Tangent 6kw fat bike components

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fullofdays
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Tangent 6kw fat bike components

Post by fullofdays » Apr 01, 2018 8:48 pm

Purchased a 6kw ascent kit from Dave last year and then my son was born. Just getting back to my first build and could use some guidance on components.

I purchased a carbon fat bike frame and bluto fork.

http://www.xmcarbonspeed.com/Productinfo.asp?f=1462

Going with a custom hi c battery

Thinking single speed (or high/med/low) but not sure what gearing or where to buy steel components? Don’t think shimano/sram make components that will work but perhaps someone can advise?

What size brakes will work best?

Are carbon fat bike wheel sets durable enough for 6kw or do I need to go aluminum?

aCeMadMod
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Re: Tangent 6kw fat bike components

Post by aCeMadMod » Apr 02, 2018 11:10 am

hi stick with steel frame if you can.

carbon for fun ride not to last it will do if done right help make them last

carbon super strong .. till it breaks

steel blend then cracks it safe in my view


I own 40 frame in my life


all the best 8)

Solaire
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Re: Tangent 6kw fat bike components

Post by Solaire » Apr 02, 2018 11:41 am

my 2c.

I agree that steel is going to be a better option for frame durability. A couple pounds of weight isnt going to matter that much with a 6kw motor. I d probably personally go with a Surly for a Fat bike, they are pretty tough, and cheap used on ebay.

Onyx racing products make the HGSS-EP hub, that is only availiable through email enquiry that is a beefed up sprag SS hub, that they say will handle a tangent no problems.

Karl of EBB recommends a nexus 3 hub for the tangent, you could head to his blog and ask him how its holding up.

I recommend Shimano XT Brakes with 203 rotors. Big is better with rotors.

Also if you end up going 29+ i recommend the Vee 3.25 bulldozer. ITs awesome. The Jones Bikes 29+ rim should be strong as any carbon rim out there.

For gearing you could use one of these

https://www.ebay.com/itm/Shimano-XT-CS- ... 4902.l9144

Which are strong, and you can use derailleur or adjustable tensioner to try different gearings, and should fit on SS hub.

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tangentdave
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Re: Tangent 6kw fat bike components

Post by tangentdave » Apr 02, 2018 4:11 pm

The drive unit will produce ~375RPM into the crankset, which on a 26" wheel is 29mph (1mph/13rpm). A singlespeed setup should use a rear cog of similar size to the front chainring, say 32t->28/30/32t. The cog you use the most should have the straight chainline to minimize driveline wear under full power. A standard rear cassette works great (like the Shimano CS-HG500), the best option is a cassette with all the cogs mounted on a carrier to prevent individual cogs from digging into the freehub body, but many cassettes (including the CS-HG500 series) mount the three largest cogs on a carrier, so if you plan it right, the motor will be used mainly with the three large cogs and the remaining smaller cogs can be for pedaling or street cruising (they'll be very fast).

My singlespeed setups use the largest 3 cogs on the carrier like Solaire suggests. Just line up the size you want with spacers.


-dave
Peregrine DH/Tangent 8kW
tangentmotors.com

fullofdays
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Re: Tangent 6kw fat bike components

Post by fullofdays » Apr 02, 2018 5:33 pm

Thanks guys. The nexus 3 is out as my frame has through hole dropouts. I’ll look into these other components this week.

Solaire
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Re: Tangent 6kw fat bike components

Post by Solaire » Apr 02, 2018 8:05 pm

If you are running 5" X 26" tires, 27.5 X 4.5 or 29+(3"/3.25") your tire circumference will be about 15% larger than 26" @ 2.5" tires.

https://surlybikes.com/uploads/download ... eo_VF_.pdf

markz
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Re: Tangent 6kw fat bike components

Post by markz » Apr 07, 2018 4:55 pm

I scored a Shimano Nexus 3 speed hub for free, it was on that bicycle that was abandoned. And the front and rear rims are both double wall and 36H.

You think the Nexus can handle mid drive duty?

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ferret
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Re: Tangent 6kw fat bike components

Post by ferret » Apr 08, 2018 4:39 am

fullofdays wrote:
Apr 01, 2018 8:48 pm

What size brakes will work best?
I'd go with 203mm rotors, front and back.
Larger is overkill and would require a custom setup.
No real reason to go smaller, unless 203mm unapproved for the frame or fork by the manufacturer.

Avner.
Don't believe everything you think.

Cove GNG-Spot build thread

Astral Rune build thread

FastJohnny
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Re: Tangent 6kw fat bike components

Post by FastJohnny » Apr 15, 2018 8:48 am

Your build is close to my heart. I actually begged Dave for a 100MM adapter years ago and built the first Tangent powered (3KW) fat bike. These days I'm running a 6KW Tangent All mountain setup. I've tried all kinds of gearing combinations with these bikes, and have a pretty good feel what brakes work with what.

First order of business is going to be what chainrings to use. Your inner chainring that goes to the motor is going to need to be the smaller 24T most likely so it won't rub the chainstay.

I hate these chainrings personally because they are weak, it's easy to bend the teeth, and the chain tends to pop up on the teeth. If you can run a 30T 104BCD chainring on the inside with enough clearance to the chainstay I'd recommend it.

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If it's too close then you need to go to the 24T, keep in mind the Tangent has enough snot to bend a cro-moly steel frame to the right and that chainring will saw your chainstay.

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As far as rear gears I'd recommend starting with a cro-moly or at least steel freehub body. You'll want a cassette where the cogs are joined together and not individual cogs. Individual cogs will apply all the torque from the motor into a single spot on the freehub body and indent/eat away at the freehub body.
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For brakes I'd recommend 203MM rotors front and back, and 4 piston brakes. The additional rotating mass of the wheels and tires makes everything harder to stop.

Image

The Shimano ZEE's and XT 203 rotors would stop this bike in a hurry. The only issue was that with QR skewers in the front instead of a more modern thru axle setup, there was so much braking force it would pull the axle out of the right side drop out and cause the disc to rub the pads until I stopped to fix it. I have the same brakes on my current bike with thru axles and this isn't a problem.

I should prob show a pic of the bike huh?
Image

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