OCC Chopper Bike Build

I've started work on my new build, an OCC Chopper bike I found in a dirty garage. I've already spent several hours on my projectt and I don't even have a kit!

These things are not perfect for motorizing, as the engine has to be kicked left with the end result being the right rear engine mount stud is close to center of the frame. I could have dropped $40 for a pre-fabbed motormount but I simply don't have an extra penny to spend on this. I've created by own by measuring carefully and drilling holes in thick metal. It's a system of transition plate and muffler mounts that I've used before.

The saddle was trashed! I found some material and worked up a new cover with some homemade rivets. It wil work for a while!

The V-brakes, front and back, are good but the headset cap is trashed. I have to rig up some kind of fix to get a tight setting on the headset.

The handlebars are just weird an I don't want to use them. I'll find a simple straight bar as that will maximize function. In traffic you want narrow bars to sneak through tight spaces.

I patched the rear tube but I cannot inflate the sketchy tire because my floor pump failed. My frame pump that I carry for my push bike commutes to work has mysteriously disappeared from my backpack. It doesn't reay matter though because I bought a very cheap motorcycle tire on ebay as I am told they will fit on the fat rear rim. But, boy, this thing cannot be mounted like a bicycle tire. I am going to have to spend $20 for a motorcyce inner tube and maybe buy a few tire tools. There are some hacks on youtube - not sure how I will settle this. If I use the moto tire I will use a 40 tooth sprocket. If I have to default to the 20" bicycle tire, then it will be 36 tooth. At any rate, there's a lot of work ahead for me before this thing yanks me down the road!

Here are some pics:
 

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You have a good eye! It's too much trouble to correct the rotation direction mistake! Hard work mounting a motorcycle tire with hand tools!

I cut a 25T Ultegra cog from a cassette block - it will fit perfectly, allowing me to move the pedal chain 3/8" to the right and off the big tire.

I have all the parts for my jackshaft. Just need to sit down and take some very precise measurements to know exactly where to lock in the sprockets, bracket and bearings. I'll put pictures up.

I think it will look better with a more regular saddle.

Thank you for the compliment, sir.
 
Offset (what I'd call rake) is there to offset the excessive trail that would otherwise be caused by the extreme rake (what I'd call head angle).
(Sorry I'm such a pedantic tw!t, I think it's a mental health issue.)

A fork with less "offset" would not offset the trail. The bike would be difficult to steer at low speeds. However if you just ride everywhere really fast it could be a good thing. Schwinn's designers didn't intend you to ride with engine power anyway.
https://en.m.wikipedia.org/wiki/Bicycle_and_motorcycle_geometry

I think the 26" wheel looks right because it makes the frame level (since you raised the rear by putting a huge rear tyre on it).

I'm not sure what dual crown mountain bike forks would fit the headset/head tube but I'm sure I have read about a moped or light motorcycle fork with a 1" steerer (and a specific wheel) being used in other motored bicycles in the earlier threads on this forum.
I suppose it could get expensive but at least it allows you to mount a front brake and another motorcycle tyre on there could be pretty cool. :)
 
Thank you for the input on this fork rake/ trail issue!!!

I am an old bicycle racer so all I know is twitchy quick handling that comes from steep headset angle and little rake. I do understand these terms.

When referring to "offset", I wasn't referring to rake or to headset angle. If you look at the triple tree, you'll set that it is offset - not parallel - away from the head tube angle. I'm thinking that, with the extreme rake, this decreases trail which may explain why the bike was barely rideable with a 20" rear tire and 24" front tire.

I'd like to have a whole new triple tree while adding suspension, decreasing rake and keeping the fork tubes parallel to the headtube angle.

What do you think? TIA
 
Thank you for the input on this fork rake/ trail issue!!!

I am an old bicycle racer so all I know is twitchy quick handling that comes from steep headset angle and little rake. I do understand these terms.

When referring to "offset", I wasn't referring to rake or to headset angle. If you look at the triple tree, you'll set that it is offset - not parallel - away from the head tube angle. I'm thinking that, with the extreme rake, this decreases trail which may explain why the bike was barely rideable with a 20" rear tire and 24" front tire.

I'd like to have a whole new triple tree while adding suspension, decreasing rake and keeping the fork tubes parallel to the headtube angle.

What do you think? TIA

I'm pretty sure that the only one with the 1" steerer is the old moped fork (and matching wheel) that is mentioned in some old threads here.
http://motoredbikes.com/attachments/bike5-jpg.29139/

I only know of one "real suspension" mountain bike fork (single crown) with a 1" steerer.. the Marzocchi MX Pro if I remember the name correctly, made as late as 2006.. but you said you don't want a single crown fork anyway.
 
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I wouldn't really use those triple tree from schwinn they are thin,weak and just scary to me!But there are many ebike front ends with suspension that will work!also many triple tree sets that can be adapted to accept enduro suspension tubes. or the jesse james set that will accept 2"plus dia tubes.
 
I'm pretty sure that the only one with the 1" steerer is the old moped fork (and matching wheel) that is mentioned in some old threads here.
http://motoredbikes.com/attachments/bike5-jpg.29139/

I only know of one "real suspension" mountain bike fork (single crown) with a 1" steerer.. the Marzocchi MX Pro if I remember the name correctly, made as late as 2006.. but you said you don't want a single crown fork anyway.
Actually, my OCC Chopper bike is set up with a 1 1/8" threaded steerer which means I could use a threadless fork setup. I have plenty of options, but not a lotta money.
 
Actually, my OCC Chopper bike is set up with a 1 1/8" threaded steerer which means I could use a threadless fork setup. I have plenty of options, but not a lotta money.

Then I would check eBay etc until you find some old Marzocchi Junior T's. The open oil bath system is very easy to work on, you will need to replace the bushings often with that head angle. Probably better check the availability of bushes tbh.
You can overfill with 10wt oil to make it stiffer, shorten the travel a bit and then you can lower the crown's slightly I think, to shorten the fork. Junior T's had about 5" travel originally I think..

_20161013_152500.JPG

I have put some old Marzocchi forks on an inverted bmx cruiser frame just to see how it would look. Idk which model of Marzocchi Bomber fork it is. It could be a custom mismatch of the top and bottom.. anyway I can feel the front wheel just wants to flop over because there is not enough rake for the crazy head angle. It might be okay with some kind of spring thing to help centre the steering, idk.. it's a future (electric uplift) gravity bike project and I am far from being ready to start. I don't mind that running the fork at this angle will undoubtedly ruin the bushes because I don't plan on riding it for many miles
 
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Still making progress. I've bolted a 25T sprocket onto the pedal side freewheel moving the chain a full inch to the right to avoid the big tire. Picture provided. Had to add a 3/8" spacer.

Also, I've fabbed up my left side jackshaft to clear on the left side. Here's a pic of the sprockets on the shaft.

Also, prepped up my chain tugs so I can size and mount the pedal chain and make this a rolling chassis.

Still need to bolt on my jackshaft bracket, set the shaft and lock everything into place so it's ready to take the 415 motor chain.

I am pretty sure the rear V-Brakes will work so I can put my Sprotor project into the experimental file.

Get a fat seat post, get a spring saddle and get a kit - this thing will be rolling!
 
You'll want to measure those 2 sprockets on the shaft, they look really wide honestly, and that might mean that you'll have a hard time getting a chain to fit them. On another bike we had a sprocket that was too large to fit the standard chain that comes with kits, we ended up putting it on the right side of a jackshaft shaft and turning the motor on to make the sprocket spin as I took an angle grinder to turn the width down to an acceptable size. Took nearly an hour of careful work so don't expect results in 10 minutes of you try something like that.

I would think that twice as long with a belt sander and the right belt could do it too if you needed to do it without it spinning but you'd have to be careful to make the teeth all the same size or it might wear the chain out oddly or other similar problems.
 
Thank you for the comments!

First, about the pedal sprocket: it's a racing cog (Ultegra) that was part of a cassette block of the three biggest rings. They were held together by several small rivets and they took a long time to cut off! The new 25T cog is made of very hard steel. The ten bolts fit perfectly and I use nuts as spacers. Nothing can move as there is nowhere to go. The ring would have to shatter!
I will take you advice and use blue thread lock on the outer nuts.

These sprockets aren't very large. The shaft is 7" (that's what she said) and I was careful to order them specifically for 415 chain. I've test fitted and they are perfect.

I had the a similar experience on my previous motorbike, being forced to carefully grind down each tooth on the one piece crank that wouldn't accept my BMX chain. No fun!

Thanks for the input!
 
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