Just building up the above bike. I’ve fitted an xt cassette with 50 tooth one up ‘shark’ low gear and a 30 tooth sram chainset. The chainline is poor catching the tire (On-one floater 4″) with the lower chain in the two lowest gears. Moving the two BB spacers to the drivetrain side improves the chainline slightly but it still catches in the lowest gear.

Does anyone else run a 1×11 setup on their trail fatty (or similar) with no issues?

I’m thinking the easiest fix may be to switch the rear tire for a narrower one. Does anyone know of a website (I’ve failed to find one with google) which has the real width of tires (I’m on 80mm rims)? Can anyone recommend a narrower tire?

Any other ideas for a fix/bodge?

Cheers

Chris

Have you thought about spacing the cassette across using the smallest cog behind the cassette. You’ll obviously loose your top gear but it might buy you enough room to get you chainline.

D.

I bought mine full build, and there really isn’t much room, between 5-10mm at a guess without measuring it.

Thanks for the reply. Davesport that is a great idea. I’ll have a play.

So, turning it into 1×10 is the solution? 😆

Boost chainset, might give you enough clearance.

If it lets me ride it 1 by 10 is fine for now. It will have the low gears I’m after. Fat bikes already use a 100mm axle so a boost its not relevant.

Cheers

Chris

Chris i can dig out the exact part spec for BB and 1x chainset on the fatty trail if you’d like?

How is the chainline otherwise? Is there any potential to move the ring outwards (similiar to how you can flip a raceface cinch ring?) Maybe, fitting a double spider and mounting the chainring in the outer position?

I’ve got a wider Q-factor Raceface Aeffect 100mm crank for sale which would push the chainring out by a fair amount but maybe it’ll screw the chainline in other ways. Is it a 4.0 tyre you have on it?

(on mine, I have a 197 rear and narrower 100mm crank fitted, 1x is fine even with a 4.8 rear tyre… But you have the narrower rear end which obviously pulls the cassette inwards)

Thanks Northwind. The chainline seems great otherwise. I’ve tried moving the cassette out this evening by removing one gear and adding a spacer. It’s improved things but still catches the tyre.

No potential to switch the chainring round /move it over. At the moment going to avoid buying a new crank. Think I’m going to get some calipers out on the tyre and find its actual width.

Did on one make a 197mm rear end or is it a different make?

I’m enjoying trying to get the fatty up and running but there seems to be a lot in getting a fatbike right.

Sq’ lots of numbers’. That would be great. I’m wondering if the long cage is causing the issue or whether I’ve done something daft.

Is it possible that your rear wheel is dished too far to one side?

Measure the distance between tyre and chainstay at both sides.
Try putting the wheel in the wrong way round and measure again.

Re-dishing the wheel should buy you a few mm.

Thanks Scotroutes, I can now access uk fat bikes and saw your response on there.

1×11 certainly works on a Specialized Fatboy with a 4.6 tyres. As for the On-One I don’t know, what is the rear axle width on those?

Otherwise Mr Northwind is very knowledgeable so listen to him not me. 🙂

We build them up fine with the Floaters and 1x 11 on GK or X1 chainset. I’ll get the numbers for the cranks, BB tomorrow.

How wide is your rim?

I run 1×11 xt on my oof (original non trail) with race face cinch crank and absolute black oval chainring in the biggest cog the chain does get close to the tyre but doesn’t rub. This is with both 3.8 Nates and 4.0 Fat b Nimble tyres? Happy to take photos if it is any help?

Thanks for all of your help. In the end I noticed the replaceable dropout was not screwed up tight. Tightening this improved things.

Redishing the wheel by turning each nipple 3/4 of a turn has now made a clearance of a couple of mm.

The chainline is pretty bad in the lowest 50t gear but that is due to the short distance from tension jockey wheel to chainring.

Thanks again.