Shanghai Scrambler

[wrenching4fun]

I got out of the game early last year and was left with a couple of bins of parts. When cabin fever set in this winter, I was going to build an ebike, but decided instead to throw the spare parts on my Northrock mountain bike. The attached photos show the end result. I tend to go into way too much detail when I describe a new build, so I'll just say I took it out for a spin today and reached 40 mph in 4th gear before I ran out of street in my neighborhood. Feel free to ask questions and thanks for looking.

 

[Greg58]

Looks good, have fun.

 

[wrenching4fun]

Thanks, Greg. It is fun. Trying to decide if I should install mud guards since we're entering monsoon season. Looked on Amazon and Ebay and can't find any that look right.

 

[Chad_Broski]

It almost look looks a pocket bike

what are the stats?

 

[wrenching4fun]

Hi Chad. Stats are stock-jetted Chinagirl with an early expansion chamber and Statton shift kit connected to 7-speed derailleur. The motor mounts were customized for this bike. A 12 volt lighting coil and rectifier run a 1000 lumen LED headlight, dual LED tail light, and moped horn that's operated through the shutoff switch on the throttle. No brake light is set up yet. All electrics like CDI, rectifier, fuse, and keyed ignition are housed in a hinged metal box for weatherproofing. The brakes are mechanical Avid single pad calipers on 160mm discs operated by a dual break lever. The front will be upgraded to a 203mm. No chain tensioners were used because I've found them to be problematic. An extra sprocket was installed between the primary drive sprocket and frame to serve as a jump stop. Tires are WTB Rough Terrain 26 x 2.25 knobbies on standard MB rims. The speedo is a high quality vintage Stewart Warner and the mirrors are motorcycle mirrors from Amazon. The frame is an all aluminum rigid tail with Suntour front shocks and either Walk or Bucklos handlebars (can't remember). Both wheels run on hardened quick-disconnect axles. I made the springer seat from spare parts and scrap leather. The hand bar on the rear makes it easy to work the rear wheel stand for kickstarting (the freewheel on the cassette prevents bump starting). It took a while to get used to the Shimano shifter, but once I realized you don't need to clutch with a derailleur it shifts like a semi-automatic motorcycle, smooth and even as long as you decelerate when shifting. I don't know the top speed-I'm guessing around 50. Hope this helps. Let me know if you want to know anything else.

 

[Chad_Broski]

Amazing, is the bike frame aluminum or steel? Also, how much do you thing you have invested in everything?

 

[wrenching4fun]

It's an aluminum framed Northrock I picked up from Costco some years back. I didn't keep records and I bought most of the parts a long time ago, back when a dollar was almost a dollar. To give you an idea, the engine kit was about $100, the bike was $250, and the pipe was about $50. Add another $100 for the lights, horn, shift kit, and you're looking conservatively at 500 bucks. It could be done much cheaper by picking up a solid bike at a thrift shop or as a give-away. People around here sell them at garage sales for as low as $5.00. I only used my MB because it was there and it was set up with discs and an aluminum frame like I wanted. You can't really base this hobby on economics. It's like golf, you pay a premium for the experience. If I went to sell this bike around here, I'd be lucky to get $200 back from my $500 investment. I just chalk up the difference to the sheer fun of riding something no one else has. In my humble opinion, if you want cheap reliable transportation on two wheels, get an ebike. If you want the satisfaction of accomplishing something with your own two hands, put one of these together.

 

[Chad_Broski]

I love it, looks amazing!

Is it "street legal"? I know that here in my state it would have to be registered as a moped since it goes more than 20mph, but I didn't notice a tag.

 

[wrenching4fun]

Thanks, Chad. Glad you like it. I intend to use this bike off-road most of the time, but I have never been hassled for riding any of my MBs on the road. Local cops have stopped when I was parked a couple of times and they just looked at the pedals and were okay. Obviously, I don't speed past cops or do anything else to draw unnecessary attention. I will not be registering this bike, but you need to do what's right for you. BTW, what state are you in?

 

[Chad_Broski]

NC

 

[wrenching4fun]

Me, too. Which county?

 

[Chad_Broski]

Iredell County*

 

[wrenching4fun]

I haven't spent much time in Mooresville or Statesville so I don't know how strict the police are there. Both seem to be busy areas with a lot of traffic so I suspect there's stricter enforcement than here on the coast.

 

[Chad_Broski]

I suspect there's stricter enforcement than here on the coast.

sorta, I wouldn't really know bcuz I/we literally live on the border to the next county over, Alexander. I/we usually spend most of our time there. The police there are...okay. They are more or less just like any cop nowadays, They think they are just "all that" and that their crap don't stink. Though what do you expect when you give a person so much authoritative power? While on duty, a Peace Officer is not legally obligated to provide their name, badge number, or reason for detainment of any suspect. Peace officers are also permitted to force you out of your own vehicle and it is advised that you "remain silent" throughout the procedure. All of these tend to facilitate a nightmare scenario; Cop attempting to abduct someone pulls you over, doesn't have to ID themselves or tell you why you're being pulled over, you MUST get out of the car, you're advised to keep your mouth shut and go with them, 'by law.' You are ‘knocked out' by a punch, next thing you know when you come to, you are in a secluded cottage in the middle of nowhere being raped every 10 minutes.

 

[wrenching4fun]

Are you building a bike or just thinking about it? BTW, we know some people in Morganton. What's your opinion of Burke County?

 

[Chad_Broski]

Are you building a bike or just thinking about it?

I have already built one, I just have yet to post pictures.

we know some people in Morganton. What's your opinion of Burke County?

That's a though one, we almost never go there unless we are going out-of-state for leisure. Though there is one time I remember that we went there (Morganton) to take my brother to counseling, but they said there was nothing they could do for him, so essentially we just took a mini vacation to the foothills.

Never had a chance to meet any of the locals cuz we only ate at McDonalds

.

 

[wrenching4fun]

Put some time in the garage this morning. Moved the speedo to the side for better cable alignment, and raised the headlight to the handlebar for better light projection and to free it from suspension shock. These bikes are a constant work in progress.

 

[wrenching4fun]

What is the best shifter for a shift kit? I currently am using a Shimano right hand 7-speed shifter. I like the push button up shift feature, but don't like shifting and throttling with my right hand. I have a left hand Shimano 7-speed twist grip shifter squirreled away someplace and am thinking about switching them out. Besides moving the shifting to my non-throttle hand, I'm thinking it will be easier to keep track of what gear I'm in with the twist grip. Any thoughts?

 

[wrenching4fun]

Back in the Skunk Works after buying some fenders on a junk bike at a garage sale for a whopping $1.00. Sanded off the rust and primed, then painted with Red Anodized Dupli Color. After screwing up the front fender I had to learn how to paint all over again. I used the goose neck from the donor bike to make a front fender mount that inserts in the bottom of the steering tube. The front fender was cut in half and mounted to an aluminum strap that is held in place by the inverted goose neck. The hardest part of mounting the rear fender was dealing with the derailleur when the rear wheel was removed. Will paint the tank and electric box to match after a short break for riding.

 

[wrenching4fun]

I got tired of tuning the carbs on my two bikes, so I came up with a fun distraction. I mounted a moped tire pump behind the gas tank using a metal pin on one of the gas tank mounting screws and a plastic tube strap with a pin built in. The spring loading of the pump holds it between the two pinch points. These nifty little pumps have a hose that slides in the housing for storage. When the hose is in place the schrader screw-on connector fits over a pin that holds the pump in place. I always carry a patch kit and two tire spoons with me just in case and the pump will allow me to re-inflate after repairing a puncture. Have been looking for moped-type tires for bicycles, but can't find any that are nearly as durable as the Heidenau K-56 tires on my little SACHS that are constructed like motorcycle tires and haven't suffered a puncture in 5 years of riding. Anyway, now that I have my pump installed, I can deal with a flat.