125m conversion on '79 atc110... help!

[jchx99]

Hello everyone,

I want to buy a 125m engine and whatever necessary parts I'd need to make it all work on my 79 atc 110. I have already realized I will have to figure out something for the headlight and taillight, since it will be 12 volt instead of 6. Also, for the electric start to work I'll have to fabricate a place to put a battery. I was wondering, though, will my ignition coil work on the 125m engine? Does the CDI ignition require a different ignition coil, or will my current one be fine? I have summed up the parts I'll need... please tell me if theres anything unneccessary or missing...

-125m Engine
-Electric starter for engine
-Intake manifold for 125m
-125m wiring harness
-Keyed Ignition switch
-Light switch/Kill Switch for 125m
-125m CDI box
-125m starter solenoid
-125m rectifier regulator


... and a battery.. do I need that hooked up for the engine to run, or just for the electric start? Do the lights run off the battery? Also, is the exhaust port in the same spot, so my current exhaust will mount right up?

Other than that, is there any other things I'll need or anything I should know? The motor should mount up fine, it's the same design. The only thing I could think of that I would need, other than the things I've listed, would be an Ignition coil if my current one won't work. Once again, my bike is a '79 110 (6 volt)...

Thanks alot,

Jordan Hinze

[greenhuman]

Go to Ebay and buy a complete engine. Sometimes the seller will throw in the complete 125m harness or sell it cheap. That way you will get everything you need in one hit. The pipe is in the right spot. The 125m uses a smaller flange and bracket so a slight mod will have to be done there, nothing too dramatic. Try to get the carb and manifold as well. The battery will fit in the 110 back bar. You will have to make a battery box and MIG it into the bar at the rear of the tail light.

[danteross77]

Not sure why you would want to do such a conversion, I think it would be more cost effective just to upgrade your 110 maybe a big bore kit or such. The 1979 coil will not work on a cdi ignition. All the parts you will need to buy and fabricate for battery wouldn't it be easier to find a used 125m in need of a rebuild? I beleive the 125m had a longer wheelbase also. If you don't like the points ignition you can alway upgrade to a 1981 or newer 110 with a cdi, thats what I did. And on electric starter, they are nice, but not to sound sarcastic but if you have everything lined out one easy pull is all you need and she is purring like a kitten. I just don't think you are going to see that much of a change in performace to justify spending that kind of money. I think it would be easier and more cost effective just finding a 125 and selling or parting you 110. If you want to fly I would recommend buying a larger trike, but Honestly my 110 has no upgrades at all and I actually enjoy riding it almost as much as my 250sx. Its just a light fun machine to fool around on.

[jchx99]

hello again,

What do you mean by the 'flange and bracket' are smaller? Do you mean on the exhaust? Or the front motor mount thing... if so I can get the 125m one. If it's the exhaust, I have a DG pipe on now that looks like it will work fine. Other than that, seems like it will work out OK.

two questions though:

What are the essential things I need to run this engine just with pull start, and what are the essentials to use the electric start? ... and does a battery have to be hooked up for the lights to work, or the engine to run?

Thanks again,

Jordan Hinze

[Vealmonkey]

Instead of going to all the trouble of the 125, why don't you just see about getting a better cam, a larger carb and maybe a larger piston. An improved airfilter would help too. Also, you can probably change the rear sprocket 1 or 2 teeth lower for some more speed. Look for an aftermarket frame to replace the stock frame. They are usually lighter and 2 inches or so longer. Less weight, more speed. Tire changes like to a smaller size can help you get a little more speed but it can roughen the ride up a little bit. A 125 swap seems like an awful lot of work.If you could shave a little off the head or get a different piston, you could bump up the compression ratio just a tad and get a little more power that way too.