(ORBO) MasterSports/CyclePro (HEATSINK DONE AND FITTED!)

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Just finished up 'Hot rodding' my KT coaster brake hub for the back of this, check the thread here for a cool video if you want to do the same:
http://www.ratrodbikes.com/forum/in...-rodding-your-cb-hub-for-klunking-duty.93356/

I was going to swap in a Shimano B series guts, but apparently the B series is a bit different to the E series the KT is based on, so I just modified the KT guts.

Shimano and KT comparison, you can see the much smaller clutch and brake shoes on the Shimano B series.

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You can see in that photo above, not only did I chamfer the front of the brake shoes as recommended in the video, but as the KT shoes have grooves across them instead of around them , I decided some diagonal grooves may help the grease to stay on the shoes longer and spread around the braking surface, I don't know if it will work, but it has to be worth a try! :thumbsup: I will say that those brake shoes are definitely not mild steel, you can tell by the sparks when grinding on them.

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Started re-assembly:

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The video recommends 15 balls in the inner driver and 10 in the outer driver, I found that to be too many to fit correctly, not sure if that is because mine is a KT and not a Shimano, @Bicycle808 has said something similar in the past...

Here is the inner with 15, you can see they don't all fit:

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Removed one and then screwed the driver back in:

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Only 9 balls in the outer:

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My wife decided to get a happy snap:

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Hub finished:

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I did manage to fit the much nicer Shimano brake reaction arm on to the KT hub, no more 'Sidewalk use only' warning!

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First time I have ever rebuilt or modified a Coaster Brake hub, went pretty well!
The hub seems much nicer to use now, very smooth, nice positive engagement with only a small amount of turn between drive and brake, can't wait to try it out!

Thanks to @Bicycle808 for sharing that video, never would have tried it without it!

Luke.
 
You know what happens next when you rebuild your Coaster brake hub? You need to lace it into a rim!

Going back to the '80's and '90's with this wheelset!

Araya 7X rims,
Sunshine high flange front hub.
Coaster rear hub,
Proper fat and knobby 26" gum walls!

This would have been my ultimate wheelset back in high school!

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:banana:

Time to relive my youth when this bike is done! I didn't even polish the rims while I had them out, and I re-used the old spokes, really want this to appear like a true survivor from back in the day...

Luke.
 
Love the fat and knobby gum walls! I am going to have to watch that coaster hub rebuild vid one of these days.
 
You know what happens next when you rebuild your Coaster brake hub? You need to lace it into a rim!

Going back to the '80's and '90's with this wheelset!

Araya 7X rims,
Sunshine high flange front hub.
Coaster rear hub,
Proper fat and knobby 26" gum walls!

This would have been my ultimate wheelset back in high school!

View attachment 15471

View attachment 15470

:banana:

Time to relive my youth when this bike is done! I didn't even polish the rims while I had them out, and I re-used the old spokes, really want this to appear like a true survivor from back in the day...

Luke.
Gotta be careful reliving youth Luke, we're not as resilient as we once were.
But man it sure is fun.
 
Gotta be careful reliving youth Luke, we're not as resilient as we once were.
But man it sure is fun.
Yeah I lean't that with the swingbike... :blackeye:
I used to crash my BMX, rip half my skin off on gravel rash and just pick the bike up and keep riding, sometimes doing the exact same thing again...

Now I come off I have to lie there for 15 minutes to catch my breath, untangle myself and sit down another 30 minutes before hobbling home leaning on the bike... :21:

Luke.
 
A block of 1/2" thick Aluminium arrived today...

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Spent some time cutting pieces out:

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And then some more sanding things to shape:

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Next step is to break out the drill and holesaws, throw some parts on the lathe to get the exactly the right size and tap some 5mm threads...

Is it becoming clear yet what I am attempting to build? :39:

Luke.
 
Close! :thumbsup:

I have been following 'Coaster Culture' on their website and Facebook page, waiting for them to make a particular item available, even though I know shipping would probably put it out of my price range anyway... I am thinking that they may be having trouble making their product commercially available at a reasonable price due to the huge amount of machining involved...

I decided to build my own... Unfortunately my little hobby lathe only spins a max of 3", so I had to change the design a bit, if it works as intended I am thinking I will send them the drawings and pics, as this design could probably be mostly cut on a waterjet and only require minimal lathe work, dropping the cost per unit price considerably. :thumbsup:

It is a Coaster brake heatsink!

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I imagine mine would not be quite as efficient as theirs, but it should still be much better than not having one! I can tell you that this aluminium transfers heat really well, I noticed it quite a bit while cutting and sanding...

Luke.
 
Had a bike building session with @kelvin hahnel today, when we finished on his we decided to throw the old girl together and take it for spin!

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Going to switch to a layback post and I have another seat out getting wrapped in new leather for it, but it is a great rider and already more comfortable than most modern bikes!

The wheelset is awesome, the modified hub is easily the best coaster I have ever used, great modulation range before lock-up, quick and positive engagement and a very small rotation from full forward to full back, the Arayas are lighter than the original rims and those fat gum walls suit perfectly!

The frame has great geometry for cruising and is still short enough to throw around, surprisingly light all up too!

Very happy!

Now to just strip it all back down and clearcoat the original paint, throw the layback and new seat on it and it is done... Aside from the heatsink of course! ;)

Luke.
 

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