7 Speed Freewheel with 11 tooth cog for Magic Pie. (A How To guide) :-))

[Andrew]

Yes,  they are the 'big apple tyres', or ballon tyres as they are also called.  it's funny that you mention them as i've just changed them.
 No. 1 ,  the suspension balloon affect of the tyre is redundant as they are pumped up to beyond 40psi.
 No.2  ,   feel good in the dry but do not instill much confidence taking fast corners in the wet. i.e going straight through fast roundabouts.
 No.3 ,  I had a nightmare taking one off a wheel and the rubber edge split and exposed the metal wire edge (probably my heavy handedness)  but now it is unuseable.

I'm now about to try these - http://www.chainreactioncycles.com/Models.aspx?ModelID=24632

'Wrap around tread'  if they are good on a smooth half pipe ramp, they should be good on the road.

i believe 'Bike Mad' aka Alan,  has them on his mountain e-bike.  the price above on chainreaction cycles is by far the cheapest you'll find them for and it includes very quick free delivery

Andrew

[Andrew]

also, these could be really cool. wrap 'round tread with little rolling resistance http://www.chainreactioncycles.com/Models.aspx?ModelID=5847

[DirtyGinge]

Thanks andrew...please let me know how you get on

p.s. dual pies installed now....OMG...you are in for a treat there my friend, just one caution, hold on to the handlebars tight when you first full accelerate, I kid you not, you will fly off !!!! after first ride, check the spokes, I had a couple work loose

[gf3]

isn't there an cog with 11 tooth that is 6 speed?

Not that I've seen, I think even 12t is rare on a 6spd.

Hey Awesome work Andrew!! Great stuff you took some pics and posted it up, I was thinking with the washers - was cool but have you got some holding your axle in the dropouts now? I'm sure it's tight, but you don't want all that hard work you've done to 'spin' on you!

The guy at my local bicycle store is possibly the most unhelpful person alive lol, I'm sure there are many others that may have a suitable axle spacer. I had a quick squiz at this page: http://www.bicyclepartswholesale.com.au/contents/en-us/d65.html and there may be something there for a quick solution.

Good stuff, I'll pick up one of those now I'm sure it will fit I just received my linear stepper motor I'm building into the rear frame for an electronic gear change should be fun to see if I can get working

I had a look at doing a stepper motor gear change. I made up a test circuit with a 16 bit counter so you press one button to change up an another to change down. using 5 gears on the large chain wheel 6gears on the middle chain gear and then 5 on the smallest chain gear. Had to buy a sun tours free wheel 13t to 18t so the gear ratios wouldn't over lap.

 However I enjoyed getting It to work on a bread board but when I found I only used top gear I abandoned the project. 

[MonkeyMagic]

isn't there an cog with 11 tooth that is 6 speed?

Not that I've seen, I think even 12t is rare on a 6spd.

Hey Awesome work Andrew!! Great stuff you took some pics and posted it up, I was thinking with the washers - was cool but have you got some holding your axle in the dropouts now? I'm sure it's tight, but you don't want all that hard work you've done to 'spin' on you!

The guy at my local bicycle store is possibly the most unhelpful person alive lol, I'm sure there are many others that may have a suitable axle spacer. I had a quick squiz at this page: http://www.bicyclepartswholesale.com.au/contents/en-us/d65.html and there may be something there for a quick solution.

Good stuff, I'll pick up one of those now I'm sure it will fit I just received my linear stepper motor I'm building into the rear frame for an electronic gear change should be fun to see if I can get working

I had a look at doing a stepper motor gear change. I made up a test circuit with a 16 bit counter so you press one button to change up an another to change down. using 5 gears on the large chain wheel 6gears on the middle chain gear and then 5 on the smallest chain gear. Had to buy a sun tours free wheel 13t to 18t so the gear ratios wouldn't over lap.

 However I enjoyed getting It to work on a bread board but when I found I only used top gear I abandoned the project. 

I'm using a servo, and have build a working example. Just need to expoxy it all together and write a small code for a PIC and I'm good to go !!

I removed the big spring in the derailluer and used a metal gear servo. I was going to use a linear actuator, I have a small one but the servo seems to work better.

I'd love to have a chain drive motor and auto gear change based on speed, it would sound awesome lol

[DirtyGinge]

andrew

how are your crazy bobs ?

Ive gone for the big apples...and you know, I didnt get many looks for the dual pies, but many many looks at the big apples

Everyone just keeps saying ( ive never seen anything so big, ( including the wife hehe, but thats another story !!)))

[Andrew]

the crazy bobs don't as yet show any significant wear though I do think they are a much softer compound compared to the apples. I bet the apples last a long time. I had as nightmare removing one of my apple tyres when swaping for the crazies. I used(never again) metal tyre levers instead of plastic ones and they completely destroyed the rubber edge of the apple tyre and now it has the inner wire exposed in several places. I'm not sure if the tyre is still safe to use as the wire could end up pinching the inner tube. I've wondered whether there is a cheap way of getting the tyre edge remolded but it's probably cheaper to buy a new one .  Shame as I was hoping to put both the apples I have on the new bike.

One thing I would say, if these kind of fat tyres aren't pumped up well I would not trust, them around fast bends, for instance, going straight through a round about at full throttle.

Are you using the 'balloon affect' or are they pumped to 40psi?

[gf3]

isn't there an cog with 11 tooth that is 6 speed?

Not that I've seen, I think even 12t is rare on a 6spd.

Hey Awesome work Andrew!! Great stuff you took some pics and posted it up, I was thinking with the washers - was cool but have you got some holding your axle in the dropouts now? I'm sure it's tight, but you don't want all that hard work you've done to 'spin' on you!

The guy at my local bicycle store is possibly the most unhelpful person alive lol, I'm sure there are many others that may have a suitable axle spacer. I had a quick squiz at this page: http://www.bicyclepartswholesale.com.au/contents/en-us/d65.html and there may be something there for a quick solution.

Good stuff, I'll pick up one of those now I'm sure it will fit I just received my linear stepper motor I'm building into the rear frame for an electronic gear change should be fun to see if I can get working

I had a look at doing a stepper motor gear change. I made up a test circuit with a 16 bit counter so you press one button to change up an another to change down. using 5 gears on the large chain wheel 6gears on the middle chain gear and then 5 on the smallest chain gear. Had to buy a sun tours free wheel 13t to 18t so the gear ratios wouldn't over lap.

 However I enjoyed getting It to work on a bread board but when I found I only used top gear I abandoned the project. 

I'm using a servo, and have build a working example. Just need to expoxy it all together and write a small code for a PIC and I'm good to go !!

I removed the big spring in the derailluer and used a metal gear servo. I was going to use a linear actuator, I have a small one but the servo seems to work better.

I'd love to have a chain drive motor and auto gear change based on speed, it would sound awesome lol

You are a head of me there I've never worked with pic chips, and I should have said a 4 bit counter not 16 bit one that counts from 0 to 15. I fed the output into an eprom that I had manually programmed 16 lines of code.
the first 6 bit were for the 6 back cogs and the last 2 bits for the front three with a nor gate to get the third cog. It's funny how when you get all the little leds lighting up as you press the buttons how rewarding it is.   
I also enjoyed using the sound card of my computer as an oscilloscope and finely getting the servos to work with a 556 timer.

but I gave up trying to solder it all together.