CT90 Resto-Mod

W

WonderMuscle

Member
Well LilHonda.... I'm back! After a year hiatus playing with a Honda Grom I've started my CT90 resto-mod project. I plan to make a CT90 that will cart me around town and look good while doing so. My CT70 would do 75mph and I'd like this CT90 project to do 80MPH. I started with a very rough around the edges 1974 that came with a side car. I bought the entire setup for $400 nearly 2 years ago. I don't have a picture of the pair when I bought them, something about losing my phone... This is the CL add picture of the side car, the sidecar is in the process of being restored to working order.

ct90sidecartpic2.jpg

Here is a link to my CT70 project which I sold to buy a Grom. I had the Grom for a year and lost interest as it wasn't as fun as the CT70 nor did it have the allure. http://lilhonda.com/webboard/f14/wonders-ct70-build-15337/

I have built a 126cc honda motor from an ATC125M crank, ATC110 cylinder and an ATC125M piston. I had to machine the crank to fit the CT90 cases and the dome of the piston so they wouldn't hit the valves. Finding a cam chain that was the correct length was the most difficult part. This motor is finished and sitting on my tool bench waiting to get put in the bike. This will happen next week, I hope... i will probably run this motor for a few months and once proven I'll likely put it up for sale. I will then buy a Daytona 190 Anima FLX and modify the frame to fit the motor.

I have a klx140L front end with a KX85 front wheel and disk. The bike currently sits all choppered out since the forks are about 3" too long. I will cut these down once I have the rear wheel built. Here is how she currently sits.

20141003_185336.jpg

20141003_185344.jpg

I have a 2.75" x 17" rear rim on order which will get wrapped in a 110/990-17 Michelin pilot sport and the front wheel will get wrapped in a 90/90-17 IRC, 90/90's are hard to find. I am going to powdercoat the rims/hubs black as well as some other bits.

The frame will get the rear fender flared and all the unused holes welded up and finished flush. I'll eventually powdercoat the frame pearl white.

Russ
 
W

WonderMuscle

Member
I have torn the bike mostly apart and sent the rims, hubs, triple clamps and other bits to the powdercoater. They should be done in a week or so. In the mean time I will be re-wiring the bike with a new harness from the guy on ebay. I'll pull the forks apart and cut the upper fork tubes down by 2.5" on the lathe. Baby Steps...

Here is a picture of the side car with new frame hooked to my friends CT110. He is has taken it upon himself to fix 'er up.

IMG_9144.jpg
 
W

WonderMuscle

Member
I have made a bit more progress over the weekend. I managed to remove the old wiring harness and install a new one. I hope this solves a short I had with the turn signals. Time will tell.

I also got all my powdercoated parts back and laced up my new wheels. The KLX140L is back to it's original glory but with a black hub and black rim. The rear is a 2.75" sun rim with the stock hub and Buchanan spokes. It had been years since I laced up on these old rims. I fumbled around with the inner and outer spokes but it managed to true up nicely. I should have tires mounted up Tuesday.

IMG_20141109_163243.jpg
 
W

WonderMuscle

Member
Finally Getting Somewhere

I finally got some time to work in the garage over the past few days and have made some good progress. The wife had me putting in pavers and building fences around the house. I cut down the KLX140 front forks and re-threaded them for the top plug. I managed to integrate new switches, turnsignal/brakelight and complete the wiring with some helpful advise from Mel. The wiring still needs to be cleaned up but it is at least all figured out for now. I installed my 126cc homemade Honda motor which does run, I currently don't have a working throttle cable. I need to adjust the offset of the rear rim on the hub as you can see it doesn't sit center. I still have lots of little things to do before it is done but I'm a bit closer.

Below are a few pictures. As you can see I don't have an exhaust yet and the stocker won't fit without some serious mounting brackets and it would look weird. I have also acquired the Daytona Anima FLX190 motor which I will install after I prove that the 126cc motor won't blow up. I'll likely then sell the Honda motor unless I find another CT90 to toss it in. Once the 190 is installed I'll run it for a bit and then powdercoat the frame.

I'm not sure if I want to run a front fender or not... Thoughts?

IMG_20150205_161355.jpg

IMG_20150205_161347.jpg

IMG_20150205_161302.jpg

IMG_20150204_205354.jpg

IMG_20150204_205421.jpg
 
Enginedoctor

Enginedoctor

Well-Known Member
how did you get the 90cc platform out to 126cc's? are you running an atc125 crank?

personally i think you should run a front fender.i don't know how you're gonna mount it. stuff will get chucked everywhere once that tire heats up and sees the smallest amount of dirt.
 
W

WonderMuscle

Member
From the OP.

WonderMuscle said:
I have built a 126cc honda motor from an ATC125M crank, ATC110 cylinder and an ATC125M piston. I had to machine the crank to fit the CT90 cases and the dome of the piston so they wouldn't hit the valves. Finding a cam chain that was the correct length was the most difficult part. This motor is finished and sitting on my tool bench waiting to get put in the bike. This will happen next week, I hope... i will probably run this motor for a few months and once proven I'll likely put it up for sale. I will then buy a Daytona 190 Anima FLX and modify the frame to fit the motor.
Click to expand...
 
Enginedoctor

Enginedoctor

Well-Known Member
WonderMuscle said:
From the OP.
Click to expand...

ahh i missed that. put words between pictures and they might as well be invisible...:43:

i like your craftiness. i was always wondering what it would be like to stuff the 125 crank into 90 cases, AND if it would work. what portion of the crank did you have to machine to get it in the cases?

i read about a guy down under who modified his postie bike (ct90) out to like 150+ cc's, if i remember correctly, but if i'm not mistaken he used a powroll crank (pin location moved) and the 125 top end. there's so many ct90s out there, yet so few options for making them into the savage beasts they deserve to be. i bet it's nice having the additional 37cc's of displacement with the side car, or just in general really. The bike is really unique. nice work :41:
 
kirrbby

kirrbby

Well-Known Member
X2, and would you share the info for the cam chain, length? In case someone else were to attempt that engine build. Would be appreciated.
 
W

WonderMuscle

Member
It is honestly easier to modify the frame to fit a ct70 type motor. It only takes a few metal tabs and a welder.

To modify the crank you need to machine the generator side of the 125m crank to match the ct90 crank including the keyway. The cam chain is from a ct110, 88links. I tried a 90link chain it it was too long.

I bought the crank of eBay and just made it the same as the ct90 crank.
 
Enginedoctor

Enginedoctor

Well-Known Member
understood. in this case, with this bike, i'd prefer the 90 cases for the sub trans. i don't like welding anything onto any frame either. that's really just a preference that i'm partial to, but i'd prefer, if i needed to return the bike to stock, to swap a crank…. not that it's an easy task.

i'm glad the clutch side is the same.

if i had it my way, i'd like to do a ct90 w/ atc125 crank/top end, an sl90 clutch and cover, and keep the sub trans. that'd be a 4 speed manual w/ low range 125cc….. w/ 8mm cylinder studs and a stout bottom end.

i like where you went with this project. not many people tackle anything 90 platform. good work.
 
W

WonderMuscle

Member
Thanks for the comments. I've had a few ct70s, a grom, and a ton of dirt bikes and my ct90 is my favorite. It is very well balanced and slow, fun slow. I have more parts for my CT to get it 100% but work is killing me and I dont have time to button her up. I hope to have some time late Feb to give it a go.
 
W

WonderMuscle

Member
CT190 Anima

Well, I've got an update. I was able to work most of the weekend on motor install, wiring and some other minor bits. I hacked a few things together to get it up and running but will sort through them in the coming weeks. My list is still long though, see bottom of post.

The bike is Fast, it might be one of the more frightening creations of mine yet. It lifts the front end in 2nd and 3rd, I didn't even bother getting on it in first. The motor has some serious power for a mini. The seat is a bit odd and needs to be reshaped but I'm not sure how yet, I'll need to get more time on it to determine what it needs.

It sounds fantastic with the Over Racing pipe and looks sweet too. The front brake is great but the forks are a bit soft compared to the rock hard rear shocks. I had to grind down the rear sprocket to fit the 420 chain, was 428 sprocket. I have a new smaller rear sprocket set to arrive this week, I will send it out to anodize before I install it.

IMG_20150405_181940355.gif

IMG_20150405_181957170_HDR.gif

I unfortunately lost the rear taillight and license plate on one of my rides yesterday, so no ripping it around till I get that sorted out. I'll update you all in a few weeks with more progress.

I bought the motor and many other parts from TBolt USA. I'd like to give them a shout out, they have been very helpful with wiring info and other motor related questions. Thanks guys!


Petcock tab
Speedo - Trailtech Vapor set in OEM bucket
Seat reshape
Add vibration isolation
Braided front brake line
Front brake-line clamp
New grips - White was a good idea but not so much
Weld up frame tube
Fill holes in frame
Straighten rear fender
New connectors in headlight bucket
Longer Kickstand
Powder-Coat Frame
 
Last edited:
B

bruces

Active Member
I am just about to start building my ct90 ,and am interested in fabricating a side car for it .Do you have any pictures of how it's mounted and constructed ,and any idea who made it if it isn't homemade ?.Pretty sure my daughter will end up with this bike ,and I can see her buzzing around town with her dog in it .Also ,any idea how heavy it is ?
 
W

WonderMuscle

Member
bruces said:
I am just about to start building my ct90 ,and am interested in fabricating a side car for it .Do you have any pictures of how it's mounted and constructed ,and any idea who made it if it isn't homemade ?.Pretty sure my daughter will end up with this bike ,and I can see her buzzing around town with her dog in it .Also ,any idea how heavy it is ?
Click to expand...

I have not ridden the bike with the sidecar yet at my friend has been rebuilding it. He actually has some guy in Tustin do the structural and mounting work for him. I have not seen it yet. I have heard that it is very sketchy to drive. It is heavy and hard to control. I don't know that giving it to your daughter would be wise. I'm not sure "Buzzing" would be an appropriate term to describe a CT90 with an additional 120lbs strapped to it. I hope to head up to his house in the next few weeks and I'll see if I can get some pictures.
 
Top Bottom