those two changes together would make a massive difference, and could get you back riding that bike. Moving to drops may do the same, but if you still run the Reba’s the bike probably won’t feel much faster, and it’s not cheap — the money spent on brifters, etc. could get some really nice rigid forks

    Premier Icon legometeorology
    Free Member

    (I’m saying this as someone that has played around a lot in that space between gravel bike and 29er)

    Premier Icon gs_triumph
    Free Member

    @legometeorology
    Thats not a avenue I had even considered.
    I will start looking into that

    Thanks

    Premier Icon joshvegas
    Free Member

    If you do fancy giving it a go. I have a set of marybars you are welcome to try out if you’re shooting past Peebles.

    When we are allowed out to play obviously.

    Premier Icon gs_triumph
    Free Member

    Thanks @joshvegas that’s very kind of you 😄👍

    I’ll do a little digging later on and see whats what.

    Cheers guys.

    Premier Icon gs_triumph
    Free Member

    Wow… there’s a whole world a
    Of “Alt” bars I didn’t know about 😄

    Premier Icon montgomery
    Free Member

    I’ve been running Mary and, more recently, Geoff and OG bars since 2007. I like them a lot, but the position and ride is very different to the drops (from an old CAAD8) I now have on the same frame as a monstercross conversion.

    Mary:

    Geoff:

    Drops:

    Premier Icon gs_triumph
    Free Member

    @montgomery Looks good! How do you find the Geoff bar?
    I’m looking cinelli double trouble as well. All jones copies I guess but I can’t mentally drop £100 on a handle bar!

    Premier Icon gs_triumph
    Free Member

    Are there more positions to be had with he loop style double bar types over the single swept bars?
    Or is the extra bar used mainly for bar bags and lights/GPS etc?

    Premier Icon gs_triumph
    Free Member

    Next question…
    Any recomendations for a tapered suspension corrected rigid 29er QR fork?
    (See… I have been paying attention 😉)

    Premier Icon montgomery
    Free Member

    I used the loop to get forward on long, non-tech climbs, and slogging into headwinds, but it also made mounting lights easier when I had a bag strapped under the bars.

    I’ll use them again, but I’ve liked the cobbled together monstercross over the last 10 months so I’m now throwing some money at it for a Spring rebuild, based on these bars:

    I think this kind of thing can work with old MTB frames that were designed around shorter reach/longer stems. I’m not sure how well a conversion based on a modern, longer frame would go.

    Premier Icon cp
    Full Member

    tapered suspension corrected rigid 29er QR fork?

    Look up exotic carbon forks. Aim for 465mm or 490mm axle-crown length.

    You can use a straight steerer one too, you just need a crown race adaptor (cheap and widely available on eBay).

    Premier Icon docrobster
    Free Member

    I’ve done something very similar to this recently. A 2014 pinnacle ramin. geometry pretty similar. Rides ok. I’ve got 36c tyres on it. On one midge bars. Still got the xc30 fork but looking to replace with one of those exotic carbon bars someone mentioned.
    Only thing you may need to consider is bb shell width. If it’s 73mm you’ll not be able to use your road cranks. I had to use some old mtb cranks but with 32-44 rings on the front and 11-36 cassette the gearing is about right.
    I’ve got cable discs as I had mechanical brifters in the shed. They work fine. It’s 2×9 with tiagra shifters and deore mechs. Got 105 calipers. 55mm stem

    https://www.instagram.com/p/CHs7PBUnsjP/?igshid=92b2opad5q00

    Premier Icon docrobster
    Free Member

    Next question…
    Any recomendations for a tapered suspension corrected rigid 29er QR fork?

    I’ve just ordered these:
    eXotic Rigid Carbon 29er Mountain Bike Fork, Post Mount PM Disc Brake, 49.0cm 29 https://www.amazon.co.uk/dp/B01AMNB6ES/ref=cm_sw_r_cp_api_fabc_ApYaGbP32VECK?_encoding=UTF8&psc=1

    I’ve got a 44mm headtube and suitable zs lower cup so went for straight steerer. My wheel is quick release. Tapered bolt through versions available for around £135

    Premier Icon gs_triumph
    Free Member

    I’d like to thank everyone for their input up to now.

    Thanks to you guys I’m in a bit of a quandary 😉… I thought I had a fairly firm idea of what I wanted to end up with but now I have a nagging question… Drop bar Vs alt bar?

    So far I have a pair of drop bars, an old set of tiagra 4700 brifters (left/front shift doesn’t work), tiagra 4700 rear mech and some mechanical disc brakes. I have also ordered one of those exotic carbon forks.
    I can throw all this onto the radon, and with the additition of some bartape and new cables & outers id be pretty much there. I’m trying to figure out how to mount an XT shifter on a drop bar to retain the front mech/crankset by modifying a clamp on bottle mount.
    This would result in nearly what I originally wanted however it will be mechanical discs. Shifters could be upgraded if I’m happy it rides how I hope it will.

    Or i can go with something like Koga Denham bar, the new fork, and I’m pretty much ready to go.
    Minimal effort.

    Both options are very attractive.

    Cost wise the difference is about £50 of a difference in favour of drops so not really a biggie. (Unless I buy new hydraulic shifters 😉)

    Premier Icon gs_triumph
    Free Member

    Radon Team ZR with drops

    See attached image of the MTB with mock up drops in place.

    Measuring from the top of the seat tube to the top section of the bars is 24in which compares to 25in on my gravel bike.

    Premier Icon gs_triumph
    Free Member

    I should probably make clear i have no idea if thats a meaningful measurement or not 😃

    And I’d be using a short drop & reach Ritchey Venturemax or Beacon in the longer term.

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