[Closed] Would you buy a (new) fatbike for ~£1k?

roverpig - Member

Great picture, but why do so few fatbikes have dropper posts fitted? It was the thing that surprised me most when I had a demo on a Surly Ice Cream Truck; a hooligan of a bike, but no dropper!

I think a lot of people still don't see them as trailbikes tbh. And also see droppers as a thing only trailbikes need. (I put one on everything, my XC race bike had one and was all the better for it...).

Also though I assume if you regularily beach ride you'll kill any dropper in pretty short order?

We're getting a bit off topic, but surely XC riding (as opposed to racing) is when you most want a dropper. If you just winch up and plummet down a dropper may not be that useful, but for the frequent short downhill sections that you get on a typical XC ride they are great.

Fair point about beach riding though. I guess that kills anything that moves pretty quickly.

My fatty has always had a dropper, but I ride all trails I would on a normal bike

re the 4.0s vs 4.8s they're both good tyres and have their own characteristics

The 4.8s are definitely more floaty but by the same token they bob more. The 4.0s are a bit more critical on the pressures and have a slightly harsher ride but they don't bob as much, the steering feels more accurate and depending on where you ride they are easier to thread through narrow gaps. They don't get hung up/smear off stuff as much as the 4.8s

But the 4.0s are also less flattering than the 4.8s I have to ride the 4.0s with a bit more finesse instead of just riding over/through everything

A 4.0 on the back and a 4.8 on the front is a good compromise but personally I prefer the 4.0s f&r now conditions are drier

roverpig - Member

We're getting a bit off topic, but surely XC riding (as opposed to racing) is when you most want a dropper. If you just winch up and plummet down a dropper may not be that useful, but for the frequent short downhill sections that you get on a typical XC ride they are great.

Aye, that's exactly how I feel too.

I've spent far too long trying to work out the intricacies of fat bike chainline/hub spacing/q factor.
In summary, its a bloody mine field and I almost wish I never bought the bloody thing as upgrading the cranks for optimum chainline presents a clusterf@€k of options.

Northwind - I'm settling on the Aeffect crank arms as amongst other reasons it appears they are compatible with my Hope BB - can I ask what paid for yours and with which chainring/arm length/axle length?
You mentioned pages ago about not being convinced about your chainline - i've devoured plenty of charts and reading and I 'think' the best option for a 190 spaced hub is to go for the shorter RF fat axle (167mm) and flip the direct mount chainring.
This gives a chainline of 72.5-74.5, close to ideal optimum, and a Q factor of 205mm.
With the 190mm axle you're running a chainline of 77.5-79.5mm and Q-factor of 228mm.

If you purchased the longer axle, then you could probably source the shorter version if you can be arsed?
This is theoretical at the moment as I am yet to measure my current Q-Factor and check the arm clearance on the chainstay. There's a possibility (I suppose) the the 205mm may not provide enough clearance.

Lastly, Woofstooth components make offset cinch chainrings (inc. oval) which im sure would offer you the chance to tweak your chainline further. I have several charts saved if you need them.

I think I paid £110 or therabouts for my Aeffects... For the 170mm. And yep as you say the narrower axle and a flipped ring- clears a 4.8 JJ or Bud with a bit of room to spare, not generous but more than adequate. I got it wrong first time and ordered the 190mm version, it's miles wider than a Dune needs. (mind you the 170mm version could be iffy with a double, I do not care).

Chainline's fine- not quite perfectly centred but tbf, I just don't care. It's not like you spend exactly equal times in every gear anyway. I reckon it's mostly a thing for the anally retentive to worry about rather than something that matters. If memory serves, it's ended up slightly offset to the inside which actually sounds like a not bad idea considering how much longer I spend in the low gears plodding up hills.

I got an absoluteblack oval... I think I was just too fast for the wolftooths. Which is a shame because absoluteblack geezer is a total fud and I didn't like giving him any money, or dealing with the pisstaking delivery times afterwards.

Droppers for fatties: Decathlon cheap non-remote comes in a 31.6, 100mm drop, 400mm post if you can find one. Mine cost £35 delivered last autumn and it's been great through it's first winter, perfect for the hooligan behaviour that a fat bike encourages. Mine doesn't do sand but a cruddy would help a lot with that anyway.

Anyone got crank or preferably replacement 104 ring ideas for the X5 on an O-O fatty?
Is it just a case of taking a grinder to a standard Shimano Deore steel 36t?

I reckon it's mostly a thing for the anally retentive to worry about

I'll be losing sleep tonight over this matter!

Am wondering myself about going for 170mm's, owing to my stubby legs.

Anyone got crank or preferably replacement 104 ring ideas for the X5 on an O-O fatty?

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Got aeffect cranks with Shimano BB here, and I'm not sure what I'm doing with the crank nut.

If I tighten to 45 ftlbs, the BB doesn't spin freely, if I back it off to where the cranks spin freely, the bolt and the crank come loose in a few miles riding.

I've got 2 spacers each side, any fewer and there was room for the cranks to move side to side in the BB.

What am I doing wrong? Any ideas?

is it an mtb or road shimano BB?

I've got 2 spacers each side, any fewer and there was room for the cranks to move side to side in the BB.

Presumably it only matters when the bolts are done up though?

I've not used the newer RF cranks but the older ones had a rubber X-ring as well as the spacers, so add 1mm spacers and the rubber one takes up the fraction of a mm.

mtb HT2 BB.

I started with 1 spacer DS, then went 2DS 1 NDS, there was still a little room on the spindle when the crank nut was done up tight, so I put in another spacer.

??

I've got a gusset ext24 with my aeffects, which is pretty much the same dimensionwise as a shimano ht2. And likewise, 2DS 1 NDS spacer just like a 68mm shell, worked a charm.

Cheers nw.

So you tighten up the crank nut to 45ftlb and you're all set, no loosening of the nut and crank or stickiness in the BB bearing?

Bit confused how the bearings get preloaded correctly, without the adjuster you get on the Shimano cranks.

http://www.planetx.co.uk/c/q/deals/pay-day-7-day-frame-sale?sort=price-asc&utm_source=web&utm_medium=banner&utm_campaign=Tbar7DFS

Fatty Trail frame £80 (less Topcashback)

The burning issue is can you wear Lycra on a fatty?
When it gets hot I find baggies of any kind too hot. All my other bikes are suitable for Lycra so what say ye?

In my case, yes. If I want to look like a string of sausages.

nedrapier - Member

So you tighten up the crank nut to 45ftlb and you're all set, no loosening of the nut and crank or stickiness in the BB bearing?

Bit confused how the bearings get preloaded correctly, without the adjuster you get on the Shimano cranks.

Aye. Basically, if everything's the right size, then torquing the axle down fits everything up perfectly and takes out the play. Obvious possible issues with this are obvious. But it does work.

So that's it hopefully race ready, soloing the Glentress Seven on saturday. New wheels ridden on but not really tested, tubeless waiting to see if it stays up overnight (there's a plan B but it adds about 150g per wheel), bottle cage and saddlebag fitted but not filled, 4.8 JJ on the front and 4.0 on the back, 150mm dropper and 780mm wide bars... 27.2lbs. Not bad for a supermarket bike...

What wheels did you go for Northwind?

[i]Practically[/i] BR2250s- I got some cheap DT big ride hubs off ebay, from some weirdo that had downgraded to Hope, some BR710 rims, and
sapim lasers (*). Worked out a bit lighter than BR2250s, but more importantly cost me less 😆 Nice collection of parts, but assembled by a know-nothing idiot, me. So we'll see I guess.

Done them up with pallet wrap tubeless but I'm not very convinced that's going to hold. I found fitting the tyre with these tighter rims a lot harder with that method than it was on the dune and I don't think the wrap's quite right. Don't have time to troubleshoot it properly so I might have to revert to split tubes to get it reliable for now. Tested that quickly and it worked a charm (and stayed inflated for 2 days with no sealant!)

Very pleased anyway. It's a big weight reduction over stock, expensive obviously but I think it's worth it going by the testride.

(* incidentally I know Sapim don't recommend these for mtb use but I've had them in my #enduro 29er wheelset for a year and they've not flinched. They're equivalent to Revs, only cheaper. I did think about going with the CX-Rays- which is literally the same spoke, squished flat- for the critical aero bonus and wallet weight reduction)

Why only 4.0 out back? I may have missed that bit but the thread is huge lol 🙂

I'm debating now going 1x11 as the new 11-46 sunrace cassette is out and should go nice with a 32t oval ring on 104 cranks

Those dtswiss wheels are the boll*cks. I run them with jumbo jims on tubless and they feel so quick..ow much did it cost you all in for the wheels? I paid £480 for them from Ze Germans but have failed to find them in stock ever since.

Sorry to hijack this thread but was looking for some advice , Its cyclescheme time and I was considering a new bike. I have a Orange Crush for the woods and a carbon pro for the road so was considering either a fatbike or a cx .
Anyhoo my options are Genesis Caribou £880 , Felt DD70 Or Calibre Dune for £579.

What do the experts think. ?

It would be for the usual East lothian trails and a saunter down the East lothian coast.

Sorry to hijack this thread but was looking for some advice , Its cyclescheme time and I was considering a new bike. I have a Orange Crush for the woods and a carbon pro for the road so was considering either a fatbike or a cx .
Anyhoo my options are Genesis Caribou £880 , Felt DD70 Or Calibre Dune for £579.

If you are a basic rate tax payer, it might be cheaper to buy the Dune over this bank holiday...
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Anyone fancy Maxxis Mammoth Exo 4.0s for £40? Best price I've seen for these by some margin! 😯

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firestarter - Member

Why only 4.0 out back? I may have missed that bit but the thread is huge lol

Usually it's 4.8 both ends but I'm going XC racing 😆 So I've taken the minion off the front, put the 4.8 JJ from the back, on the front, and brought out my original 4.0 JJ to finish it. TBH I'd have used 2 4.8 JJs but I've only got one. It'll be back to minion/jj as soon as the race is done.

johnnyboy666 - Member

ow much did it cost you all in for the wheels? I paid £480 for them from Ze Germans but have failed to find them in stock ever since.

I think all in, about £380. Plus my time o'course. TBH it wasn't entirely about the saving, as you say stock for the BR2250 was really bad for a long time, and I nabbed the hubs on a whim. But it worked out well.

Cool cheers for the info

Had 2 Floaters delivered today, wrapped in a bin bag.

Looked and felt like a dead body. A heavy dead body. Light those tyres ain't

Floaters were weighing 1400g each or so, back at Easter, despite the marketing blurb.

How heavy are yours, slimjim78?

Anyone used those maxxis mammoths,any good?? Could do with a narrower tyre for the back.

I used them, great in the summer months super fast rolling. But leathal in any form of slop of wet ground

Worked out a bit lighter than BR2250s, but more importantly cost me less

Can you tell us what the standard wheels weighed, for comparison purposes when shopping for replacements Northwind?

I'm torn between spending more on the Dune, including upgrading to a large frame, buying a new frame/forks (after seat post, stem/bars) or getting some 27.5+ wheels/tyres for my FF29.

I popped into SLAM69 in Glouc yesterday. They've got some nice fat bikes in there including a beargrease with a leif fork that weighs about 25lbs. Also doing their own brand which look really nice and you can have in any colour.

The BR2250s on hope hubs look fantastic and are so light. I nearly left with a pair. Definitely the next upgrade for me.

Northwind,

Just read back through the last few pages,

I have a 9:Zero:7 190 frame with 190 spec cranks and they are very wide....
The bb shell is 100m

Do I understand that its possible to fit a RF 100mm 170 spec crank and flip the ring on the outside of the spider?

Im getting a bit hacked off with pedal strikes in ruts and a bit of a groin pull due to the wide pedal position...

their own brand which look really nice and you can have in any colour.

They are Smokestone "The Henderson". I have ordered one from the first batch. All of my OOF bits should swap across. I have seen them throughout the prototype process and Graham has put lots of thought into what people want and what makes a good fatty. Hoping to have the bike built for July. Will review it and let you all know how it rides, super excited to be honest!

Unfortunately all my current bits (hubs etc) are purple so I need to select a colour that suits them. That isn't just boring black! Decisions, decisions

Fahzunnd! Good work fatists.

Do I understand that its possible to fit a RF 100mm 170 spec crank and flip the ring on the outside of the spider?

smokestone 'the henderson'

Standard BR2250 wheels weigh 2250 grams although Several reviews I have seen they have come in just under that.

Slimjim have you been on the smokestone website?

http://www.smokestonebikes.co.uk/frames/the-henderson/

12x177 rear hub spacing so I can change end caps on my rear hub I'm told. 100mm Bb so my hope one will bolt in and I can then swap over my xt 12 speed and aeffect cranks. Will need a new headset and a stealth reverb but otherwise my bluto, fatsno br710's etc will all transfer over. I have seen the final prototypes in the flesh and swung my leg over one. It just feels right. Plus Graham is a great guy who is always happy to help. So I'm already sold with deposit down.

That Henderson looks good. And totally custom build, that's ace. I guess they're connected to Dartmoor in some way? (worth mentioning either the frame or bike spec is wrong, it says 30.9 and 31.6 seatpost so be careful)

jeff1155 - Member

Can you tell us what the standard wheels weighed, for comparison purposes when shopping for replacements Northwind?

Standard Dune? Mine were 1739 rear, 1490 front without rim strips (I can't remember what the standard strips are but it's more than you might think; I replaced mine with pvc tape, works great and weighs nowt.)

TBH the dune wheels have been fine for me but I was loving the half kilo an end weight saving today!

rickmeister - Member

I have a 9:Zero:7 190 frame with 190 spec cranks and they are very wide.... The bb shell is 100m

Do I understand that its possible to fit a RF 100mm 170 spec crank and flip the ring on the outside of the spider?

It's complicated, basically. Which 190 cranks is it? If it's raceface we might be able to do some useful comparisons... It'll depend on the frame though, I did the flipped ring thing with the 170 Aeffects on mine and it fits well- not too tight, not too far, perfect really.

And yeah, that q factor change is worth it imo, there's trails I ride where the cranks are physically too wide (broon troot at glentress requires a planned pedal smash on one corner, or maybe some ninja lean moves, otherwise both pedals ground out!)

The first proto was 30.9 but the production bike is 31.6. I remember discussing it with Graham

How much are the pre-production frames costing russy?

How heavy are yours, Slimjim78?

Just weighed them, 1360 and 1340. I've been spoilt by my Juggernauts I think.

EDIT* just got the link above working on my iPad..450 notes for the frame eh? Ouch. Looks like I'll be enjoying the Dune for at least another season then.

Production frames are £450 I believe although I'm sure it will depend on what you wan sorting paint wise.

I liked the polished prototype. What's the deal with having them done any colour then?

Good stuff, 30.9 can **** off.

RACEBIEK!

[URL= http://i74.photobucket.com/albums/i264/Northwindlowlander/mountain%20bike/Dune/IMG_0405_zps0xxnjod1.jp g" target="_blank">http://i74.photobucket.com/albums/i264/Northwindlowlander/mountain%20bike/Dune/IMG_0405_zps0xxnjod1.jp g"/> [/IMG][/URL]

Ended up a bit over the 27lbs as I went back to split tubes for the tubeless- first attempt at wrap failed, it'll work though I'm sure. Standard dune photography issue, the sun was out so it was glowing 😆 Never missed a beat all day, 6 laps which made me I think 28th in solo males under 40, out of about 50, I'll take that.

To be fair, it would be best speaking with Graham. I have just booked a medium frame from the first batch. He has selected the colours on the website as standards. But I believe you can select something different if you so wish. I am likely to go the flo green or electric blue

Bloody hell , STW hasn't changed at all. You ask a simple question re Budget fatbike choice and get totally ignored only for cock measurers to then get out the tape measure and scales to weigh there fud chariots and publish thier findings.
Would it seriously kill you to give a little guidance to non ****stanes and give some guidance....

That's the Calibre Dune I bought from a supermarket for £500. A look at all the people who've subsequently bought this bike because of info in this thread might help you pull your head out of your arse.

As for giving a little guidance, tbh I wouldn't want to set my sights so low. Still, [i]your [/i]contribution to the thread is surely of great value.

It's amazing on the pic how the 4.8 makes the 4.0 look small

Northwind, what are your ready to roll wheel weights?
My fatty weighs about 6 lb more with a carbon fork and I can only assume that extra weight is in the wheels.

Stanfree, that's a poor and inaccurate summary of a >1000 post thread.

Because obviously you've read the entire thread before wading in and insulting the contributors, right?

There are two fat bikes available for less than 500 quid discussed regularly here, so half the OP's threshold and hardly "fud chariots".

Stanfree - it's '**** stains', you cock monkey.

zippykona - Member

Northwind, what are your ready to roll wheel weights?

The wheels are just under 2200g and I think about the same for the tyres- the split tubes just now add maybe 130, 140g IIRC, the pvc rim tape weighs grams.

TBH everything on the bike is light, except the dropper- it's mostly parts I already had but they're from my old XC race bike and Ragley Ti so there's no flab. Ti bolts on a fatty 🙄 Frame and fork is only about 2700g inc complete headset so barely more than the Fatty frame alone. The Dune fork is light but quite nasty, very harsh, I reckon your carbon will be a lot nicer to ride on tbh but it's only a little lighter. (I'm kind of amazed that this makes a difference with a 4.8 tyre but it does)

(*incidentally; I've mentioned this before in the thread but most people recommend the Schwalbe AV10D for split tubeless on an 80mm rim. I used an AV10 and an AV10D on the stock dune wheels and these are the sv10 (same tube, presta). It's a fair bit lighter, and fits an 80mm rim absolutely perfectly so no excess, no trimming, you can see it there but only just. More importantly, much cheaper and more available- I paid £3 a tube from halfords instead of the £11 the AV10D I used first. You need to be sure to cut it tidy and get it centred mind but imo it's just the better choice)

/\ good tip, thanks.

Is it possible trim the tube short of the rim bead so that it's not visible externally ?

Not sure... But it's just a mm or so it pretty much blends in, I don't think you're likely to care once it's on. Unless it protrudes more on your rims anyway. I think if you cut it down it might quickly become a pain to get it in exactly the right place to seal...

(I was surprised btw, I thought the tube would mess with the rim bead on the DTs but it still retains the tyre well)

For slimjim:

[URL= http://i74.photobucket.com/albums/i264/Northwindlowlander/mountain%20bike/Dune/IMG_0415_zpsqnro1ors.jp g" target="_blank">http://i74.photobucket.com/albums/i264/Northwindlowlander/mountain%20bike/Dune/IMG_0415_zpsqnro1ors.jp g"/> [/IMG][/URL]

[URL= http://i74.photobucket.com/albums/i264/Northwindlowlander/mountain%20bike/Dune/IMG_0414_zpsk639s513.jp g" target="_blank">http://i74.photobucket.com/albums/i264/Northwindlowlander/mountain%20bike/Dune/IMG_0414_zpsk639s513.jp g"/> [/IMG][/URL]

It's not too obvious that there's a tube there, this one was a wee bit uneven but I figured that'd be more useful for you- the other end is a bit tidier. Up close you can see and feel that there's a flap but from any distance it just kind of looks like the bead strip on the tyre.

Aye looks good. Those rims look ace too. What's the most noticeable aspects after fitting them?

Great thread...

Ill just leave this here from this week.......

[img][URL= http://img.photobucket.com/albums/v633/rickmeister/P1220093_zpsgxqzeiy8.jp g" target="_blank">http://img.photobucket.com/albums/v633/rickmeister/P1220093_zpsgxqzeiy8.jp g"/> [/IMG][/URL][/img]

Just the weight really, it picks up and accelerates much nicer and it's that much easier to maneouvre. Definitely a plus for a trailey fatbike. TBH I found the stock dune wheels totally satisfactory though.

Great thread...

Ill just leave this here from [s]this[/s] last week.......

and possibly for sale to fund a new project...

[img] [/img]

Is that near Widdop Bregante?

Blackstone Edge - above Littleborough. Hollingworth Lake in the distance.

18" Voodoo Wazoos are listed as 4 available on the Halfords Ebay store today, after seemingly running out of stock several weeks ago...

http://www.ebay.co.uk/itm/VooDoo-Wazoo-Fat-Bike-Bicycle-26-x-4-Tyre-16-Speed-Alloy-Frame-Mud-Snow-Sand-/201373335552

Halfords own 10% promo drops price to £449.

Go to Ebay via Topcashback to get 4.4% back until end of 31st May.

Fell off my Dune for the second time over the weekend, ouch my ribs are sore - very similar to first time, in a tractor track, hit the edge of the raised central section, lost the front I imagine - I wasn't aware of anything except instantly flying through the air, then landing on my shoulder and banging my head on the ground.

Things is, before the Dune I hadn't fallen off a bike for 30 years, even if only the last 4 has seen me cycling a lot more, but now I've done it twice in three months and hurt myself. Are Jumbo Jims susceptible to washing out, am I travelling faster/over confident with fattie tyres, or am I just an idiot who needs to stay away from tractor ruts or get some training?

What tyres and pressures are you running?

Ruts are weird sometimes for fatbikes just because every rut is basically narrower- it's much easier to clip a pedal or barge the tyre into the edge, when the tyre's wider. Could it be just that?

The JJ's not the grippiest tyre for sure but it in the dry it does have decent grip. As long as it's on the ground anyway! If the bike's bouncing, it's a different story.

What tyres and pressures are you running?

Jumbo Jims, tubed on stock wheels, at 9psi. I could let skittle more out, I've never felt them close to bottoming out, but they roll nicely at that pressure, but I can see it might make the side wall overly stiff and not compress when riding up the side of a rut?

Incidentally I also installed SV13F tubes, but I can't get the tyres to seat on the rims evenly - one section always sits inboard and a bit lower, giving me a nice oval tyre...?

I'm not sure about these SV13Fs, they don't seem to fill the tyre nicely, if that makes any sense? As if they're just struggling to stretch to 4 inches. I can't really rationalise this but that's the impression I had...

OK, I was thinking the pressures might be too low, leading to a bit too much self-steer. But 9psi should be enough. Maybe best just to avoid ruts for a while 🙂

The results are in!

My hunch was right, Kenda Juggernaughts are slow. Unsurprisingly Schwalble and Specialized are 1 and 2 given their reputations for making fast tyres.

Be interesting if someone sent him a Floater, my impression was it was faster than the Juggernaught but I've not tried enough others to rank it.

http://www.bicyclerollingresistance.com

(edit, the site has nothing to do with me, I just got shot down a few pages back when I offered to swap floaters for Juggernauts)

Interesting test, but presumably it's only really relevant to riding on a smooth road.

For example, the test implies that we should be riding at pressures as high as 20 psi to reduce rolling resistance. Fair enough, on a smooth road a higher pressure should be better as it means less sidewall deflection. But once you add bumps you lose a lot more in lifting the weight of the bike+rider up and down and a softer tyre, which rolls over the bumps, can be faster.

Interesting test, but presumably it's only really relevant to riding on a smooth road.

For example, the test implies that we should be riding at pressures as high as 20 psi to reduce rolling resistance.

The winner was the liteskin Schwalble, and the differences were most apparent at 8psi.

If rolling resistance is a measure of how easily the carcass deforms over the drum, then I'd actually expect the difference to be even more marked off road as each little bump is like a miniature drum that the tyre has to deform over. Or at least neutral, for every bump you go over, there's a hollow that the tyre doesn't have to deform into.

50W saving at 18mph, even if that's halved at normal speeds 25W isn't a gain to be sniffed at.

So far I can only comment on the Juggernauts, but I have Floaters and a Fat b Nimble to try out. The Kenda's seem to roll fairly well off road, plus they are so much lighter than the others. I'm also running them at around 9psi, may try dropping the front pressure next ride out. That being said, on hardpacked flat bridleways I do notice drag but have just assumed this is a fat phenomenon. Will be interesting to see how a heavier Floater, for example, holds up on the same flat sections.

I've been revelling in off camber 'rut' grip recently, and rolling up curbs at bad angles is also being taken in their stride.

I haven't been out on anything other than perfectly dry trails yet but I'd be surprised if they hold up too well with such a shallow tread profile.

Not looking forward to the mud though, I'll be adding a kilo of tyre weight when I swap over.

If rolling resistance is a measure of how easily the carcass deforms over the drum, then I'd actually expect the difference to be even more marked off road as each little bump is like a miniature drum that the tyre has to deform over.

Yes, I guess that's right. I was questioning the fact that higher pressures were more efficient as I think that only applies to a smooth surface. But the comparison between the tyres at the same pressure should still be valid off road I guess. As you say, it's mostly a measure of how much energy is lost in deflecting the carcass.

Did they test and 4.8" tyres? I couldn't find any, but it would be interesting to see a comparison between the JJ 4.0 and 4.8, for example.

Fresh goods Wednesday, received my Aeffect crank and Absolute Black oval ring today - initially chuffed that they both turned up at same time only to find that Sham69 have bloody sent me 170mm cranks over the 175mm i ordered.

I HATE sending stuff back. Should I live with the 170s and revel in significantly less rock strikes?

Changing (back) to shorter crank arms won the Giro for Nibali.

Though not on a fat bike.

bet you'd be absolutely fine with the 170's. Possibly better off than with 175s. Unless you're really tall?

I'd keep em. but then bought 170 aeffects in the first place.

Which are all sorted with correct spacers and torque and staying put. Cheers NW!