Freewheel crank resources

Hi,

Miles said:
recumpence said:
One thing I am kind of green on is, I know there are two thread sizes (diameters) on BMX hubs. I know the larger side is the most common. Is the larger thread what we are looking for? Is the smallest tooth count freewheel for our purposes 11 tooth?

11t? You used to be able to get 12t freewheels for the BMX metric thread but I think the smallest now is the Odyssey 13t.

The smallest freewheel for ISO standard thread is the AC Racing 15t.

One thing to bear in mind is that BMX has mostly gone over to cassette now, so we don't know for how much longer the smaller thread freewheels will be readily available. Anyway, at the moment, the Odyssey is a good choice - it's available LHD, too.

I think the best solution would be to modify Surly 13t cogs to fit on White FW's using an adaptor. I bet Jason would make some adapters and modify some cogs for under $20 per set. That would be the the strongest FW with a strong 13t sprocket. I'm not sure if it would be easier to modify cassette cogs or track cogs. I think I'd use track cogs because they are available with 1/8" tooth thicknesses.


Track cog:
http://www.treefortbikes.com/121_333222337776__Track-Cog-1-8-13-16-Tooth.html
imgDsp.aspx

Like our cassette-splined cogs, these are made from machined, heat-treated and chrome plated SCM415 CroMoly steel, so they are tough and long lasting. Track cogs are available in either 3/32" or 1/8" tooth thicknesses and in every size from 13-22t.

Cassette Cog:
http://www.treefortbikes.com/91_333222338203__Single-Speed-Cassette-Cog.html
imgDsp.aspx

Our cogs will work with 6-9-speed 3/32" chains, although we recommend the inherently updated quality of an 8 or 9 speed chain. They are also available in every increment from 13-22t, so you can select that perfect gear.
 
GGoodrum said:
I'll probably try doing this, just to have somethig to test, but the "permanent" solution for me is still to use Matt's unit, which is a much more elegant design and doesn't take up any more space.

I still think a two-stage version of Matt's unit, "unfloded", will easily fit behind your seatpost.

Hi Gary,

totally agreed on matts gb, but i dont see how you envisage it fitting folded out without interfering with my suspension?
9" i think matt said,(resist the gag) i have about 6" at best?(resist again!!).
i did consider having the motor fitted just below the seat and the gb unfolded downward through the suspension but it got very tricky to work out,also i would still have an issue with how to encase the gb so that all moving parts are encased/covered?

Cheers,


D
 
deecanio said:
Hi Gary,

totally agreed on matts gb, but i dont see how you envisage it fitting folded out without interfering with my suspension?
9" i think matt said,(resist the gag) i have about 6" at best?(resist again!!).

Sorry to hear of your shortcomings (sorry, you really didn't expect anyone in this crowd let that pass, did you?? :mrgreen: ), but I guess you will need to do something unique. Maybe you could still use Matt's "unit", but just not unfolded all the way (semi-erect??)?

deecanio said:
i did consider having the motor fitted just below the seat and the gb unfolded downward through the suspension but it got very tricky to work out,also i would still have an issue with how to encase the gb so that all moving parts are encased/covered?


It would be a shame to cover up all of Matt's "glory", especially if it's just for esthetics. If you are talking about shielding from the elements, however, I would agree, covered would be desirable, especially if you are using an outrunner, with a spinning can.

-- Gary
 
Hi Gary,

a semi wouldn't fit properly either im afraid, i need rigid for the box :roll:
ok enough.

Am i the only one who is worried about high rpm belts/chains/sprockets exposed??
it's not so much asthetics, although that has some part to play for sure, but safety? i can just see someone getting there jeans caught in the gb and ending up on the deck bike still firmly attached to clothing :shock: no else sees this as a potential issue,really? on the recumbant its not an issue but for downtube mount??
I think your right though, a special needed indeed,i really like the hacker box you have, thats how i want mine if i can't fit matts gb as is - i'll have another look once matt posts up a full assembly as i may get away with it but if not i'll have to get a box made just for the job :cry: if thats the case i'll have to plan it better once i get my bike home and then ask matt to build or send me the parts and ill have it built here in blighty.


Cheers,

D
 
deecanio said:
Am i the only one who is worried about high rpm belts/chains/sprockets exposed??
I managed to get my jeans caught in my bottom bracket drive powered by a wimpish MY1018. Very scary, although my sons thought it was hilarious watching their dad being eaten alive by his ebike.
I'd hate to think what damage (or entertainment) a Plettenberg could dish out...
 
Exactly Malc.

no one else worried????
 
There are a huge number of items to be considered for a production system or entire bike. For a high-end limited production drive requiring some custom work to install, I would not think making guards is a concern for most people. This is not a turn-key setup. Kind of like buying a custom street-rod with concerns about no airbag. :D

I haven't run a chain guard since I was a kid and I haven't gotten my pants caught since being a kid. Also, the drive components will be farther away from your pant leg than the crank sprocket.

I am not saying it is not a concern, I am just trying to make the drive by itself. Guards and/or any other items that are specific to each bike will be left to the bike owner to fabricate. :wink:

A pant leg guard is a simple thing to make. Completely enclosing the drive is another story. I think that would be alot harder.

Matt
 
You know, with the Hacker/gear setup, I did worry a bit about getting tangled in the spinning bits, but I think what worried me the most was the chain to the crank. The Cyclone setup has cured me from worrying about the chain. The area where I'm planning to mount Matt's single-stage unit, with the Hacker, is behind the seat post, so I'm not so worried about this issue. I'm also not too worried about the "elements", as that really isn't a problem here, where we live in drought conditions 4 out of 5 years.
 
Getting back to the issue of the crank FW mod., I've been trying to find what the largest chainring is available for the 110mm BCD used by the Big Cheese adapter. It seems 50T is pretty easy to get, but I thought I saw one somewhere that was larger, like 54 or 55T. I want to go as big as I can, as I plan to use a 12T track cog on one of these new freewheel adapters, on the output shaft. Anybody know a good source for large chainrings that will still fit the 110mm BCD?
 
GGoodrum said:
Anybody know a good source for large chainrings that will still fit the 110mm BCD?

80t big enough (at a price..)? :mrgreen:
http://www.greenspeed.com.au/gsparts.html

More reasonably for 130mm BCD:
http://www.dutchbikes.nl/uk.htm (under "Recumbent Parts")

62t for 130mm BCD here:
http://www.easystreetrecumbents.com/stuff/chainrings.html
 
Wow, 80T is pretty damn big! :mrgreen:

It needs to have a 110mm BCD, in order to match the Big Cheese adapter. I'm not sure why there are so many BCD "standards", but it sure makes it harder to find what you are looking for, that's for sure.
 
http://www.chickencycles.co.uk/index.php?cat=32&ord=2 (scroll down to TA Zephyr)

The Zephyr chainset has been discontinued but there may still be chainrings out there....
Ed. 58t, here: http://www.peterwhitecycles.com/zephyr.asp
 
Hi,

Malcolm said:
deecanio said:
Am i the only one who is worried about high rpm belts/chains/sprockets exposed??
I managed to get my jeans caught in my bottom bracket drive powered by a wimpish MY1018. Very scary, although my sons thought it was hilarious watching their dad being eaten alive by his ebike.
I'd hate to think what damage (or entertainment) a Plettenberg could dish out...

Miles said:
You guys don't wear trouser clips? :)

Certainly it's something I'd take into consideration if I was converting a bike for someone else.

recumpence said:
I haven't run a chain guard since I was a kid and I haven't gotten my pants caught since being a kid. Also, the drive components will be farther away from your pant leg than the crank sprocket.
Matt

I'm firmly with D and Malcom on this.

  • Belt and chain are running at a much higher speed than pedaling.
    Belt and chain are running with a lot more power.
    Its almost impossible to imagine a scenario where something is caught in a chain and you continue to pedal. On the other hand its pretty easy for the motor continue to apply power with something caught in a chain or belt.

    Also what about falling or bumping into obstacles that push your leg against a chain or belt. (Not unlikely for D). Could go through your leg almost like a chain saw.

recumpence said:
I am not saying it is not a concern, I am just trying to make the drive by itself. Guards and/or any other items that are specific to each bike will be left to the bike owner to fabricate.

A pant leg guard is a simple thing to make. Completely enclosing the drive is another story. I think that would be alot harder.

Matt

But I also agree with Matt that I think its Ok to leave this for the end user, although some inexpensive chain guards wouldn't be a bad idea.
 
Hi Mitch,

indeed, we can't expect matt to fit chainguards and all manor of other maybes that may or may not be needed for each individual bike, i was only saying because i think it is a very important safety point, not meant in any way to reflect the quality or design of matts fantastic drive.
i found it strange that no one had mentioned it previously??
I would want it all covered up as a minimal requirement personally but if its mounted out of the way maybe it won't even be an issue?
Still as long as long as we are all aware, wouldn't want any of us to end up with injury through naivity :shock:


Cheers<

D
 
i dont know what lexan is but im guessing you can still *see* inside? :) that would look real nice 8)
unfortunately for me i HAVE to hide my drive for stealth reasons so i'd have someone make pear shaped cover plates that just cover the pulleys belts and chains but leave the bodys on show.

D
 
thanks TD, stop teasing me matt ,i know your building your mtb night and day on the side and already have ar polycarbonate covers :mrgreen: come on, show me!!

D
 
Hi all,

whilst doing some looking around at the needed parts for our respective setups i found this on the echo freewheel cranks....
http://biketrials.com/review/2004_Echo_Stock_Front_Freewheel_Cranks_L401.html
just for info.
i read a few trials forum posts and these seem a better freewheel arm maybe? there the ZOO ones about 6 pics down...
http://www.thetrialsinshop.com/drivetrain.html
must do some more reading about trials, seems they have nice kit that would benefit us.

Cheers,

D
 
Back
Top