Author Topic: Newby crank help (Read 1278 times)

bai13y · « **on:** April 10, 2008, 01:19 PM »

Hi guys,

Been reading the forum for a while and I've decided to build my first bmx (new skool for now,untill i get some money and some skills,lol) and found all the threads really helpful.

But now I'm stuck.

I have a diamond back joker f+f that a mate gave me for free, only need a new wheels and tyre, but ive gone and changed all the parts. Plan is to just use it as a cruser to get me onto campus, then buy another to learn on.

So i have a prism 3pce crank and an exposure 44 tooth chainwheel. (only buying cheap bits to start off with)

Problem is i dont have a clue how to fit the crank.
Ive alredy mounted the bearing cups in the frame.

these are the parts i have....

theres also a small adapter with the chainwheel. (but it wont fit onto the crank with it)

Any help would be great..... the simpilar the explanation the better..lol

cheers
bailey

stidds · « **Reply #1 on:** April 10, 2008, 02:16 PM »

Ok here goes:

1st ignore the small adapter (top had washer), you won't need it with this chainring.

As the cups are in next would be the bearings in the cups, then you have the thin dust covers (big black discs under above the bearing on the right in the picture and below the bearing on the left).

Now put the axle through the bottom bracket. Now you have to put the threaded nuts (top right and bottom left in the picture)on the crank axle, easy to know which is which as they have different size threads so they can only go on one side. If you look at the nuts they both have 1 side that looks the same, this side is fitted against the bearings and bearing dust covers. Lastly you have the toothed washer and lock nut, these go on the same side and once again will only screw onto one side of the axle.

So basically you have to do one side at a time otherwise you will not be able to put the axle through the bottom bracket and also you will find that the bearings keep falling out.

Remember to grease the bearings 1st.

perry · « **Reply #2 on:** April 10, 2008, 02:23 PM »

todays how to is brought to you with the magic of paint

to start with i havnt numbered the seals , im not a believer in trying to seal caged bearings , id rather whip it apart to give it a proper clean

does 2 fit onto 1 without too much of a gap

about a mill should be fine ( 9 shouldnt be needed here , its an adapter for smaller number 1s )

get the right hand crank arm and slide it on to the right hand side of number 1 as viewed in the pic , that way you can get the orientation right for the bolt that holds the arm to number 2

put the bolt in ( its not shown but it will be needed otherwise pedalling wont move number 2 )

screw number 3 on , from memory its right hand thread , dont do it too tight , just finger tight for now , well do it dry ( without grease ) first

take a number 4 and place in the instaled cups in the frame ( ball side first ) itl be obvious if its the wrong way around

pop the lot on

put the other number 4 in the other side and screw number 5 on ( might be left hand thread )

next is number 6

then 7

lastly 8

does number 2 touch the chainstay at all ? does it look correct ?

if your happy with it take it apart as far as number 3 and tighten with a hammer and drift ( flat screwdriver ) slather the bearings in grease , maybe some on the middle of number 1 to ward off corrosion , some on the threads is ok , youl notice it screws together easier as the the threads were chassed while doing it dry

5 is the preload and 8 is the lock nut , slightly on the tight side is good as itl settle in and should be just about right , but getting it right is down to feel so expect to tighten/loosen these a few times

stidds · « **Reply #3 on:** April 10, 2008, 02:27 PM »

Good work Perry, you have got too much time on your hands mate.

perry · « **Reply #4 on:** April 10, 2008, 02:30 PM »

tell me about it

i was mid sandwich and thought , shall i number them

makes explaining much easier in the long run

you often dont know if your explaining to an engineer who just hasnt done it before or a granny whos never seen a spanner

bai13y · « **Reply #5 on:** April 10, 2008, 02:37 PM »

cheers perry,

thats great, i'll start now and let you know how it goes.

does 2 (chainwheel) go on the left or right side of the shoulder of 1,

cheers

bai13y · « **Reply #6 on:** April 10, 2008, 02:39 PM »

Quote from: perry on April 10, 2008, 02:30 PM

tell me about it

i was mid sandwich and thought , shall i number them makes explaining much easier in the long run

you often dont know if your explaining to an engineer who just hasnt done it before or a granny whos never seen a spanner

***Im an engineer...just never done this before.
but thanks for all the help!!

perry · « **Reply #7 on:** April 10, 2008, 02:42 PM »

i wrote it to go on the left ( 1piece style but i might be wrong $:-\$ ) its been a long time since i had my hands on that style of 3 piece

it would depend on the chainline

edit ; cool , as with most things in your line of work deduct and cancel out what seems wrong

perry · « **Reply #8 on:** April 10, 2008, 02:52 PM »

after looking at the spindle closely it would seem as the chainring goes on like a 1 piece as i said as the thread for number 3 doesnt go to the end ( without the ring it might not tighten down against the edge )

are you studying engineering at the moment ? or about to . what course is it ?

oh and hello , welcome to the mad house

bai13y · « **Reply #9 on:** April 10, 2008, 03:17 PM »

Quote from: perry on April 10, 2008, 02:52 PM

after looking at the spindle closely it would seem as the chainring goes on like a 1 piece as i said as the thread for number 3 doesnt go to the end ( without the ring it might not tighten down against the edge )

are you studying engineering at the moment ? or about to . what course is it ?

oh and hello , welcome to the mad house

Ye i think i got it cheers.

Im in m final yr at loughborough uni studying Automotive eng (cars)

The BMX is a new toy, stop me spending thousands on my car, i'll spend hundreds on a bike lol.
plus theres more freedom to play with the bike then there is my car...untill i buy a 2nd lol)

Should probably itroduce myself properly somewhere,
really like the forum, its a good read/ insite into the propper world of bmx.

cheers

stidds · « **Reply #10 on:** April 10, 2008, 03:20 PM »

Quote from: bai13y on April 10, 2008, 03:17 PM

Should probably itroduce myself properly somewhere,

Get over to the Welcome section at the top of the forum, introduce yourself and get the virtual beers in.

perry · « **Reply #11 on:** April 10, 2008, 03:44 PM »

cool

i thought about doing automotive but as im sure you know its a very saturated area , all the kids want to build race cars

and as i prefer a more traditional aproach vvvvv its an area thats getting outdated

with a bit of luck i hope to do a maufacturing engineering btec in sept

bai13y · « **Reply #12 on:** April 10, 2008, 03:57 PM »

sounds good,
Ye i know what you mean, my year is split into F1 nuts, familey hatchback designers, modifiers-not chav boy racers-but wanna do performance stuff) and people that really dont care and just want a degree.

I'm one of those modifiers, i wanna go into say track car building or BTCC and GT cars.
Where you gonna be studying?

Another Bike Q,
What type of Brake cables when using a gyro?
and how do you fit them when the brake at the back is like this...

(bike no longer looks like this....but this is how i got it)

cheers

perry · « **Reply #13 on:** April 10, 2008, 04:26 PM »

itl only be a year course and luckily its only 5 mins away

although i can only do it if i manage to get a job to get some pennys before sept

normal gyro cables will be fine for that

http://www.alansbmx.com/product_info.php?cPath=32_55&products_id=3013

http://www.alansbmx.com/product_info.php?cPath=32_55&products_id=3014

looks like you have a hole in your seattube ? put a threaded adjuster in and run the cable through it

then a brake bridge , doesnt have to be as fancy as this

http://www.alansbmx.com/product_info.php?cPath=32_55&products_id=4240

then a stradle wire for the actual u brake

do you realllly need a gyro ?

dj_benice · « **Reply #14 on:** April 10, 2008, 04:59 PM »

Quote from: bai13y on April 10, 2008, 03:57 PM

sounds good,
Ye i know what you mean, my year is split into F1 nuts, familey hatchback designers, modifiers-not chav boy racers-but wanna do performance stuff) and people that really dont care and just want a degree.

I'm one of those modifiers, i wanna go into say track car building or BTCC and GT cars.
Where you gonna be studying?

Another Bike Q,
What type of Brake cables when using a gyro?
and how do you fit them when the brake at the back is like this...

(bike no longer looks like this....but this is how i got it)

cheers

Speak to keep it lit, you wanna see the jaws hit the deck when impatient m3 drivers flash him to move over and then when he does and guns it they get destroyed by a corrado

bai13y · « **Reply #15 on:** April 10, 2008, 06:11 PM »

Quote from: dj_benice on April 10, 2008, 04:59 PM

Speak to keep it lit, you wanna see the jaws hit the deck when impatient m3 drivers flash him to move over and then when he does and guns it they get destroyed by a corrado

haha ye i will, i own a vw golf g60 rallye.....

dj_benice · « **Reply #16 on:** April 10, 2008, 08:42 PM »

nice motors, type moonracing into youtube to see ade (keep it lits) mk1, about 270 bhp if I remember rightly n weighs 850kilos, dales should be finished soon gonna be pumpin out just over 500bhp per tonne which is veyron territory for a 50th of the money

bai13y · « **Reply #17 on:** April 10, 2008, 09:01 PM »

Quote from: dj_benice on April 10, 2008, 08:42 PM

nice motors, type moonracing into youtube to see ade (keep it lits) mk1, about 270 bhp if I remember rightly n weighs 850kilos, dales should be finished soon gonna be pumpin out just over 500bhp per tonne which is veyron territory for a 50th of the money

dale...as in owned a 20vT rado and mk1 and is now building a g60 sycro 20vT??? lol

I've met him, go to a couple of vw meets he's at, and his build thread is on edition38.
I'll look on youtube.

dj_benice · « **Reply #18 on:** April 10, 2008, 09:11 PM »

Quote from: bai13y on April 10, 2008, 09:01 PM

Quote from: dj_benice on April 10, 2008, 08:42 PM
nice motors, type moonracing into youtube to see ade (keep it lits) mk1, about 270 bhp if I remember rightly n weighs 850kilos, dales should be finished soon gonna be pumpin out just over 500bhp per tonne which is veyron territory for a 50th of the money

dale...as in owned a 20vT rado and mk1 and is now building a g60 sycro 20vT??? lol
I've met him, go to a couple of vw meets he's at, and his build thread is on edition38.
I'll look on youtube.

Coolio you going the qtr mile on sunday dale will be there and I might join him unless I can get up to the hills then its boarding all the way

bai13y · « **Reply #19 on:** April 10, 2008, 09:53 PM »

Quote from: dj_benice on April 10, 2008, 09:11 PM

Coolio you going the qtr mile on sunday dale will be there and I might join him unless I can get up to the hills then its boarding all the way

ye i think so getting a lift up wit my mate, he's on the clubseat stand.

dj_benice · « **Reply #20 on:** April 10, 2008, 09:56 PM »

Quote from: bai13y on April 10, 2008, 09:53 PM

Quote from: dj_benice on April 10, 2008, 09:11 PM

Coolio you going the qtr mile on sunday dale will be there and I might join him unless I can get up to the hills then its boarding all the way

ye i think so getting a lift up wit my mate, he's on the clubseat stand.

If I make it there will give you a shout, might take me bmx n see what I can clock the quarter in, anyone else up for it on 20"ers

lazychubs · « **Reply #21 on:** April 10, 2008, 11:11 PM »

the best one was one of me mate paul knight from the vw mag
type 25 with fly by wire audi a8 turbo deisel
flashing a boxster to move over at +150 mph to move over lol