Loncin 4-stroke, Nuvinci, Stretch Frame

GoldenMotor.com

i-paint

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May 24, 2008
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This was my winter project I recently finished. We've had a few warm days so I had a chance to test it. Very smooth, cruises nicely around 40 mph. Top speed (checked with car speedometer) was 53 mph. I believe it will do better as it gets broken in. The engine is a 70CC. It was way less than a Honda or the Chinese 4 strokes. My Nuvinci hub won't last long I'm afraid using these speeds and torque. It sometimes skips when it gets hot after a long run. I have about 75 miles on the bike by the way. I twisted the axle in the dropouts using one set of locks. I have two on each side now and that seems to be holding. The chain tensioners in the picture have lockout washers that fit over the axle and in the slot as well as one on the outside to keep it from twisting. The twin disc brakes on the front are an improvement over the single but I would like for them (the pads) to be bigger. I will continue to work on this one trying to get more speed and maybe play with some lighting.

PS I know the chain from the engine to the jackshaft is a little loose. I changed the sprocket and didn't tighten it. The sprocket on the engine "floats" back and forth to keep the chain perfectly in line so it doesn't want to come off anyway.
 

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Crazy Horse

Dealer
Feb 20, 2009
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i-paint, this build is amazing especially since it's a Stretch Cruiser ( Micargi ? ), I've been slow to complete my stretch cruiser ( Greenline ) with a 110cc lifan horizontal 4-stroke semi-automatic s
For others interested these motors are all copies of the old Honda CT 70 Trail Bike & Honda 50 Mini Trail Bikes.

I originally started my build in July 2009 using the Greenline Stretch Cruiser with an extra 110c motor from a hardknock bobber but had to delay it, hopefully it'll be rideable soon!

I'll post a couple of pic's here of the old Honda Trail Bikes showing this type of horizontal 4-stroke same used on hardknock bobber's, so that others can have a better idea of where these motors came from and how they are so practical for Stretch Cruiser builds.

i-paint, maybe you can share with us more details about your build, how did you mount your motor to the frame, where'd you purchase your motor from, is your motor fully automatic, how much $$$ invested in this build so far, how many hours wrenching to date, etc etc...

My hardknock bobber does almost 60mph i'm a lil bit intimidated as for how fast my Stretch Crusier go I'll guesstimate close to 60 or more miles per hour!!!

IMO you will definitely destroy that nuvinci hub using your 4-stroke loncin motor.

Keep up this amazing work with your Stretch Cruiser, your work will inspire others to be sure!!!




Peace C.H.

First two pic's are yellow 1968 Honda Mini Trail Z-50, 1969 Red Honda Mini Trail Z-50, 3rd pic is 1970 Honda CT 70 Trail Bike, 4th pic is my hardknock bobber 110cc right side, 5th pic my 110cc bobber check out that shifter.
 

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i-paint

New Member
May 24, 2008
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Crazy Horse, I originally mounted a Lifan 125CC 4 speed in this frame but decided I didn't want to have two tramsmissions. I dont think the Lifan would fit in the Greenline stretch I had before this one, at least not level. I have a slotted plate welded to the frame the engine sits on. Four bolts on the bottom of the engine attach it to the plate and it adjusts back and forth. One of the pictures shows this as well as the chain tensioner I am using on the engine. The torque on the engine chain tries to pull the engine back and loosens the chain. I don' keep very close records of what I have in the bikes and use a lot of the parts over. The engine was a $139.00 special I bought from High RPM Racing Online Store. I do believe it is a quality part comparatively.
 

i-paint

New Member
May 24, 2008
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I love it!!! (^)
How did you make the dual disc brake??
I bought the hub and calipers from Choppers R Us. I had the hub machined to accept the sealed bearings. To mount the calipers I duplicated the bracket on the left fork that I had. I taped the two fork tubes together and used bolts through the existing bracket into the loose one. Using the bolts and nuts to achieved the correct placement of the loose bracket, I welded it to the right fork.
 

Venice Motor Bikes

Custom Builder / Dealer/Los Angeles
Mar 20, 2008
7,266
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Los Angeles, CA.
I bought the hub and calipers from Choppers R Us. I had the hub machined to accept the sealed bearings. To mount the calipers I duplicated the bracket on the left fork that I had. I taped the two fork tubes together and used bolts through the existing bracket into the loose one. Using the bolts and nuts to achieved the correct placement of the loose bracket, I welded it to the right fork.
Cool! Can you post some pics?? :D
 

Crazy Horse

Dealer
Feb 20, 2009
1,153
3
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USA
Crazy Horse, I originally mounted a Lifan 125CC 4 speed in this frame but decided I didn't want to have two tramsmissions. I dont think the Lifan would fit in the Greenline stretch I had before this one, at least not level. I have a slotted plate welded to the frame the engine sits on. Four bolts on the bottom of the engine attach it to the plate and it adjusts back and forth. One of the pictures shows this as well as the chain tensioner I am using on the engine. The torque on the engine chain tries to pull the engine back and loosens the chain. I don' keep very close records of what I have in the bikes and use a lot of the parts over. The engine was a $139.00 special I bought from High RPM Racing Online Store. I do believe it is a quality part comparatively.
I-Paint, thanks for the lead at High RPM Racing at: Loncin Engine - 110cc Dirt Bike - $139 SPECIAL 70cc Engine Complete - Full Auto - No Reverse - $139.00 - HighRpmRacer.com

I talked to Devin at High RPM Racer he has plenty of these motors which can be ordered with wiring harness & handlebar-control switches for lights, turn signals & brake lights, horn, keyed ignition, cdi module, the works!!!

I just posted on your original thread for this build, I'm curious about your combination motor mount & jackshaft freewheel can you please share with us Stretch Cruiser builders details of this setup for the 50cc/70cc loncin 4-stroke horizontal motor did you make any adjustments from the Lifan 125cc mounting & jackshaft?

Peace Crazy Horse
 

i-paint

New Member
May 24, 2008
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I-Paint, thanks for the lead at High RPM Racing at: Loncin Engine - 110cc Dirt Bike - $139 SPECIAL 70cc Engine Complete - Full Auto - No Reverse - $139.00 - HighRpmRacer.com

I talked to Devin at High RPM Racer he has plenty of these motors which can be ordered with wiring harness & handlebar-control switches for lights, turn signals & brake lights, horn, keyed ignition, cdi module, the works!!!

I just posted on your original thread for this build, I'm curious about your combination motor mount & jackshaft freewheel can you please share with us Stretch Cruiser builders details of this setup for the 50cc/70cc loncin 4-stroke horizontal motor did you make any adjustments from the Lifan 125cc mounting & jackshaft?

Peace Crazy Horse
No changes to the engine mount. These engines are like the Morini two-stroke. There are several models, different CCs, which use the same base. They only change the cylinder and head (sometimes) to get diferent CCs. The 50 and the 70 have the same stroke but different diameter pistons. The 90 and the 110 are the same way. A 110CC will fit on the same mounting as a 50CC. However the stroke is shorter on the 70CC than the 125CC and the cylinder is shorter. This moved my exhaust pipe toward the rear of the bike about an inch or so and I had to rework the bracket that holds the end of the pipe. This is the only change I made. The jackshaft is in a pipe with a machined i.d. to accept the 5/8 bearings. The reason for the freewheel on the crank chain end of the jackshaft is so the crank chain doesn't turn when when under power. The only reason for the freewheel on the crank is to attach the chain wheel. If you have a crank with the proper size chain wheel the freewheel isn't needed. The freewheel on the engine side driven sprocket is so when you pedal the engine chain doesn't turn making it a lot easier to pedal. There is another freewheel on the hub. I have included a picture of the mount which is supposed to be equal to a thousand words more or less. i-paint
 

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i-paint

New Member
May 24, 2008
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No changes to the engine mount. These engines are like the Morini two-stroke. There are several models, different CCs, which use the same base. They only change the cylinder and head (sometimes) to get diferent CCs. The 50 and the 70 have the same stroke but different diameter pistons. The 90 and the 110 are the same way. A 110CC will fit on the same mounting as a 50CC. However the stroke is shorter on the 70CC than the 125CC and the cylinder is shorter. This moved my exhaust pipe toward the rear of the bike about an inch or so and I had to rework the bracket that holds the end of the pipe. This is the only change I made. The jackshaft is in a pipe with a machined i.d. to accept the 5/8 bearings. The reason for the freewheel on the crank chain end of the jackshaft is so the crank chain doesn't turn when when under power. The only reason for the freewheel on the crank is to attach the chain wheel. If you have a crank with the proper size chain wheel the freewheel isn't needed. The freewheel on the engine side driven sprocket is so when you pedal the engine chain doesn't turn making it a lot easier to pedal. There is another freewheel on the hub. I have included a picture of the mount which is supposed to be equal to a thousand words more or less.
I would like to clarify that the $139.00 70CC engine is basic with the intake manifold as the only accessory. You will need a carburetor, cdi, coil, rectifier, starter relay, battery, some type of starter switch, kill switch and exhaust. These parts will add another $2-300 at least by the time you add shipping. i-paint
 
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Crazy Horse

Dealer
Feb 20, 2009
1,153
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36
USA
No changes to the engine mount. These engines are like the Morini two-stroke. There are several models, different CCs, which use the same base. They only change the cylinder and head (sometimes) to get diferent CCs. The 50 and the 70 have the same stroke but different diameter pistons. The 90 and the 110 are the same way. A 110CC will fit on the same mounting as a 50CC. However the stroke is shorter on the 70CC than the 125CC and the cylinder is shorter. This moved my exhaust pipe toward the rear of the bike about an inch or so and I had to rework the bracket that holds the end of the pipe. This is the only change I made. The jackshaft is in a pipe with a machined i.d. to accept the 5/8 bearings. The reason for the freewheel on the crank chain end of the jackshaft is so the crank chain doesn't turn when when under power. The only reason for the freewheel on the crank is to attach the chain wheel. If you have a crank with the proper size chain wheel the freewheel isn't needed. The freewheel on the engine side driven sprocket is so when you pedal the engine chain doesn't turn making it a lot easier to pedal. There is another freewheel on the hub. I have included a picture of the mount which is supposed to be equal to a thousand words more or less. i-paint
I-Paint could you please do a break down build list of how who what where, etc for this build ?

Here are links showing other stretch & chopper build list break downs.

Here is RedB66's break down of his Stretch Cruiser Build list:http://motorbicycling.com/f40/sneak-peek-orange-crush-16116.html

Sneak Peek at "Orange Crush"

The frame is from Masterlowrider.com
Tank is custom from ACME Labs
66cc Slant head with chrome covers
Husky 12ga wheels with Manic Mechanic 28T
Handlebars are 780mm Super Wide Cruiser
Fenders are Nirve Street Sweepers
The mounts are a evolution from my original idea.
Updated "Stretch" cruiser mounts



As stated by Graucho in his chopper build list post:http://motorbicycling.com/f40/fat-tire-bicycle-chopper-6778.html

Fat Tire Bicycle Chopper!
When I see other peoples builds I always ask myself...."self" where did he get that item? Well, i'm not going to leave anybody out there hang'in with that question. I hope this helps someone if they need a similar part that I have used on my bike. I used to have better tools but I got rid of them when I thought I was getting out of building. (wrong) since, I bought a lot of stuff "on the cheap" and they have worked out just fine. Take care and thanks for your kind words everyone. graucho


Another member Civlized showed us his break down build list too: http://motorbicycling.com/f40/atv-50cc-full-auto-stretch-13417.html

ATV 50cc Full Auto on a stretch!
Thanks guys! It really makes all of the griping I get from the old lady worth it when you say stuff like that.

Here's the list I came up with. If I left something out, sorry. Please ask if you have any questions.


Many thanks to you I-Paint, AzBill, Civlized, Graucho, and last but not least RedB66 regarding the how you did it, where you bought it, what you built it with etc.. etc...You Guy's Are The Rock Stars of Stretch Cruisers & Choppers, there are many others whom, I did not mention that inspire all of us in the Stretch Cruiser & Chopper build Genre!!!


Thanks again for sharing with all of us your outstanding skills, talent, and experience with your Custom Stretch Cruiser's & Chopper Motor-Assisted builds they are all works of art!!!

Rock on I-Paint

Peace Crazy Horse.
 

i-paint

New Member
May 24, 2008
136
1
0
I-Paint could you please do a break down build list of how who what where, etc for this build ?

Here are links showing other stretch & chopper build list break downs.

Here is RedB66's break down of his Stretch Cruiser Build list:http://motorbicycling.com/f40/sneak-peek-orange-crush-16116.html

Sneak Peek at "Orange Crush"

The frame is from Masterlowrider.com
Tank is custom from ACME Labs
66cc Slant head with chrome covers
Husky 12ga wheels with Manic Mechanic 28T
Handlebars are 780mm Super Wide Cruiser
Fenders are Nirve Street Sweepers
The mounts are a evolution from my original idea.
Updated "Stretch" cruiser mounts



As stated by Graucho in his chopper build list post:http://motorbicycling.com/f40/fat-tire-bicycle-chopper-6778.html

Fat Tire Bicycle Chopper!
When I see other peoples builds I always ask myself...."self" where did he get that item? Well, i'm not going to leave anybody out there hang'in with that question. I hope this helps someone if they need a similar part that I have used on my bike. I used to have better tools but I got rid of them when I thought I was getting out of building. (wrong) since, I bought a lot of stuff "on the cheap" and they have worked out just fine. Take care and thanks for your kind words everyone. graucho


Another member Civlized showed us his break down build list too: http://motorbicycling.com/f40/atv-50cc-full-auto-stretch-13417.html

ATV 50cc Full Auto on a stretch!
Thanks guys! It really makes all of the griping I get from the old lady worth it when you say stuff like that.

Here's the list I came up with. If I left something out, sorry. Please ask if you have any questions.


Many thanks to you I-Paint, AzBill, Civlized, Graucho, and last but not least RedB66 regarding the how you did it, where you bought it, what you built it with etc.. etc...You Guy's Are The Rock Stars of Stretch Cruisers & Choppers, there are many others whom, I did not mention that inspire all of us in the Stretch Cruiser & Chopper build Genre!!!


Thanks again for sharing with all of us your outstanding skills, talent, and experience with your Custom Stretch Cruiser's & Chopper Motor-Assisted builds they are all works of art!!!

Rock on I-Paint

Peace Crazy Horse.
CH, I honestly do not know the names of most of the businesses I bought from. I don't keep receipts. I don't want to. Enough of that in business. Most of my parts come from the internet.
My wheels were built at a bike shop in IN. I bought the engine and related parts mostly from High RPM. The Nuvinci hub is from Stanton. (It is wasted by the way. I don't recommend it for this engine. I'm going back to my Nexus 8 speed.) I bought the gas tank on ebay. I think the seat is from Bike World Online. i-paint
 
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BarelyAWake

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Jul 21, 2009
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...It (Nuvinci) is wasted by the way. I don't reccomend it for this engine. I'm going back to my Nexus 8 speed...

More info on this please if you can bear to tell the sad tale, many dream of the Nuvinci & a shift kit - even I have kept it in mind as a replacement/upgrade should my Sturmy fail me...

The $300 price tag kinda excludes many frm wanton experimentation however. Didja perform a postmortem?
 

i-paint

New Member
May 24, 2008
136
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More info on this please if you can bear to tell the sad tale, many dream of the Nuvinci & a shift kit - even I have kept it in mind as a replacement/upgrade should my Sturmy fail me...

The $300 price tag kinda excludes many frm wanton experimentation however. Didja perform a postmortem?
BW, It is possible I have a bad hub but I doubt it. I contacted Nuvinci to explain the condition of my hub and to ask if it could be repaired. The engineer that responded read me the riot act and said the application I had used the hub for was equal to child abuse (He really didn't say that last part). He did say however the hub wasn't designed to be used with an engine such as I have. He said they couldn't warranty the hub having used it as I did. I told him I didn't expect them to warranty it I just wanted to know could it be repaired. He said I must have broken something inside the hub (duh!) and it couldn't be repaired. They sent me a test hub for a reduced price. I have no plans of using the new hub. He wants me to send the old one back for their examination. I don't know if I will send it back, I don't think I will. He also said the hubs were sealed and could only be opened by their technicians with special tools. It is still on the bike now but I am building another wheel with a Nexus hub. When I change the wheels I am going to take the old Nuvinci apart.

I had the Nuvinci on a stretch bike with a Morini 8-9 hp engine. It performed well for several hundred miles. When I switched the hub to the stretch with the Loncin it soon failed. The Loncin has much more low end torque than the Morini, probably is the difference, plus the bike with the Loncin is much heavier. On a standard bike with a less powerful engine the Nuvinci may last a long time. In my experience and the torture I put these hubs through, the Shimano Nexus is better. The Nexus 8 speed "Red Band" or premium hub is very strong and can be bought for less than $200.00 shipped.

i-paint
 

BarelyAWake

New Member
Jul 21, 2009
7,194
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Maine
I'm sorry that the Nuvinci kicked it, but the info gained is invaluable - although I've no intent on runnin' even half your HP it's great to know what'll put up with it!

Nexus 8 speed "Red Band" you say? hmmm... I'll hafta remember that, thanks ;)
 

benjiblood

New Member
Jun 13, 2011
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Downriver
hey, i have a 4-stroke loncin 50cc semi-auto. and i cant find anything for it. i cant even find a decent source on google. could you help me out by sending me some web addresses or anything. i might need a new carb for mine. but dont even know where to start.
 

camlifter

Active Member
May 4, 2009
1,033
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acme labs marion ohio
heres a link to the inner workings of the nuvinci. i did get my hub working again and now use it on a normal pedal bike. no motor. the long bail spring that is wound inside the drive drum slips out of it's slot and stops the hub from working when to much power is put to it. not hard to fix. a china girl seems to be ok with the hub but much more than that amount of power pops the spring out. theres a lot of good info in the thread.http://motorbicycling.com/showthread.php?t=21827