fitting a motorcycle fork onto a bike?

General Discussion about electric bicycles.
Yungyakz   10 mW

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Re: fitting a motorcycle fork onto a bike?

Post by Yungyakz » Jun 28 2019 7:01am

Bluefang wrote:
Feb 12 2014 1:59am
I have used Pit bike forks on a pair of my builds for the extra braking power and cause i am cheap. You should just go to the junk yard with some measuring tools and see what will work, i managed to get both forks for around $100 each including some shitty 21" wheels that i reused the hubs and spokes from the 21" moto rim to lace a wide aero 26" bike rim too(Almost perfect fit, spokes were a fraction short so i drilled out the spoke holder on the hub by 5mm giving me enough to get the right amount of threads engaged). Also came with the full brake setup, had to space out the brakes to fit the larger 21" wheel avaliable disc sizes. The other i left as a 17" moto wheel.

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Hi, im interested in doing this, did the forks fit into the bike headtube or where there any adapters you had to make etc.

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stan.distortion   1 W

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Re: fitting a motorcycle fork onto a bike?

Post by stan.distortion » Jun 28 2019 8:54am

Some of the 50cc forks might be worth looking at but I doubt it, more or less all put cost before quality, heavy for what they are and poor damping. Girder forks are worth considering, kind of surprised they're not more common tbh, light, relatively simple, MTB rear shocks should work well with them... Worth having a look at BMW motorcycle front suspension, they did a re-think on girder forks for their high spec models that works very well and their telelever suspension has to be tried to be believed, miles ahead of conventional forks imo.

Olds C0ol   10 µW

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Re: fitting a motorcycle fork onto a bike?

Post by Olds C0ol » Jul 02 2019 3:58pm

Why bother? You can buy new "triple tree bicycle forks", for $80- 150, made for your bike, that dont have the Excess weight, of a motorcycle set-up. Also they're disc ready. Go shoppig; Olds C0ol

markz   100 GW

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Re: fitting a motorcycle fork onto a bike?

Post by markz » Jul 06 2019 2:38pm

I had to go look up what the girder forks were, close enough to a springer fork. Those do look like something anyone can build. I was thinking of building one, and using coil springs that had a wide variety of compression rates so you can play around with rates.

Sunlite and the other ones you can buy for $100 on ebay are useless and a waste of money.

https://www.custom-choppers-guide.com/g ... allery]/3/
stan.distortion wrote:
Jun 28 2019 8:54am
Girder forks are worth considering.

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MadRhino   100 GW

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Re: fitting a motorcycle fork onto a bike?

Post by MadRhino » Jul 06 2019 3:57pm

Nothing comes close to a modern DH racing fork. Their action, tuning options and weight, is making pro motorcycle custom builders replace motorcycle forks with bicycle forks in many fields of competition. In Trial motorcycle world cup notably, all bikes are mounted with bicycle forks for quite some time.

The pit bike forks that some are mounting on ebikes, are absolute crap. Good motorcycle forks are heavier than a whole touring bicycle plus the equipment that an average cyclist is wearing.

Apart of some, very few and very expansive, girder forks made with carbon fiber and designed with modern tuning options, the usual springers and girders are heavy with poor action control. Fancy looks to build a show chopper, is all that they have.

Motorcycle components may be good to build e-motorcycles, on ebike they are poor choices. After your power beats 40hp, you can start looking at motorcycle components.
Make it fool-proof, and I will make a better fool.
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