Freewheel crank resources

[recumpence]

You probably got the last set of 170mm black cranks didn't you? I had to settle for silver. :wink:

Matt

 

[GGoodrum]

Apparently, they are still available at this price, as I was able to place an order. It says I have to wait for a shipping quotation, though. I'm still trying to see what the price difference will be, from ordering these at WebCyclery ($165 plus shipping...), and to see if we get a refund on the VAT, which I think is something outrageous, like 17 or 18% in the UK.

 

[J Barrie Wilkinson]

For those of you on a limited budget that find the price of these trials cranks very high and do not mind using older technology square taper cranks, they are available at much lower prices and also lower quality from Jim Olsen at Cyclone USA http://www.cyclone-usa.com/store.php?crn=203 for $46 plus shipping. I have an Ebike with a PowerPack motor driving a # 25 chain to a 90t sprocket bolted on a Vision freewheeling crank. I needed to replace the threaded crank after a crash that bent it and searches for Vision crank parts were useless. Jim got the crank to me quickly and in good shape.
Barrie

 

[Miles]

You probably got the last set of 170mm black cranks didn't you? I had to settle for silver. :wink:
Matt

Wasn't me guv.... I ordered 160mm black 8)

 

[deecanio]

Hi All,

what did i miss???
all sold out!!!! wtf??
j/k - i posted that forum thread as a fairamount of ppl have had the echo crank freewheel threads strip???
i was suggesting another brand?


Cheers,

D

 

[Miles]

i posted that forum thread as a fairamount of ppl have had the echo crank freewheel threads strip???
i was suggesting another brand?

D,

I doubt that thread stripping has much to do with brands... 7075 alloy is stronger than 6061, though...

 

[recumpence]

7075 is spuper strong! Also, the threads would only strip in trials use, if ever. In our application, threads will see little load in comparison.

I tried to complete my order this morning. The discounted amount in my cart is 61. However, the checkout is asking me for 80. Hmm, I am waiting to see how they answer my email about that. :?

Matt

 

[deecanio]

Hi Guys,

ahhh i see, my bad, sorry i thought i might be saving us from a bad investment
so were the stripping ones in the thread a different grade of ally? meh you guys know what your doing.
I'll see if there's any left (mumble moan mumble)

Gary UK VAT is currently 15% i believe, robbery.
i posted then went to bed and missed the boat
dammit back to 92 squids!!! oooohhhh blue cranks!!!!! 8)


cheers,

D

 

[Miles]

The trials guys break chains, cranks, freewheels...... as Matt says, it's unlikely this would be a problem for us..

 

[deecanio]

ok cool.


Those cranks at tartybikes were on limited offer Miles?


D

 

[Miles]

so were the stripping ones in the thread a different grade of ally? meh you guys know what your doing.
D

The ones in the review you linked to were the Echo forged 6061 cranks that Malcolm and I are using. The ones which were reduced at Tarty yesterday were machined 7075.

Try ringing up Adam at Tarty and say there was a problem and the order didn't go through :lol:

http://www.youtube.com/watch?v=7DBOsvSFvuI

 

[deecanio]

thanks Miles,

although i didn't see any square taper option??
i have the 127mm bb for taper and also a lot of crank spares so i dont really want to change to ISIS bb.

Cheers,

D

 

[Miles]

ISIS only, I'm afraid - that's why I got the forged ones for my 1st project. There's not so much choice in square taper.

If 160mm is ok, these have a nice brass thread
http://www.tartybikes.co.uk/product.php?product_id=10663&category_id=11

These are available in sq. taper:
http://www.tartybikes.co.uk/product.php?product_id=10467&category_id=11

 

[deecanio]

thansk Miles,

maybe i'll have a nosey around seems like there's quite a few to choose from, i do like those blue ones though, nice.
a feck it maybe i'll swap to ISIS so i can have the blue, we'll see.
I am also considering going with Gary's hacker too (which model is it Gary?) - conditions being it can handle 5kw and its as well supported as the pletty? reason being i would like to use single stage reduction and the hacker has a kv of 148 i believe, we'll see.
Miles, if i used the Hacker and could get away with single stage do you think i could use belt to connect from gb output to crank?


Cheers,

D

 

[Miles]

Miles, if i used the Hacker and could get away with single stage do you think i could use belt to connect from gb output to crank?

You might have to use this: http://www.gates.com/brochure.cfm?brochure=7468&location_id=11347

If you let me know the power, the required reduction ratio from the G.B. to the crank and the speed at the driver sprocket (G.B. output), I'll see what's possible.

 

[deecanio]

Hi Miles,

i'll get some more info from Gary on his hacker and also i'll ask matt if he has any other opinions on motor. reducing the kv rating is greatbut i dont want to run anything that can't run 5kw well.
I think the pletty is a fine motor but if i can get away with a single reduction and belt to the crank that would be the dream ticket.
I'll some more looking and come back to you, thanks for the help

Cheers,

D

 

[GGoodrum]

thansk Miles,

maybe i'll have a nosey around seems like there's quite a few to choose from, i do like those blue ones though, nice.
a feck it maybe i'll swap to ISIS so i can have the blue, we'll see.
I am also considering going with Gary's hacker too (which model is it Gary?) - conditions being it can handle 5kw and its as well supported as the pletty? reason being i would like to use single stage reduction and the hacker has a kv of 148 i believe, we'll see.
Miles, if i used the Hacker and could get away with single stage do you think i could use belt to connect from gb output to crank?


Cheers,

D

The model I have is the A60-18L. The kV is 149, and the retail price over here is $270. The specs are here. It lists a peak power of 2600W, but that's really underated, in my opinion. In an RC plane, the "peaks" are really more sustained than we are likely to see on an ebike. For the few short times I tried it, the motor never got hot.

They now have an A80 model, but the mounting is weird, like the A100/200s, and the price is a ton higher. I like the Hackers because the quality is much better than most of the stuff that comes from China. Tha Hackers are assembled in China, but the steel used in the stators and the magnets are of a higher quality.

I got some HTD sprockets and belts in from STP-SI yesterday, so I'm going to try updating my box setup this weekend, and do some testing.

-- Gary

 

[Miles]

Sounds like a 50:1 reduction is needed overall (to the cranks). That would need a very large intermediate pulley, to do it with a single step G.B.

 

[deecanio]

Thanks Gary,

i'll watch with interest this weekend and look at the motor when i get home.
50-1 is better than 80-1 with the pletty?
i could do 6-1 at the box 8-1 at the crank?

Cheers,

D

 

[Miles]

i could do 6-1 at the box 8-1 at the crank?

For belt, only if you could handle a pulley at the cranks over 400mm in dia. ...... 8)

I think 2 stage gearbox is more realistic.....

 

[deecanio]

400mm is a fair size but 200mm is easily hidden with a 42t chainring?
i fancy doing an all belt setup to crank, i could use the belt matts using for stage 1 (maybe 2?) but then i need something stronger for the 3rd (maybe second too) - do you think that could be done Miles, assuming dual stage?



cheers,

D

 

[Miles]

Probably, but bear in mind that 3 belts will take it's toll on efficiency...

How about using this for the final stage: http://www.g-boxx.com/pdf/Gates/GATES-Carbondrive08.pdf ? You can buy the lightweight pulley-rings from stock, then... Belt lengths might be a problem, though...

 

[Miles]

Maybe see how David gets on with this? http://www.cycledrive.com/home.html

 

[deecanio]

hi Miles,

those belts look nice, i dont seem to be able to browse the pulleys for them though, do i need to be a business and sign up to view the catalouge?
that drive is nice too but i only want to belt to the crank as i want to keep the standard chain and gears.
if i used that second drive i'd need a geared hub and i dont think there up to off roading and getting slammed, thats why im set on having a totally standard rear wheel and normal chain and gears.
how much efficiency loss are we talking about across 3 belts as oposed to say three chains? if its reasonably small it wouldn't matter enough to put me off i dont think?
mmm, how would i make the belt to crank freewheel?

cheers,

D

 

[Miles]

I was thinking you could use Cycledrive parts for the G.B. to crank stage - they're standard 8mm pitch so you could easily get shorter belts.

Probably about 5 to 6% loss per stage for belts and around 3% for chain, though they don't compare easily.