New Member, first build. 80cc china girl on a fixie
- Thread starter jerrywelz
- Start date
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piecepatrol99
Member
Sorry to hear your bike was stolen. Especially after you put so much work in to it. I'm ****ed just hearing about it...
Some added salt for me is I now have the same bike with a slightly different paint job.
I've read the entire thread. I have to give thanks to all that posted and commented as I found much info on tuning my motor for better peformance.
The black bike is the Ocean Pacific beach cruiser from walmart. Installed is a 49cc china girl. Got about 300miles out of the bike when the fork broke in the head. I thank God it wasn't a clean brake or I may not be here to make this post. I was doing about 30 when I rode over a recessed manhole cover and felt the hole bike drop.
Took it back to wallyworld (after returning it to stock) and exchanged it for the Kent.
Unfortunately, the 7 speed internal hub I had on the cruiser is too wide (locknut to locknut) for the fix chainstay.
I installed the motor with jackshaft kit on the Kent thinking: "now I can bump start the bike instead of having to pedal".
Nice idea but it didn't work for long. The fix cog unscrewed from the hub and just pushed the lockring off. I flipped the wheel to the freewheel side to get to the bike shop. Harry Bridger is a great guy. I didn't know 3 speed freehubs were available til I got to him.crying for help. I've ordered one and it should be here in the next 5 hours or so...
In the mean time, I'm.looking in to installing another chainring on the.freewheel crank for a high.low rang (wether the freehub fits or not). The 18T that comes on the wheel is no good with my 280lb frame. I need gears for the small mountains I travel the some 25miles it takes for me to get into the city.
I'm thinking at the very least I'll have a 30T low and 40T high on the pedal crank. And if the freehub fits even better
My to do list:
I've cut a 2 1/2" length of aluminum stock to mount the rear deraileur. The bike has a horizontal dropout and the dreaileur is for a vertical. I'm going to drill 6 holes total. 2 in the DR and 4 in the stock. 2 5mm grade 8 bolts will hold the stock to the CS forward of the axel and below the slot. 2 more bolts will hold the deraileur to the stock and in position. It will be. Used only as a chain tensioner as I'm still waiting for the radip fire shifters to be shipped.
On a side note, it puzzling that they're both coming from china. Were ordered only three days apart, but the shifters are taking a week longer just to get moving...
Its 5:30am and I can't sleep. I'm just waiting for 6 so I can go start drill holes and my nieghbors won't be able to complain.
Next will be removing the right crank arm and star choosing which CR's to use to drive the back wheel. After I fugure out which CR I can get away with from the JS to the outer CR.
I'm a little concerned with the mention I saw about frame cracks. There's one spot (right side seatstay/seattube) that I'm really not liking how thin the paint looks and how sharp it feels...looks like I'll be trying out my wire welder soon.
One thing I learned when the JS kit was on the aluminum framed cruised is to reinforce the the frame. After a few hours of cutting pipe and hammering it down the seat tube because the pipe clamps/JS motor mounts were cutting the tube, I've given the Kent the same treatment. Cut the slender ends off seat post and dropped them down the tube before I have any 'crushing' issues.
I found the crushing issue when I pulled the motor to put it in another bike. I can't describe how disappointed I was to find out it wouldn't fit the frame. Even without the JS kit. Motor head was into the top tube about 3".
I really need to take more pics. I have three head light installed. A rear rack with tail/brake lights and turn signals waiting ti be rinstalled and three taillights waiting to be installed.
If its not one thing its another...
Wanted to put the motor in the Mongoose but it doesn't fit.
While the motor was out of the OP, found the damage that could have been catastrophic, fixed it, was confident that nothing else would/could go wrong (I replaced chains and JS bearings twice due to alignment issues) and the fork breaks.
Fet th flip flop fix and the fix sprocket falloff the first day...
Seems like I'm living to turn wrenches...if only I got paid for it...
But I'll get this the way I want it. Hopefully before I need studded tires ;-)
piecepatrol99
hey man, i'm glad this thread and all who shared was a help to you.
Your bikes look well put together! i see you've got the boost bottle, running an aftermarket CDI? I've heard people claim the NT carb is king, but i really like a properly jetted SHA carb. It gives the throttle a better twist and every one i've come across has a plastic sleeve that solves intake air leaks.
Anyway, our engines are all about the pipe. haha, an expansion chamber will wake your bike up in a major way. My friend with the beach cruiser claimed he had better longevity with the 49cc HT.
I'm glad you got your wheel, and hub stuff sorted. sounds like you have some great ideas brewing. i've shyed from the jack shaft due to my love of simplicity. the china girl can do 45+ with 36t sprocket and some mods.
I feel you on the wrenching thing. thanks for sharing man, keep us posted!
Some more details:
Fito Modena EX frame
PK80 china girl (better than first one i bought)
couple manic mechanic, intake manifold and sprocket/adapter
dual pull break, working flip kill switch, billet throttle
#41 go kart chain
got a few lights, reflectors, sinter fuel filter, comfy seat, bigger wheels
can't wait for my 4th, gonna go balls out 4 stroke
hey man, i'm glad this thread and all who shared was a help to you.
Your bikes look well put together! i see you've got the boost bottle, running an aftermarket CDI? I've heard people claim the NT carb is king, but i really like a properly jetted SHA carb. It gives the throttle a better twist and every one i've come across has a plastic sleeve that solves intake air leaks.
Anyway, our engines are all about the pipe. haha, an expansion chamber will wake your bike up in a major way. My friend with the beach cruiser claimed he had better longevity with the 49cc HT.
I'm glad you got your wheel, and hub stuff sorted. sounds like you have some great ideas brewing. i've shyed from the jack shaft due to my love of simplicity. the china girl can do 45+ with 36t sprocket and some mods.
I feel you on the wrenching thing. thanks for sharing man, keep us posted!
Some more details:
Fito Modena EX frame
PK80 china girl (better than first one i bought)
couple manic mechanic, intake manifold and sprocket/adapter
dual pull break, working flip kill switch, billet throttle
#41 go kart chain
got a few lights, reflectors, sinter fuel filter, comfy seat, bigger wheels
can't wait for my 4th, gonna go balls out 4 stroke
piecepatrol99
Member
You're welcome for the help and at the same time, thankyou
Imagine if you will this forum being like getting a flat tire. Instead of every car just whizzing by, everyone stops to lend a hand and get you back on your way. Not only that, but the posts are like the tools being left behind for the next troubled cyclist.
Knowledge being power, just seeing/hearing some one elses idea or train of thought solves what perplexes ones nieghbor...
I'm probably off topic for this forum but I'm gonna have at it any way...
This is my 'rebuilt' front freewheel. It has0 30, 36 and 48 tooth chainrings. I have now made my flip flop fix a 2 speed with the addition of front and rear deraileurs.
Tho the rear for now is only serving the purpose of chain tensioner, I have a 3speed freehub waiting to replace the the single speed. That will be done as soon as the shifter comes in and I can get to the bike shop to have the freewheels swapped ;-)
A few things I ran in to...
The 30, 36, 48 combo is going to be changed to 36, 44, 48. Reason is that it is difficult to shift into high gear. The deraileur hits the inside of the 48T.
I had to cur the deraileur to get it to fit between the chain coming off the jackshaft only to have it collide with the CR it self. No big deal, another 30 minutes work...
While the front deraileur was a direct bolt on (short of cutting 1/2" off the back and moving the rear roller forward that much) the rear presented a little more of a challenge.
I cut a 2" length of aluminum stock (1"Wx1/4"T available at Lowes, HomeDepot...) to mount my vertical dropout deraileur to my bike with horizontal dropout. Only one hole was drilled in the chainstay/dropout. The next hole was drilled so the head of the bolt is in the dropout slot locking the stock in place. The deraileur is mounted to the stock in similiar form. Drilled a hole in the stock and bolted the D through the hole it would have been mounted. And a hole was drilled in the stock placing the head of the bolt in the DR slot of the D to keep it from moving out of position from motor virbration and chain tension.
Now instead of pulling back on the wheel to tension the chain, I just tighten the right lug where I want it and align and lock it with the left.
ATTACH]
I did use some if not all of the carpenters three rules...
1: Measure twice, cut once.
2: Measure twice, cut once.
3: If it don't fit, force it!
I did also have to install a spacer to the right bearing cup. The nylocks of the chainring hardware were 'touching' the chainstay behind the bottom bracket.
Now that I mention that, I may not be able to use the 36T as my smallest CR. The 30 is that close to the CS already :-\ I'll have to take another look at it...
Imagine if you will this forum being like getting a flat tire. Instead of every car just whizzing by, everyone stops to lend a hand and get you back on your way. Not only that, but the posts are like the tools being left behind for the next troubled cyclist.
Knowledge being power, just seeing/hearing some one elses idea or train of thought solves what perplexes ones nieghbor...
I'm probably off topic for this forum but I'm gonna have at it any way...
This is my 'rebuilt' front freewheel. It has0 30, 36 and 48 tooth chainrings. I have now made my flip flop fix a 2 speed with the addition of front and rear deraileurs.
Tho the rear for now is only serving the purpose of chain tensioner, I have a 3speed freehub waiting to replace the the single speed. That will be done as soon as the shifter comes in and I can get to the bike shop to have the freewheels swapped ;-)
A few things I ran in to...
The 30, 36, 48 combo is going to be changed to 36, 44, 48. Reason is that it is difficult to shift into high gear. The deraileur hits the inside of the 48T.
I had to cur the deraileur to get it to fit between the chain coming off the jackshaft only to have it collide with the CR it self. No big deal, another 30 minutes work...
While the front deraileur was a direct bolt on (short of cutting 1/2" off the back and moving the rear roller forward that much) the rear presented a little more of a challenge.
I cut a 2" length of aluminum stock (1"Wx1/4"T available at Lowes, HomeDepot...) to mount my vertical dropout deraileur to my bike with horizontal dropout. Only one hole was drilled in the chainstay/dropout. The next hole was drilled so the head of the bolt is in the dropout slot locking the stock in place. The deraileur is mounted to the stock in similiar form. Drilled a hole in the stock and bolted the D through the hole it would have been mounted. And a hole was drilled in the stock placing the head of the bolt in the DR slot of the D to keep it from moving out of position from motor virbration and chain tension.
Now instead of pulling back on the wheel to tension the chain, I just tighten the right lug where I want it and align and lock it with the left.
ATTACH]I did use some if not all of the carpenters three rules...
1: Measure twice, cut once.
2: Measure twice, cut once.
3: If it don't fit, force it!
I did also have to install a spacer to the right bearing cup. The nylocks of the chainring hardware were 'touching' the chainstay behind the bottom bracket.
Now that I mention that, I may not be able to use the 36T as my smallest CR. The 30 is that close to the CS already :-\ I'll have to take another look at it...
Attachments
piecepatrol99
Member
If I can't go from 30, 36 to 36, 44 to stop the D from hitting the 48 due to the 36 hitting the CS: I'll have to swap the 48 for the 44 to get the clearance I need between the D and the outer CR.
Sometimes "The Carpenters Three Rules" will only work if you're willing to go balls out crazy. Cutting a notch in the CS and welding a gusset in for clearancing the 36T are steps I don't believe are worth the effort for the resulting gear ratio.
If I really wanted to gear my bike for top end, I'd use my 24T as the outer CR! Lmbo!!
Sometimes "The Carpenters Three Rules" will only work if you're willing to go balls out crazy. Cutting a notch in the CS and welding a gusset in for clearancing the 36T are steps I don't believe are worth the effort for the resulting gear ratio.
If I really wanted to gear my bike for top end, I'd use my 24T as the outer CR! Lmbo!!
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