1984 CT70 Build - TB108,12v and a shipment from Webike...

H

HondaCTer

New Member
I've been lurking these forums for some time now and decided it was time to start a build thread of my first CT70.

A little history on my interest in minis. In 2012 I started with the purchase of a basket case 1973 ATC70. I came across it in an add for a lot sale of Honda Big Reds. $100 later I had my first project. With a lot of cleaning, painting and a new Chinese 110cc atv engine I had my first mini resto modded. It was a blast.

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In 2013 I started to hunt for a CT70. At the time I had no model year in mind, only criteria was finding a bike with paperwork in hand. After some searching I found a non-running 1984 CT70 with a Chinese 110 engine and random parts. The only remaining OEM parts were the frame, front forks, swingarm, fenders, handlebars and taillight bracket. I stripped the bike down to repaint and clean up.
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At this point I decided to swap the 110 engine from the ATC70 into the CT70 so that I could get it up and going quickly.
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H

HondaCTer

New Member
As progress continued I set up the bike as a "resto-mod" since it did not have many OEM parts.

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I ran it on the street in this trim for approximately one year. It worked well but the gearing was far from ideal as it felt like a 4 speed with third gear missing. I started to hunt for a Piranha 140.... It turned out to be an excellent swap and the power was awesome. The only issues were the lack of a decent stator to power lights and a carburetor that was not dialed in. I found a cheap enduro headlight and swapped an led bulb into it for a bit more light.

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The one piece cheap cast aluminum Chinese wheels were light weight but I often questioned how strong the locking ring grove was. I decided to start searching for another CT70 to build as a beater and to find more original 80's parts for this bike.

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After some searching on Kijiji I came across a stripped down 1982 and an almost complete 1986. In between pickups I was able to find an almost complete Z50 engine and another set of cases.

Work started with swapping over an original set of wheels on my 1984....

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H

HondaCTer

New Member
I thought it would be interesting to build up the original CT70 engine in the 1986 with a full TB Parts 88cc kit. So I started to strip down the motors to see what I had.....

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Turned out the crank was shot and the oil pump went on vacation some time ago. This was going to require a full rebuild..... TB Parts 108 it is.....

After accumulating various Chinese engine I save a 12v stator and flywheel, so I decided to go with the 12v stroker crank. The kit was ordered and a second large order from Webike Japan for various items that I needed and wanted. Fast forward three years I was overcome with extra hours at work and was unable to finish the build.

I decided to cut down on the hoard, save the CT70 engine for my bike, swap the Piranha 140 into the 1986 chassis and sell it. At the same time I sorted out all of the original parts that I needed for spares and sold the balance including the 1982 frame.

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Once everything was sold off I started work on the CT70 engine for my 1984.
 
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H

HondaCTer

New Member
Clearance for the 12v stator....

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New bearings...

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Checked the transmission and found that the shift forks were worn. Fortunately I had a set from the Z50 engine that were almost like new.

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I drilled out the oil passage for the high volume oil pump and started assembly....

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H

HondaCTer

New Member
More shots of the engine mid assembly. Takegawa HD clutch and high volume oil pump.

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Cleaning up some more parts....

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Studs in prepping for cylinder and piston. Had to change one as the threads were damaged. Nice having some spare parts on hand. New OEM cam chain idler wheel and oil pump gear.

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H

HondaCTer

New Member
I'm struggling tonight to upload some pictures tonight. I keep receiving error messages....

After some waiting for seals and a spring that I was missing between the clutch cover and the clutch I was able to finish up the clutch side and top end.

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The kit from TB Parts is nicely finished and looks great. Kitaco cam gear installed and waiting to adjust the valves. 12v stator and plate from a Lifan 140 that I salvaged some time ago.

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kirrbby

kirrbby

Well-Known Member
Lookin REALLY good. You even popped for the race head.
Did you polish up that clutch cover yourself. It looks great. I think that look is cleaner, and nicer, than a quality paint job. Was it done by hand?
 
H

HondaCTer

New Member
kirrbby said:
Lookin REALLY good. You even popped for the race head.
Did you polish up that clutch cover yourself. It looks great. I think that look is cleaner, and nicer, than a quality paint job. Was it done by hand?
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Thanks!!! I painted engine covers before, but, always had to deal with scuffing and wear. I thought this time I would go for a brushed/polished look. The previous owner painted them black so I sanded them down and went over them to take out any nicks with 180, 220 and finished with 400. I'm happy with the final product.
 
H

HondaCTer

New Member
kirrbby said:
Lookin REALLY good. You even popped for the race head.
Did you polish up that clutch cover yourself. It looks great. I think that look is cleaner, and nicer, than a quality paint job. Was it done by hand?
Click to expand...

Sorry missed a part of the reply. Yes, all polishing and cleaning was done by hand with assistance of a Dremel for the tight areas. Quite a few hours were consumed trying to get things as smooth as possible.
 
H

HondaCTer

New Member
I will have to skip the rest of the engine build photos for now as they are not uploading.

Since I did the 12v swap the original stator cover would not fit. I had the cover from the 140 Lifan that I salvaged, but, did not find that it looked "original". Before swapping the Piranha 140 to sell I grabbed the original cover off of it, saved a Honda derby cover and grafted the two together. Little bit of sanding, drilling, grinding, polishing, high strength Loctite and JB Weld.....

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Before selling the 1986 CT I salvaged the full wiring harness, dash, speedo and key. I also have the original harness for the Lifan 140 including the CDI and coil. I clean everything up and will work on labelling the OEM harness. Some wires were cut and the left hand control's light switch was damaged. I have a second unit that is complete fortunately. I will work on stripping, cleaning and testing these controls next.

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6

69ST

Well-Known Member
I like your flywheel cover solution, very clean. The alternative is fabbing spacers for a 6v cover, which is far more involved and only a matter of cosmetics. This thing ought to rip.
 
H

HondaCTer

New Member
racerx said:
I like your flywheel cover solution, very clean. The alternative is fabbing spacers for a 6v cover, which is far more involved and only a matter of cosmetics. This thing ought to rip.
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Thank you! I thought about the spacers and decided this would be the easiest route given I had the cover.
 
H

HondaCTer

New Member
Adam-NLV said:
Luv your work! (y) That's the build i always thought about doing but never did. Yours looks Great!:red70:
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Thank you!!! It means a lot. I'm happy I did not rush this one. It does not compare to the caliber of some of the builds on this site, but, my hopes are that it will be something a little different. More of a resto-mod.... plus the 80's CT70s were more of the red headed stepchild.
 
6

69ST

Well-Known Member
HondaCTer said:
Thank you!!! It means a lot. I'm happy I did not rush this one. It does not compare to the caliber of some of the builds on this site, but, my hopes are that it will be something a little different. More of a resto-mod.... plus the 80's CT70s were more of the red headed stepchild.
Click to expand...

There is some truth in that. Fact is, they all share the same dna. The most noticed changes were cosmetic. What escaped notice were the mechanical improvements. The '80s era bikes had some good upgrades...they were essentially the same as the '90s versions, but lacking 12v CDI.

Once a bike is customized, model year matters less...except for regulatory requirements, i.e. insurance & required lighting.
 
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