Bike Builders Unite

[Tiahaar]

that place with the same name as a South American river currently has a deal going on the mongoose dolomite if anyone is searching for the perfect 7-speed (IMHO) playa bike...

[FIGJAM]

No more pesky chain!!!

13245391_1043342159089565_8447456326813955915_n.jpg

[EGAZ]

Now that's art to me......

[FIGJAM]

Maybe everybody else knew this, but I didn't.

The reason girls and boys bikes are designed differently goes back to Victorian times.

The ladies bikes had to accommodate those massive dresses, and the cross bar would cause the front of the dress to blow up in the face while riding.

The cross bar today is there to make the frame sturdier.

[EGAZ]

I always thought it was because it was/is not 'lady like' to throw ones leg over the rear tire like the guys do......

The more you know.....

[Elliot]

Problem solved.

[EGAZ]

That it is.....

[Elliot]

Whoa!
That image violated Photobucket's TOS.
Reckon I will attach it directly instead.

Naked_Ride-Velocipede-Vintage.jpg

Problem solved. Twice.

[Elliot]

No more pesky chain!!!

13245391_1043342159089565_8447456326813955915_n.jpg

That is absolutely lovely!
My only concern is the structural integrity and alignment of the two large gears. It would be nice if they were wider.

[maladroit]

I guess I'm not cutting up a pair of Mongoose Beasts and making a quad bike this year...someone broke into my place and stole one of them!

[Ratty]

That sucks! Having anything stolen sucks. Sorry to hear it.

(I'm saving my wisecracks. Too soon.) Maybe something really GREAT will come to you now by way of karma equalizing. I hope.

[maladroit]

That sucks! Having anything stolen sucks. Sorry to hear it.

(I'm saving my wisecracks. Too soon.) Maybe something really GREAT will come to you now by way of karma equalizing. I hope.

Oh I've been bad, this IS my karma equalizing

[Tiahaar]

Booooo on bike stealers! Hope you still get a cool beast project going, maladroit. Since you still have one, a trike or sidecar? Oh and if anyone is thinking of getting the 7-speed Dolo also spring for the mega-range 7-speed freewheel and do a swap-in so you have an awesome low gear you will love.

[unjonharley]

An hour on the recumbent trainer,, Set on #5 drag of 18.. Broke a sweat the last ten minutes.. Add one drag # each day..

I am getting ready for the dust... Will be trying for a bike like my avatar with side (powered) car.. Da vinici-ed and Steam puked..

[Elliot]

I'm planning to convert my fat-tired trike into a bike with sidecar. We might start a trend!

[Ratty]

Unjohn! You'll be there this year? YEA! I'll find you.

[unjonharley]

Unjohn! You'll be there this year? YEA! I'll find you.

I'll be there making a pest of myself @ Elliot's bike repair.. Have a couple of vest for you to gift..

[Captain Goddammit]

Union, you're coming? Yay, I don't have to be the ugliest person on the playa this year!!

[Ratty]

Be nice to Unjohn 'youngin'. You may need some wise advise.

[Elliot]

Darn right Unjon will be in our camp!

[thnkfl]

The 3-speed transmission on my old trike is shot. I'd like to either replace it or, if easier, substitute an axle that has the two necessary gears fixed on it and convert the trike into a single speed. Right now, the pedal crank has 36 teeth connected to 19 teeth on the trans. From there, a 28 tooth gear turns an identical gear on the differential. I don't need the existing coaster brake. The bracket that holds the trans has 120 mm spacing. I found a replacement that seems it would fit http://www.sheldonbrown.com/harris/shimano-nexus.html but I don't know if a second gear would fit on it. I hesitate just running one longer chain from pedal to differential because of the offset of the gears.

Also, since this is only for playa use (5 mph), should I consider a different gear ratio than 36 to 19?

Any suggestions? Thanks.

[Captain Goddammit]

The reason you don't want to run a chain all the way back to the axle and skip the gear hub is because you'd lose your ability to coast.
There's no 5 mph speed limit for bikes (or trikes like yours).
You can use any old rear hub from any bike in place of your existing three speed hub if you can handle removing the spokes and attaching a sprocket on one of the flanges where the spokes were.
Otherwise just buy a trike hub. I'd go with at least a three speed. Mine came with a three and I ended up swapping it out for a five speed hub.

You'll save yourself the fabrication work if you buy a trike hub instead of that bicycle rear hub in your link. A trike hub will have the sprocket to drive the short chain to your rear axle already on it.

[FIGJAM]

That looks like one I had to replace and it was $150 for the part.

[Elliot]

In the photos, I cannot see how the final sprocket is attached. It seems like the shaft is behind the frame crossmember, rather than inside it.
If that axle is a common diameter with standard keyway, and you can get the sprocket loose, you can replace it with a regular freewheel by using an adapter. These adapters cost about $15 online, and a single-speed freewheel about the same. Wait.... You can use a multi speed freewheel (maybe $20 or $25), and set it on the axle to use your choice of sprocket.
I can give you a link to the adapter, if you like.
That said, I strongly recommend some gears. You could add a derailleur on that multi-speed freewheel! Fabricating a derailleur bracket is not difficult.

EDIT to add:
You can get a 14 to 34 tooth freewheel of 15.99, delivered to your door.
http://www.ebay.com/itm/SHIMANO-MEGARAN ... xydUJTOIf4

[Elliot]

Here is a freewheel adapter for 3/4" axle.
http://www.staton-inc.com/store/index.p ... uct&id=985
They have an impressive selection of such.

[thnkfl]

Thanks for the responses, gents. I'm not sure I understand how Elliot's suggestion of a 3/4" freewheel would work in place of a hub, unless that would substitute for a hub? Here are a few more photos, if they make any difference.

Anyway, I have an appointment with my local friendly bike repairman at the end of the week, and will show him what you suggested.

[Elliot]

Wow! You have a differential! Very cool. Most trikes drive only one wheel.
This is an open diff, so you can still get stuck if one wheel loses traction. But you don't have the problem of difficulty turning sharply to the side of the driving wheel.
Let me think about this for a while.

[thnkfl]

Well, my friendly local bicycle repairman convinced me that all that was needed was an adjustment to the shift lever, altho 2nd gear remains somewhat problematic. He got it working reasonably well and thought it would last another couple of trips to the playa. All things considered, I figure I'll trust his word on it. See you in the dust in deep playa!

[Elliot]

Ah.... Well, I do tend to make the mistake of guessing at someone's skill level.
Since you pronounced the transmission "shot", and made a reference to the holy ghost of Sheldon Brown, I figured you knew a thing or two about cables and adjustments.

Well... now you do! (*crowd cheers*) Keep learning, my friend.

By the way, the late great Sheldon Brown was the master of all bicycle gurus, and he put everything on his website -- and with humor! After he passed on, others are keeping the site updated. http://www.sheldonbrown.com/

[Pootzen]

I had no idea Sheldon passed away so long ago... we had a nice correspondence back in 2007, and I thanked him for the gift of "bike knowledge".