1986 Honda Elite CH80

[joeorange]

i am making this thread to just share some of the things i have had to do to my fathers honda elite 80.

when we first got it it looked like this.






    we picked it up for $50, with title. it needed engine work, mainly a new piston since the old one seized in the cylinder.  so i looked up some info about the stock piston for the CH80, and found it took a 49.5mm piston with 13mm piston pin. and i found out that the 50mm 139qmb big bore piston had the same measurements.

    so i purchased a 50mm high compression piston and had a machinist friend do the work on the cylinder to accept the new piston.
i also had to purchase a full gasket set. while i was waiting for the cylinder to be done i purchased a 19mm cvk carb from ebay for the 139qmb and modified the stock intake so i could just use a piece of hose to attach the carb to the engine. i have already done that, but i have yet to make a vacuum port protrusion for the vacuum operated fuel petcock. that will be later.

    after the cylinder was done i got to work and put the engine all back together, and found some pleasent results from using the 50mm piston. for once when the crank is at TDC, the piston crown is flush with the top of the cylinder, which is much better then the 0.6mm gap that the stock piston is supposed to have, which will help increase compression. which with these engines is a big help with power.

    before i assembled the top of the engine i decided to strip the head and do some light port work just to help flow with the new 19mm carb. after that i cleaned the head, seated the valves and reassembled the head and then put the engine all back together.

    like the 139qmb and 157qmj engines the ch80 engine was easy to set the timing. once everything on the engine was put back together i installed the engine into the frame a began hooking the wiring, brakes, wheel and exhaust.





this is all i will be posting at the moment until later when i have taken some more pictures and made more progress with the elite 80.

[joeorange]

Made more progress today with getting the vacuum port made for the intake manifold. what i did was drill a hole a little smaller then the barb, then heated up the manifold and hammered the barb in. i then let it cool, so now the barb wont be coming out anytime soon.



after that i put all the bare eccentails on it and wheeled it outside.





you can see how i have the carb hooked up in these pictures.







i then put some fuel in the tank, and oil in the engine and started it. it fired right up once i primed the carb and fuel lines. i then let set the idle and idle air so it would be rich since the air filter i ordered for it has not come in yet. once it was warmed up i let it idle for about 5 mins to help the rings break in. at first there was tons of smoke coming from the exhaust since there was still the break in oil in the cylinder and some oil in the exhaust where the rings failed before the rebuild.

now the part you've been waiting for, a video of it running.


there is yet still more to do, like the custom exhaust, some cvt work, and a new cdi and ignition coil upgrade. but the main thing for now is that after 4 years the 1986 Honda Elite CH80 is running.

[lordverminaard]

Very nice. Love these old Elites. They come up on our local Craigslist frequently, good to know you can hack QMB parts on them.

Good work!

Brendan

[joeorange]

well, i took the ch80 out for a little drive around the parking lot. it was driving good, had good power and torque, got up to speed real quick. and performed really well. as i was coming back to the house it died on me. so i tried starting it up and nothing. so i looked down at the carb and it had feel off the intake manifold. the hose i was using didnt have enough of a grip on the manifold to hold the carb, so im going to have to get a better coupler to use and maybe make a support bracket for the carb so it doesnt fall off.

['O'Verse]

Is that a 4stroke carb your using?

[joeorange]

Sept 26, 2017 13:34:04 GMT -5 'O'Verse said:

Is that a 4stroke carb your using?

yes it is, because it is a 4 stroke engine. now a 82cc vertical 4 stroke engine.

['O'Verse]

Sept 26, 2017 17:09:18 GMT -5 joeorange said:

Sept 26, 2017 13:34:04 GMT -5 'O'Verse said:

Is that a 4stroke carb your using?

yes it is, because it is a 4 stroke engine. now a 82cc vertical 4 stroke engine.

Nice... I thought you might have gotten a 4 stroke carb to work on a 2 stroke there for a second. I heard It was possible. Just haven't seen it yet. 

[joeorange]

Got the intake manifold coupler issue fixed. The hose that I was using was too weak and thin so I bought a thicker one and some.new clamps and it won't be going anywheres anytime soon. Also put on a spare air filter that was lying around to keep the dirt and grit out of the carb.

But now I've run into another problem with the build. But it's to be expected with 31 year old parts. The engine lost spark. So I'll be ordering a new coil and cdi for a 139qmb and upgrading the ignition system.

[joeorange]

well, found out that the cdi has died on the elite 80, its to be expected with a 31 year old part, and i was planning upgrading it anyways, so ill be ordering a performance cdi and ignition coil set here on payday. then that leaves me with the exhaust and the cvt tuning.

[joeorange]

Decided to update this thread.

The main updates are as following.
A Brand new stator has been installed, brand new cdi, brand new coil, new slider weights in variator, new 1500rpm torque spring, 1000 rpm clutch springs, a new custom build intake manifold and custom throttle cable, new custom wiring harness and a new battery.

after all those parts it now runs almost perfect. the last thing that needs done to the scooter is a new custom exhaust that will allow the engine to flow and perform better. the stock exhaust is super quiet, infact too quiet for my taste, that and the exhaust pipe inside diameter is only 1/2" while the exhaust port is closer to 3/4", i want to match the exhaust pipe size with the exhaust port so i can maximize the performance of this engine. once i get the engine running and performing perfect, there is still the matter of the very undersized variator.

sure the stock variator works just fine, but its very limiting. so limiting that the torque driver is being used to it max potential. if the variator drive face was just a bit larger the belt could travel to the most furthest depts of the torque driver, and climb the highest part of the variator so you could get alot more speed out of it.

but so far my attempts at finding a suitable replacement variator isnt turning out so well. but i wont give up, even if i have to make a custom variator boss bushing so i can use some other variator and drive face i will.

i want to get the most out of this 32 year old beast.

[joeorange]

well, got another update for this thread.

finally got around to making a new header pipe and exhaust for my fathers ch80.





i ended up making it out of 1" stainless steel pipe from an old shower grab bar, and i reused the stock manifold flange.

heres a comparison between the new header and the old.






as you can see, the stock exhaust was tiny, with a ID of 1/2". And with the new header it flows real good now.

i also bought a briggs can muffler and welded it to the header and added a exhaust tip to the muffler to direct the exhaust away from the wheel. i forgot to take pictures of the end product, but it performs awesome now.
i will have to get another can muffler to add inline to the other one since its a bit too loud for my father.

but the old little red rocket now moves, and in a hurry at that. from stand still to WOT it pulls hard and strong. i do not know what the top speed of it is yet since it is not licensed, but it is all ready for when it is.

i will be posting pictures of the complete finished exhaust when i have it completely done and reworked.