Double drilled cranks for a child

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Bensons
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Double drilled cranks for a child

Postby Bensons » 14 Sep 2015, 7:11pm

We have just bought a 2013 Galaxy Tandem.

The cranks are these: Truvativ Firex Front 36T 175mm, rear 48/36/26T 170mm.

We want to change the cranks to double drilled ones for a child. The Thorn ones might work but we will have to change the bb and chain wheels.

If anyone can think of another way to make this work we would be grateful.

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meic
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Re: Double drilled cranks for a child

Postby meic » 14 Sep 2015, 7:19pm

Another option is crank shorteners.
Yma o Hyd

Bensons
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Re: Double drilled cranks for a child

Postby Bensons » 14 Sep 2015, 8:13pm

Thank you, we didn't know about those until now. The Thorn ones don't work with the bike spec we have but we think that the ones from Highpath will work.

Thanks very much.

drossall
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Re: Double drilled cranks for a child

Postby drossall » 14 Sep 2015, 8:48pm

For a smaller child, of course, you want kiddycranks, also available from SJS.

Bensons
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Re: Double drilled cranks for a child

Postby Bensons » 14 Sep 2015, 8:55pm

Shes not that small :). Lovely idea though, we never considered a tandem until now as she would have got bored on long distances.

She is 9 and probably only needs an inch at the most - almost 5ft but we bought the large size Galaxy after trying her on it because it is so close and I can use it too!

We have just bought this as her new bike - size wise we really don't need much adjustment but definitely need some.

http://www.ebay.co.uk/itm/291557500022? ... EBIDX%3AIT.

drossall
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Re: Double drilled cranks for a child

Postby drossall » 14 Sep 2015, 9:25pm

You can gain almost an inch by using an old-style basic seat pin and inverting the clip, so that the clip sits above the saddle rails instead of below.

Probably a better approach than my Dad's; he got me on my first bike by putting wooden blocks on the pedals. I came to no harm, but I cannot recommend this procedure.

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[XAP]Bob
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Re: Double drilled cranks for a child

Postby [XAP]Bob » 14 Sep 2015, 9:35pm

drossall wrote:You can gain almost an inch by using an old-style basic seat pin and inverting the clip, so that the clip sits above the saddle rails instead of below.

Probably a better approach than my Dad's; he got me on my first bike by putting wooden blocks on the pedals. I came to no harm, but I cannot recommend this procedure.


On a tandem that's probably acceptable, the stokid doesn't have to touch the floor to balance in the same way as they would on a solo.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
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drossall
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Re: Double drilled cranks for a child

Postby drossall » 14 Sep 2015, 9:48pm

Good point. That is, after all, the principle behind both crank shorteners and kiddycranks.

Bensons
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Re: Double drilled cranks for a child

Postby Bensons » 14 Sep 2015, 9:57pm

My husband loves your idea Drossall, thank you. It is so close we hope your idea works. I replaced the toe clips on my galaxy recently (must have been 20 years old). Because she is almost there height wise and will be secure in her position on the back we almost think that your seat idea and my old toe clips for a bit of foot stability might do the trick.

I will report back, we are having the delivery delayed until next week when we can both be here.

Bensons
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Re: Double drilled cranks for a child

Postby Bensons » 14 Sep 2015, 9:58pm

Must add that my husband had blocks of wood too !! But I am not sure we would inflict that on our daughter.

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531colin
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Re: Double drilled cranks for a child

Postby 531colin » 14 Sep 2015, 10:29pm

Highpath also used to do double drilling of cranks....don't know if they still do!........http://highpath.co.uk/crank-shortening/

rjb
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Re: Double drilled cranks for a child

Postby rjb » 14 Sep 2015, 10:52pm

You could use a pair of Bungy cords attached to the front and back pedals to keep the rear pedal always pointing in the right direction. This would mean the rear pedal is always in the correct orientation and doesn't drop down. :wink:
At the last count:- Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin, Raleigh 20, Falcon K2 MTB dropped bar tourer, Longstaff trike conversion on a Falcon corsa. :D

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RickH
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Re: Double drilled cranks for a child

Postby RickH » 15 Sep 2015, 4:31pm

Alternative, but somewhat more expensive, crank shorteners are the Circe ones. that give 3 different effective crank lengths & should fit any cranks. Available from Practical Cycles, & others.

Rick.

Bensons
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Re: Double drilled cranks for a child

Postby Bensons » 15 Sep 2015, 5:44pm

Thank you, we will ask them if they will work if we need them, £50 cheaper than the high path ones.

drossall
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Re: Double drilled cranks for a child

Postby drossall » 15 Sep 2015, 6:48pm