[How-To] ballsy nankai freecoaster mod

[jwnolte]

This mod will make your nankai freecoaster smoother and stronger. you will need a Nankai 24mm cone wrench (http://flatlandfuel.com/index.asp?PageAction=VIEWPROD&ProdID=230), a big adjustable wrench for lock nuts, some thick grease and some extra ball bearings. the bearings inside the driver on my 11t are bigger than the bearings inside the shell, so make sure you get the right sizes.

The bearings that come in a Nankai hub look something like this:

we are basically going to eliminate those cages to make room for more bearings to make the hub smoother and stronger.
push the bearings out of the metal cages inside the hub so you have nothing but loose ball bearings.

actually, you could probably do this to any unsealed part and get better performance with it. Those of you who are plagued with an unsealed bottom bracket, take note.

1. "glue" all the bearings to the cones with grease, not the hub shell. i think you need 17 on each side of the shell and 10 in the driver? do the right side first- push all the balls in close around the inner part of the driver, not out along the sides of the dust cover. The driver will not fit right in the hub shell if the bearings are too far out.


2. secure the driver so it doesnt shift, causing all the bearings to fall out. I like to put the drive-side shell bearings in first, then thread the clutch in. I wrap a rubber band around a spoke and wrap that around the driver to keep it from un-threading itself and falling out.


3. arrange the left-side hub bearings. make sure the cone, lock nut and outer nut are all tight.


4. carefully slide the axle with the cone assembly in place and set the axle upright on the floor/bench so it doesnt fall back out. if the axle doesnt go in all the way, either you have too many bearings on the cone or the bearings have shifted and are not fitting into the shell correctly.

5. grease up the outer race of the driver. the driver bearings in my 11t driver are slightly larger than the hub body bearings. make sure you are using the correct size bearings! i put a little o-ring under the cone nut to keep some of the dust out. drop the bearings in around the axle with lots of grease and thread the right side cone nut on slowly.


6. now take that rubber band off. tension the cone nut and tighten the lock nut against it. a Nankai wrench is absolutely necessary for the finishing touches.


lemme know if you have questions.

[inertia haydes]

i have a question which is .. i have nevr had a freecoaster before and i was just wondering how long a half descent one would last for street riding and a bit of park now and then.

[jwnolte]

that's a question for the "freecoaster questions" thread. but i will answer it here:

that depends on how hard you ride it, which hub you have and whether or not you take care of it. a good freecoaster will last as long as any other hub if you are not a hack and you take care of it.

if you run pegs, get a nankai bamboo hub. first you have to find one though...

[Karl H. Marx]

Very good idea.

I'm guessing the bearings unstick from the glue when you're actually riding it yea?

[jwnolte]

don't use actual glue! just use a thick grease that acts as a "glue" to keep the bearings in place while you assmble the hub. i used Park Polylube1000.

[Karl H. Marx]

don't use actual glue! just use a thick grease that acts as a "glue" to keep the bearings in place while you assmble the hub. i used Park Polylube1000.

Ohhh.

Makes a lot more sense now!

[Italianbmxer]

I dont see the mod part in this for other unsealed parts?

What I see is a guide of how to easily put back together the nankai hub...what am I missing?

[jwnolte]

the bearings that come with the hub come in cages like this:


if you pop those bearings out of the cages, you have more room for more bearings. more bearings=more surface area contact between hub and bearings=strength. unsealed bottom brackets usually have cages like this as well and i believe a bottom bracket could be made stronger and smoother if you put it together this way.

[lewis211]

its like doin brain surgery puttin looseball bearings in, its really really awkward and fiddley.

[jwnolte]

only if your hands are awkward and fiddley. i did this no problem and i can take the whole hub apart and put it back together in less than 30 minutes. it's worth the effort.

[Italianbmxer]

AH!

I have seen only 1 Nankai come in the shop. It wasnt even for anything tech,I think it was to....something with the chain (not slack)

but yeah,I assumed that the Nankai came with (theyre called free ball bearings) :)

I can't think of any place to get ball bearings off the top of my head,Ill ask around at the shop....friday...to see if theyres any place to get them. Also you could e-mail Nankai Im sure?

whatever,your mod,don't want to hijack this :)
+rep if I can

[jwnolte]

flatland fuel sells the bearings, but my local bike shop had some in a box of spare bearings. they seem to be a pretty common size.

[Italianbmxer]

yeah, I looked we had some at the shop. i guess just one of those parts that shops have that 1 person comes in for every other year

also,before anyone tries this,you might want to point out pedals dont have cages on them. unsealed pedals come with this done already,and if you make the mistake of trying to do this mod, youll end up with your bearings all over the place....

[Lewy]

if i wanted to do this with a intergrated headset then would it just be the same

[JonMack]

Yeah, exactly the same.

[jwnolte]

i dont' think it would work on an integrated headset. there are no cone spacers for the balls. it might be possible, but tricky.

[KODYO]

I dont have a free coaster, but do you think the same idea would work with an unsealed BB?
Mine is giving me problems (whats new right), but do you think i would be able to replace the cage with berrings of the same size?
check sig for bike pics

[jwnolte]

yes, i think this same idea would make a stronger, smoother bottom bracket or any hub. i have heard that some people did this to their unsealed press-fit headsets too.

[wozza]

yeah i did this to my FSA the pig headset, made it so much smoother and it just feels stronger.

[KODYO]

I have a question, when you replaced the bearings, did you put one bearing in for every spacer of the cage?

As far as i can tell, this is not possible for my bb. Or should i just put as many in that will fit without it being too tight?

If there is a small space will that completely mess it up?
thanks

[jwnolte]

it depends on the part you are changing, but there is probably not enough room to double the number of bearings. i would say put in double the number of bearings minus one to three bearings. just make sure they are packed in tight, but not too tight.

[grr]

whats the actual mod
i dont get what your doing

[sam8madness]

go to the first page and read the comments

good idea, bearing cages suck

[jwnolte]

whats the actual mod
i dont get what your doing


we are basically going to eliminate those cages to make room for more bearings to make the hub smoother and stronger.
push the bearings out of the metal cages inside the hub so you have nothing but loose ball bearings.

did you read it at all?

[KODYO]

More like, did you even read the first paragraph?
I will try the mod next time i have problems. But i already replaced the bb with new bearings in cages, and would rather ride it than mess with it. I think the problem was the actual cage on the bad bearings, i think it was warped a little

[sam8madness]

yah those cages fall apart in no time

if one is ever bent or anything just get new ones or use this method

[KODYO]

next one that bends im going to do this, because i will already have enough bearings and nothing to lose.
Thanks for the mod

[KODYO]

OK, so i did the mod on my bb. First try took about 15 minutes to do, but put crank shaft in wrong way, so they all fell out. Next try took me 25 minutes, but i put one to many bearings in, and when i tried to take it out, the bearings fell out. The final try took me like 45 minutes.
A big tip while doing this on an unsealed bb, get a magnetic screw driver for sure, when they fall in the housing, which they will, they are very hard to retrieve, unless you have a magnetic screw driver of course.

They ride extremely smooth, and no more noise.

Hoping this cures my problem.

Another thing to keep in mind when doing this is when you tighten your bearings back in. Hand tighten the other half of the bearing housing (can be slightly tighter than hand, for reasons you will soon see), put the washer on, then hand tighten the flat hex nut. Once the hex nut is tightened, loosen the bearing housing under neath it by putting a screw driver in the slot on one side, and tapping it to the right. Note: the screws are reverse threaded (right loosy, left tighty) . This will keep the bearing housing from over-tightening while you pedal and will secure the housing.

hope this helps anyone wanting to do an unsealed bb, with little biking experience

If someone needs clarifying, or pics, i would be more than happy to

[jwnolte]

thanks for the tip. one other thing to consider when doing this mod on a bottom bracket- don't let the bearing fall into the vent holes in your frame! you will get bearings rolling around in your top tube and down tube.

count the number of bearings that fit in your BB and keep that number for future reference.

use THICK grease to "glue" the bearings in there so they are less likely to fall out while you are working on it. try to let gravity keep them in there whenever you can.

[KODYO]

I used waterproof phil grease, worked perfectly

[Italianbmxer]

yeah instead of just putting them in the cups,coat the cups with grease. they won't fall out or around or any of that.

[KODYO]

yeah, i put a drop on each bb, then put it in there, stuck surprisingly well. Well enough to turn the frame upside down and have none of them fall out

[kitch]

word up man great mechanical ingenuity! rep for that! i have the opportunity to buy a nankai from a buddy of mine i just might now.

[olie991]

so what size are thease bearings? i need to order some fast

[RID]

looks awesome