It's Too Many Good Ideas Syndrome, you've worn your brain out Maniac.
Hope you will be feeling better tomorrow
Hope you will be feeling better tomorrow
Rack mounting a chinagirl
- Thread starter maniac57
- Start date
Finally found the time to test ride the rack mount this evening.
The brand new engine (Thanks to Jim Wilson at Pedalchoppers!) fired right up and off we went for a nice half hour test ride around the neighborhood. My initial impression is that this is one of the nicest chine girl powered bicycles I have ever ridden. Even though the bike itself is rather cheap and flimsy, with the motor pushing you along, it rides like a Cadillac! All the motor and intake noise you hear in a frame mount bike is behind you and inaudible. All you hear is the exhaust tone. No ringing, gear whine or tinny side cover noise at all. I'm very pleased with the first ride and am looking forward to playing with my newest toy! This is turning out better than I had hoped.
It was problem free with nothing flapping or bending. No grinding noises or ugliness to sully my very first miles. I did get some chain stretch from the cheap stock chain so I will have to redo the mount or install some kind of tensioner to get the chain right.
I'm considering a roller guide like this.
Also have a very small issue with the seat frame tapping the pipe a bit at full travel, but this will be very easy to fix by simply jacking the frame up a touch by moving the shock mounting point. Instant clearance and a slightly stiffer spring rate for ten minutes work. (This easy fix is why I was downplaying the problem to those of you who warned of interference)
Trying out the roller setup tomorrow. If it doesn't work as well as I want, I'll start working on a fully adjustable pivoting mount like the final version I've been seeing in my minds eye. This ugly hack job of scrap and bits is just a first draft.
Please believe I do nicer work than this rough prototype. This was built by me holding stuff in place and blind tacking it together, stepping back and eyeballing it, bending to suit, then welding on bits of handy scrap until it wouldn't move anymore. I have a very organic process when trying to create order out of the chaos that is my usual work area. My prototypes tend to be very ugly and disorderly looking, yet very strong for the purpose needed. I'm real good and making whatever is at hand work. Making it pretty and sleek is something that takes me lots of experimentation.
On a side note....
This shorty tuned pipe is one of the best sounding setups I've had. Very mellow and powerful sounding with a dirtbike rap and no tinny weedeater noises. I think it's from the large silencer diameter and straight through construction. It is very heavy however and I still need to add a second mounting bracket for the pipe to help carry the loads. Need to settle on final engine placement first and figure out a chain adjustment system.
The engine is brand new so I cannot tell if this sweet sounding pipe will help power yet, but the engine does feel very snappy and responsive even with less than 10 miles on it.
I have seen this before with my builds. The (stock) chinagirl likes a pipe with a very short run better than long rear exit setups.
The brand new engine (Thanks to Jim Wilson at Pedalchoppers!) fired right up and off we went for a nice half hour test ride around the neighborhood. My initial impression is that this is one of the nicest chine girl powered bicycles I have ever ridden. Even though the bike itself is rather cheap and flimsy, with the motor pushing you along, it rides like a Cadillac! All the motor and intake noise you hear in a frame mount bike is behind you and inaudible. All you hear is the exhaust tone. No ringing, gear whine or tinny side cover noise at all. I'm very pleased with the first ride and am looking forward to playing with my newest toy! This is turning out better than I had hoped.
It was problem free with nothing flapping or bending. No grinding noises or ugliness to sully my very first miles. I did get some chain stretch from the cheap stock chain so I will have to redo the mount or install some kind of tensioner to get the chain right.
I'm considering a roller guide like this.
Also have a very small issue with the seat frame tapping the pipe a bit at full travel, but this will be very easy to fix by simply jacking the frame up a touch by moving the shock mounting point. Instant clearance and a slightly stiffer spring rate for ten minutes work. (This easy fix is why I was downplaying the problem to those of you who warned of interference)
Trying out the roller setup tomorrow. If it doesn't work as well as I want, I'll start working on a fully adjustable pivoting mount like the final version I've been seeing in my minds eye. This ugly hack job of scrap and bits is just a first draft.
Please believe I do nicer work than this rough prototype. This was built by me holding stuff in place and blind tacking it together, stepping back and eyeballing it, bending to suit, then welding on bits of handy scrap until it wouldn't move anymore. I have a very organic process when trying to create order out of the chaos that is my usual work area. My prototypes tend to be very ugly and disorderly looking, yet very strong for the purpose needed. I'm real good and making whatever is at hand work. Making it pretty and sleek is something that takes me lots of experimentation.
On a side note....
This shorty tuned pipe is one of the best sounding setups I've had. Very mellow and powerful sounding with a dirtbike rap and no tinny weedeater noises. I think it's from the large silencer diameter and straight through construction. It is very heavy however and I still need to add a second mounting bracket for the pipe to help carry the loads. Need to settle on final engine placement first and figure out a chain adjustment system.
The engine is brand new so I cannot tell if this sweet sounding pipe will help power yet, but the engine does feel very snappy and responsive even with less than 10 miles on it.
I have seen this before with my builds. The (stock) chinagirl likes a pipe with a very short run better than long rear exit setups.
Last edited:
Got the chain sorted and rode the wheels off the rack mount today.Added allen head capscrews and spacers to adjust chain. It's a bit tricky to reach but works quite well.
After riding it for a couple hours, everything is still nice and solid. I'll be adding some more structural braces to stiffen the rack later. I'm also going to jack up the swingarm by moving the shock mount to gain seatpost to engine clearance. 
I'm really digging this build so far. The cushy suspension and quiet engine make it very enjoyable to toodle around on! Did I mention how great the short pipe sounds? Super mellow and deep low tone. Not your average chinagirl!
Last edited:
I'm intrigued with this. As much as I like in-frame engines and especially China girls mounted that way, this is indeed a step away from the norm and an inspiration. Not something just anyone should try but certainly something to consider if a person is looking to motorize a full suspension bike.
Great work and innovation, Maniac. You've earned your username.
Thanks for sharing the build and keep us informed or further developments.
Tom
Great work and innovation, Maniac. You've earned your username.
Thanks for sharing the build and keep us informed or further developments.
Tom
As it sits now, the riding position puts far too much weight on your wrists. I bet a road bike rider would fell right at home on this bike. For me, it needs a set of high rise BMX bars to get me more upright and take the weight off my arms and wrists. This will require longer cables too it looks like. I like my seat high so that's not an issue with me. I replaced the narrow saddle with a big wide spring pan and it sits very nice. I flipped the mounting hardware to gain clearance and the pipe just barely kisses the spring when the suspension moves. Nothing banging, just a tiny rub. I'm satisfied with it right now, but looking for higher bars.
It rides so sweet! Spent another couple hours today breaking the motor in further. It just keeps getting better.
I'm tempted to do it just to see what it would sound like....
but I'm lazy and that pipe would be a pita to weld with my cheapo buzzbox welder.
but I'm lazy and that pipe would be a pita to weld with my cheapo buzzbox welder.
Wow, I really like how you fabricated your rack mount Maniac, it's like the Maserati Birdcage of rack mounts, instead of the usual angle-iron and straps commonly used, looks trick!
''Maserati birdcage'' Lol!
While I thank you for the compliment, I'm pretty sure you would get punched in Italy for slandering Maserati like that.
I used the large steel rods from a shopping cart as mounting bars, and the rear subframe from a pocketbike for the rack section. The rest is whatever steel was laying nearby as I held the engine and tacked junk to it until it was solid.
There are a couple of kit U-bolt engine mounting plates, some angle iron, and a chunk of cut off downtube.
While I thank you for the compliment, I'm pretty sure you would get punched in Italy for slandering Maserati like that.
I used the large steel rods from a shopping cart as mounting bars, and the rear subframe from a pocketbike for the rack section. The rest is whatever steel was laying nearby as I held the engine and tacked junk to it until it was solid.
There are a couple of kit U-bolt engine mounting plates, some angle iron, and a chunk of cut off downtube.
Believe me, a lot of fine Italian cars look like they were built in a backyard over a couple beers too, lol!
Have you considered using longer fuel line and mounting a tank in front of the bike like most of the in-frame designs? that tank in the back looks like it would get in the way when you're getting on the bike unless you have really really long legs
loving it maniac
glad to see you are giving the china lovers something worthwhile to consider
go man go
glad to see you are giving the china lovers something worthwhile to consider
go man go
Today I finally made the final mod for this build...I think. I jacked up the suspension by moving the front shock mount about an inch or so.
This improved clearance behind the seat and removed the need to run the seatpost up in the clouds, Overall comfort is the same but nothing clanks now during wheel travel. I also raised the steering stem for better bar position. This bike is sorted now and going on the block! Look at all the clearance from such a simple mod.
As a side note to all you builders with welders out there....
Be sure you know where your frame is grounded before welding. This cable was roasted and locked in about five seconds. The ground ran through the cable rather than the frame due to my ground clamp being on the wrong part of the frame. Instant toast!
This improved clearance behind the seat and removed the need to run the seatpost up in the clouds, Overall comfort is the same but nothing clanks now during wheel travel. I also raised the steering stem for better bar position. This bike is sorted now and going on the block! Look at all the clearance from such a simple mod.
As a side note to all you builders with welders out there....
Be sure you know where your frame is grounded before welding. This cable was roasted and locked in about five seconds. The ground ran through the cable rather than the frame due to my ground clamp being on the wrong part of the frame. Instant toast!
Last edited:
maniac
thanks for the welder ground warning!!
if you check the Buba's World posts you will see my spliced cheapie suspension bike rear to cruiser and road bike front seat posts the location of splice up and down on the seat post allows one to position not only for clearance but for wheelbase
ride safe
thanks for the welder ground warning!!
if you check the Buba's World posts you will see my spliced cheapie suspension bike rear to cruiser and road bike front seat posts the location of splice up and down on the seat post allows one to position not only for clearance but for wheelbase
ride safe
Update:
Still running great! Have not had a single issue!
Even the chain is still tight!
Can't believe this bike has not sold yet...one of my favorite builds to date!
Still running great! Have not had a single issue!
Even the chain is still tight!
Can't believe this bike has not sold yet...one of my favorite builds to date!
I can't wait to see what you do with that wheelbarrow
LOL, I knew a guy who was doing some work on his street rod and had his welder grounded to the frame. He was welding a bracket to his front axle. The suspension parts were all isolated with urethane bushings. The steel braided break lines were the only ground he had. His brake lines looked like your cables.
Tom
LOL, I knew a guy who was doing some work on his street rod and had his welder grounded to the frame. He was welding a bracket to his front axle. The suspension parts were all isolated with urethane bushings. The steel braided break lines were the only ground he had. His brake lines looked like your cables.
Tom