My Customised Chopper

[Thorlek]

Hey all...

Here are some pics of my chopper as it is now...

http://i48.tinypic.com/30rv1bq.jpg
http://i47.tinypic.com/28hjx9g.jpg

Anyone added gears to these choppers? it seems the rear hub/axle is too long to swap out from another bike or put a cluster on.
and the internal hub gears all seem to short.

[hartleymartin]

If the problem is getting up inclines look at getting a bigger sprocket/freewheel on the rear. That'll bring the gearing down and make it easier to ride. However, I don't see this as being a bicycle that you'd ride very far on.

[jaffaman]

Way cool bike! Does that seat post actually provide shock absorption, or is the spring just for show?

If the internal hub gears are too short (i.e the hub is shorter than the one on it), you should be able to just add spacers to make it fit? What is the distance across the back from the dropouts on each side?

[Thorlek]

theoretically the post does provide shock absorption, but because of the angle its on its fairly minimal.
If it was straight up and down it would work much better.

The dropouts are about 18cm apart (from memory) and the axle in there at the moment is 20cm.
once the axle is through the dropouts and the the sissy bar is attached, the nuts only just have enough thread to grab onto.

So far the longest internal hub gear I've found haves a 17.5cm axle... which is just not going to cut it unfortunately.

I think for a start I'm going to get a bigger sprocket at the back and see how that helps.... i still want gears long term tho.

[Wild Turkey]

You can run 3 gears on this bike!

I had planned to do this to one of mine, though never found the time.

You will need some MTB parts.

First get some tripple chainring cranks from a MTB. Your bottom bracket is a square taper so old MTB stuff should bolt straight in. This gives you 3 gears up front. You can even mount the shifter under the seat for extra custom. You will need to remove the BB and fit a front derailuer that is designed to clamp up using the BB. As opposed to the normal ones that clamp to a seat tube. And yes you will need to ditch the chain guard and run a MTB chain or two.

Now down the back on the rear drop out. You will need to mount a rear deraileur. Two ways to do this, either get an old one that is held on by the axle and nut. Or drill and tap an M10 X 1 mm hole in the right spot on the drop out to hang a modern derailuer from.

This rear deraileur is only there to take up the slack in the chain when you change gears up the front. Screw the adjusters in so it is locked in the one spot. A long cage will be better but don't scrape the ground with it.

Let me know if this makes sence?

[Thorlek]

First get some tripple chainring cranks from a MTB. Your bottom bracket is a square taper so old MTB stuff should bolt straight in. This gives you 3 gears up front. You can even mount the shifter under the seat for extra custom. You will need to remove the BB and fit a front derailuer that is designed to clamp up using the BB. As opposed to the normal ones that clamp to a seat tube. And yes you will need to ditch the chain guard and run a MTB chain or two.

I was worried the frame / bottom bracket would be too long (wide?)? its almost twice as long as the BB on any mountain bikes i have on hand to use for parts

Other that that it all makes sense... I just don't know if I'd be able to do it my self.... do i need any special tools?

[Wild Turkey]

A good LBS should be able to sort you a rear deraileur. Remember it is only there to take up the chain slack from chainging front rings. And you may need a hole drilled in your RH rear drop out. This wont need to have a shifter hooked to it. You will just need to wind up the adjuster, so the jockey wheels are aligned with your rear cog.

The BB will take a BB mounted front deraileur. I have a Downhill MTB "Chain Device" fitted to one of my bikes, the same model as yours. This chain device bolts up just the same.

MTB square taper cranks will fit. I have MTB cranks on mine. You will need "Tripple chain rings"

You will need a 3 speed MTB front shifter. They generally go on the left side of the handle bar.

Can anybody catch my drift? I think a good tweeker should be able to follow this through.

True chopper riders are also chopper builders! Don't be affraid.