Tadpole using BMX forks

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Oct 4, 2014
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Astoria Oregon
Any particular reason (other than convention) one doesn't see many tadpole builds using a set of BMX front forks, either pivoting Fortrike-style or by building the crossmember to attach to the fork headtubes?

I'm sure there's some weight savings to be had by going the conventional route; however, if you're using caliper brakes you still have to build mounting arms like on the StreetFox, and using the forks would alleviate the need to find wheels with the larger, less common 14mm axle.

Also, obviously, the outboard fork legs are going to count towards whatever your target width is and against your available wheelbase within that target width, but aside from those issues, is there anything else that I'm missing here?
 
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Any particular reason (other than convention) one doesn't see many tadpole builds using a set of BMX front forks, either pivoting Fortrike-style or by building the crossmember to attach to the fork headtubes?
This site is to support Brads plan , and none of his adult trikes are build like that.

Fortrike are a commercial tadpole builder who make their own forks Fortrike

Google will turn up a few like this ? built in that manner also.




I'm sure there's some weight savings to be had by going the conventional route; however, if you're using caliper brakes you still have to build mounting arms like on the StreetFox, and using the forks would alleviate the need to find wheels with the larger, less common 14mm axle.
Can't see where the weight saving is coming from as you are adding a pair of front forks , and BMX forks are very heavy.

Also, obviously, the outboard fork legs are going to count towards whatever your target width is and against your available wheelbase within that target width, but aside from those issues, is there anything else that I'm missing here?
track not wheel base ;)

it is far easier and makes more sense to build a delta using 2 front forks and probably not much heavier , the track problem still exists however that depends where you ride as to whether it is a problem or not being a bit wider and having some hardware on the outside of the wheel ?
 
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Oct 4, 2014
Messages
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Astoria Oregon
I'm aware that none of Brad's trikes are built that way, but Brad also welcomes and encourages creativity amongst his builders, and indeed many of the cycles built from Brad's plans show various minor (and sometimes major) deviations from the plans. So I didn't feel that someone using forks for the front wheels would disqualify a build from being an Atomic Zombie trike, or outside the realm of possibility for an Atomic Zombie builder to do.

And the weight savings I was referring to was if one built the front wheels in the conventional way, i.e. no forks. In other words, you would have a weight increase if you used forks.
 
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I'm aware that none of Brad's trikes are built that way, but Brad also welcomes and encourages creativity amongst his builders, and indeed many of the cycles built from Brad's plans show various minor (and sometimes major) deviations from the plans. So I didn't feel that someone using forks for the front wheels would disqualify a build from being an Atomic Zombie trike, or outside the realm of possibility for an Atomic Zombie builder to do.
Yes I just meant to the best of my knowledge there is no experience here of people using front forks , we try to advise anyone who comes along asking questions , whilst I have bought lots of Brads plans and both his books my trikes are only built in ' the style of ' I have yet to build one of his designs . However there is always tomorrow ;)

The trickiest part of a tadpole build is kingpin angle , being angled both back and inwards I suspect that will be made many times harder if you have to do it for the head tube and then also for the front fork being used ? Also some forks also have rake which will complicate getting the angles right.

And the weight savings I was referring to was if one built the front wheels in the conventional way, i.e. no forks. In other words, you would have a weight increase if you used forks.
Sorry missed the word ' conventional ' , seems to completely change the meaning of the sentence :rolleyes:

At this point you really need a tadpole builder to come along and comment , I am purely a delta man and have a slim understanding of all this castor , centre point and Ackerman voodoo ....
 
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Oct 19, 2012
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Wakefield, UK
I think the trikes that use the full front forks often look somewhat cobbled together. The design just doesn't flow.
 
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