Lifan engine upgrade on Honda CT70

Search engine locks up when I try to do a topic search.
I see that the Lifan company offers engines to upgrade the Honda Trail 70 ( CT70). Has anyone here done this and which engine would you recommend?
I bought the bike with a damaged gear box for almost nothing and was thinking it might be fun to up-engine the little bike.
I'm not trying to restore the bike to like new,just want another bike to climb the mountains.
Dr. ATV has the engines and, I believe, a wiring harness conversion kit. There are companies selling CT70 repros and they typically use the 125cc engine, not sure you can go much higher on the little CT70, but there are other vendors who sell larger engines (140cc and 150cc engines).

You can use just about any chinese clone engine you can find. i had a 50cc mini chopper that was a 4 speed semi auto and was a great bike. 110 dirt bike would make a good donor and can be found pretty cheap, sometimes a lot cheaper than a brand new lifan. can find them in semi auto and manual clutch :thumbsup:
The more I research this,the more fun it sounds. A co-worker here owns a powder coating shop, which would work well for bringing the bike up too 2014 for new paint.
The rest I can do no prob.
Thanks for the info so far,I do appreciate it.
clone engines in Honda bikes

The Lifan 125 in the CT70 is a blast. The Lifan brand is a very high quality mill. There are junky, low caliber engines out there... I'd only buy a Lifan.

I have a clone-powered 1974 Honda CT90 (Trail 90), probably one of the oldest conversions out there, completed in 2002. My brother installed the engine and got hung up on the wiring, which is where I came in. There were no wiring diagrams for the clone engines, and no wire colors matched anything.

The resulting wiring diagrams I drew were ended up making me one of the go-to guys on the internet for sorting out electrics on engine swaps. I joined the honda_clone site many years ago, and have drawn quite a few engine swap diagrams, such as the CT70 upgraded to clone power, CDI and 12 Volts. The CT70 is easier to convert electrically since it came with AC magneto ignition. Make it all 12 Volts and enjoy the ride.

The extra power is great, the engines are reliable, and for the non-purist the price tag is hard to beat. Since I prefer a manual clutch, getting a 4 speed on a CT90 has been a great upgrade. Having bright, 12 Volt lights and blinkers is worth every cent. The ease of starting created by CDI is maybe the best part.

Many folks install auto-clutch engines, and are very happy with those. The Lifan 110 with auto clutch is perfect for kids and lighter weight adults.

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Thank you for the wiring info.That will be very handy when I change the engine over. My bikes serial numbers shows it was made in 1969. The wiring that is there has been played with by it past owners. I have my work cut out for me.
I need to find out if I should leave it 6 volt or change to 12 volt.
actually I wouldnt buy lifans
unless they offer different shift patterns

here is why

ive had 2 lifan 125 slip out of gear, badly
now im no master mechanic I dont dig inside the engine to see what to fix
some have said you can modify something to maybe fix it, who knows
but from what ive read the shift pattern 1,n,2,3,4 has a better chance of slipping out of gear

on my 2 engines it would be a slow down shift from 3rd to 2nd I give it gas and it slips into neurtal
Not fun on the street

Had this on one ct70, and one little dirt bike
on the dirt you have more time to recover
but if your trying to keep up with cars or whatever and it slips out of gear, it could cause problems

Plus the lifans I had, you had to be in neutral and dont touch the clutch to kickstart
alot of the time its really hard to find neutral rolling to a stop
and if you stupidly stall it, your stumbling trying to get into neutral, just to kick start it
which is always fun

Now I have on my ct70 a piranha 140cc
super nice engine I think its still china made but maybe assembled in the USA
not sure
what I did notice is paint marks over all the bolts which tells me they have been torqued and marked

Also it can start in any gear, clutch in or out
and shift pattern is n, 1,2,3,4 so its super easy to get neutral

Ive also installed a lifan 150cc
Cant remember the shift pattern on that one, wasnt my bike
it seemed built rougher, actually slower then my 140 by 5mph
same gearing too

anyways ever since the gear slipping I just look for n,1,2,3,4 shift patterns

BTW my 140 allows 35 miles on the little tank, thats all
I bought a side mount sub tank which gets me another 15 miles

Never checked when I had the 125 but it seemed I could go all day
so my only regret with the 140 is the mileage
power wise its fine, but I thought the 125 was fine too

never rode a stock engine ct70 but I have an all stock c70 but of course it has much larger wheels
it goes pretty well

Thank you guys for the info. It does seem that the Ifan engine has a problem with the shifter fork nut not having the locking tab washer which allows it to back out and cause just what you described. An easy fix,but it should not be there in the first place.
The newer engines are now UP shift pattern and have much better reviews.
I looked at the Piranha engine as well. I would have to remove a couple of cooling fins which is no big deal.
I like the idea of the oil cooler if for no other reason as it adds more oil to the small crank case.
With your engine putting out eleven HP I bet it is a lot of fun to ride!
I'm going to break out the pressure washer this morning and blast away the 45 years of crud off of the bike to see just what I'm up against.
I'll have it painted but have no plans on making it a show bike,I want to ride it off road in my mountains! Wahoo.
why would you need to remove some cooling fins? I didnt on mine and its on my ct70

also you need a cooler
My lifan oil temps would get around 225 I think which was good but still a little warm

the piranha got around 240 and I think from a chart I read 250 and higher really reduces the oil life
with the cooler im around 210 or less
A topic on youtube showed the guy had to remove two fins to get it to fit in his Honda.
the lifan 150, the 125, and the piranha I do not remember removing any fins to mount the engine
but who knows it was 2 years ago when I was doing those swaps

but even if you had to, its not hard to break off fins

I would be more concerned about which exhaust to use
I recently put a stock type on mine as I grew tired of the loud on on it
and had to reweld the rear exhaust mounting tab as of course the engine is longer then stock
which means the mounts wont line up
Rob go with the piranha. 140 with the 26 mm mikuni upgrade . I have one and they make great power and start first kick every time .
Next conversion I will try one of these, thanks David. While I have had success with Lifan, its good to hear a recommendation from someone who owns a decent mill. I have a C70 Cub in mind for a road racer build.

Buy a piranha 140cc from tboltusa they are great motors and they last for ever I ran them all the time still have mine from 4 years ago and it still runs perfect