drop out widths?
 

I am searching for a folder to mount my 20" hub motor wheel. I found the Dahon Vitesse has a 3" front dropout rather than the standard (for non-folders) of 4". I'm wondering if any of the 20" folders have 4" front dropouts? Are there standards for folders that are different than non-folders? Robert

I have a follow-on question. My LBS said they spread the 3" fork to accommodate a 4" axle on Dahons. This seems like a lot. Has anyone spread a Dahon fork to mount a standard 4" axle?

Swift, and I think Bike Fridays, have standard fork widths. I'm sure there are others.

Thanks. The Swift looks attractive; I will do a search to see what folks have to say about it.

I was wondering if I could swap out the forks on a Dahon (used Dahons show up locally from time to time).

The current Raleigh Folding I8 uses a standard-width front fork. However, the fork is aluminum. That might be an issue with your motor wheel.

-HANK RYAN-
Norman, Oklahoma USA

Be sure to check out the monster Swift Folders thread.

I have no idea about being able to swap out the forks on a Dahon, but my gut is telling me no. The Swift uses a 1" threaded fork. I have no idea what Dahons use, but I'd bet you'd be looking at least at swapping the headset. There would also be the little matter of getting the Dahon folding stem to work...

Where are you located? Used Swifts do show up from time to time. If you are in the UK, I know someone who is looking to shift a framset.

Most folders have 100mm dropouts; except Dahon, Brompton and BF tikit.

It will be difficult to swap a Dahon fork; these are custom for Dahon.

If you have a steel fork Dahon, that could be spread by an expert; 12mm on a side is IMO too much for cold-setting.

Human Powered Machines in Eugene is a small shop , their Swift version's fork ,
by virtue of being made there can even be made up with wire guides brazed on
before the powdercoat, is done, in house.

I'm not aware of Da Hon's specifics, but if you give one to a decent, flexible,
frame builder, it can probably be replicated, say, with a wider fork crown ,
and the blades splayed out. alignment, via, jig modifications ..

yep. 74mm front hub that allows a more compact fold.

downtube folding bikes have the standard 100mm front hub and are licensed by dahon.

I think that DT has one model which is licensed by Dahon, which has 74 mm fork, the other ones are indeed his very own design and might come with 100 mm ... but Jan is easy to find shoot him the question direct to make sure ...

thor

p.s. its not so much the fork alone..... there are plenty out there.... but also how to secure the stem .... if you do not have the correct fork diameter and no thread ( thread pitch etc etc ) inside the fork, how will you attach the handlepost ?
I would think that very very few people can make an inside thread which will be secure enough .....

Many thanks for all the info. I am writing off the Dahons for all above-mentioned reasons. I can see there are other options for folders that would be better suited to my needs. In another month my LBS will have a couple more Giants in his showroom to look at, and I will keep an eye on Craigslist. My other (cheaper) option is to buy a kids 20" bike and put a long seat post and stem on it; I think the stem is easy but the seatpost can be tricky due to the variety of diameters out there. And I would need something with a reasonable wheelbase. Robert

there are also bikes like the silgey mini velo which don't fold, but are quite sturdy and use standard parts.
The folding version (actually this would be the original) would be a moulton, although I'm not sure how sturdy the fork is on a moulton or the hub width.

Watch out re the Giants - there are models with a single-bladed fork which would also be useless.

I thought that was the cannondale hooligan?
It uses the lefty... but the lefty has been recalled before when it was on MTBs.

Smaller front fork widths are common on folders/smaller wheeled bikes.

I have a hub motor running in my Brompton. Its a Tongxin. Even these forks required spreading a few mm to fit the 83mm wide hub motor. You may also fine you have to open up the fork drop outs a little or a least scrape off the paint coating. Its probably better to use steel forks especially if you are using a motor more powerfull than 250watts. Then you should also fit a torque arm to stop it spinning out of the dropouts when applying power :eek:

The Tongxin is perfect very light, narrow, virtually silent and just enough lite assistance (180watt) to make my longer commute possible with my medical condition. It has enabled me to commute daily on my bike for the last two years/3000 miles and transformed my working day. This narrower lighter motor does not compromise the Brompton's fold and enables me to retain its excellent portability. I still carry it in and out of my office every day, nip in and out of shops to get things and pop into coffee shops with it :D


http://farm6.staticflickr.com/5308/5...e5ea3b95_o.jpg


I have also tried one in my Moulton TSR2 which has 20" wheels.


http://farm7.staticflickr.com/6109/6...7364c0d3_o.jpg


Although this has 100m front fork spacing, a narrower hub motor is required to clear the suspension components.


http://farm7.staticflickr.com/6231/6...0e60ed27_o.jpg

Narrower width hub motors are hard to find. I think Tongxin and Cute are about the only two available. Which one do you have ?

Regards

Jerry

Here is how I spread my Brompton forks that extra few mm. About 10mm if I recall. If they are steel you may be able to cold spread them more than that as I have seen people do it successfully up to 15mm more than I did. All done at your own risk of course though. As stated by another poster though if the bike is like the Brompton you will compromise the fold if you spread them too much.

When you adjust the nuts to spread the forks you have to do it bit by bit and make sure you keep pushing the threaded shaft back into the fork dropouts, as it tends to want to ride up and spring out. Be careful when you do it :twitchy:


http://farm3.static.flickr.com/2681/...160c0a8f_o.jpg

Regards

Jerry

How can this possibly be defined as "most folders"?

jur jur jur ....
we love you !!!!!!!!!

but you have to add a couple more folders to the list of 74 mm axles.... like DT, some Raleighs, Cosmo, all Dahon licensed bikes, and and and ....

maybe you meant : most folders currently in my stable ...

Peace
thor

who is waiting for a Dahon Formula with disc and 100 mm fork

actually, the raleigh R20 use 76mm raleigh special forks and hubs.
along with other strange raleigh bits and pieces...

AEO,
Thanks for the tip about the Sillgey Minivelo. I would have never found it and it looks exactly like what I could use. And the $250 price makes it quite economical. As long as the frame is good, I can live with whatever scrimping they did with components to reach that price point. Do you have any experience with sillgey frames?
Robert

I don't have any experience with the sillgey mini velo, but I haven't heard anything bad about them.

there's also this geared version from BD: http://www.bikesdirect.com/products/mercier/nano.htm
I think the difference is in the rear dropout and rack/fender mounts. the SS/FG version is more suitable for IGH.