Thread: Cost to Rebuild Honda Motor More Than New Lifan

Will Lifan 90cc fit in a Z50 Frame?

Why do I ask?

I made the mistake of having my friend the retired motorcycle/jet engine mechanic look at the stock Honda motor in a '78 Z50 I found. After I went through the trouble of breathing life into it by adjusting points/valves/carb, etc - he tells me it is a miracle it started at all.

We tore apart the top end (in about 9 minutes) and found bent and tuliped valves, a cylinder and piston that hed been seized at one time and pitted both. Our estimates for parts and machine work outweigh the cost of a new Lifan. Thing is, all I can get ahold of right now is a 90cc semi auto.

Will this fit in a Z50 frame?

Thanks for any help,
-Todd

The 90cc motor in question should fit your frame. If it looks like your stock motor, then it's based on the same Honda 49cc lower end design.

As for comparing the initial price to get your existing motor like new vs new made-in-PRC repop motor, does the terms "apples-to-oranges" ring any bells? It's a broad topic with many different perspectives/opinions. IMO, the 90cc motor might be the better starting point. Honda quality it isn't, but then 49cc won't make anywhere near the power - a consideration if you intend to ever ride on the road. From there, things get complicated in a hurry. Suggest you read through some of the long threads covering the Honda/Chinese motor discussion.

If you go the Lifan route you'll need to make the switch from the points type ignition to CDI, . . . which isn't necessarily a bad thing, but it does entail swapping out the wiring harness. If you have lights upgrading them and your battery to 12v will also be part of the equation.

-kevin

DrATV has a refresh kit for small Honda motors that gives you a new head, piston and rings for 109.00 Dollars. Throw on a new cylinder and gaskets and you could have it all back fresh for less than 200 bucks. My .02 worth
Good Luck

Originally Posted by bjatwood

DrATV has a refresh kit for small Honda motors that gives you a new head, piston and rings for 109.00 Dollars. Throw on a new cylinder and gaskets and you could have it all back fresh for less than 200 bucks. My .02 worth
Good Luck

True, and definitely an option but I would still need all of the timing gears, rollers, etc. Also there is my old gearbox that we never even adressed. We just put the head parts in a box and figured why bother even looking at the tranny. We could see after pulling the right side cover that the screw that holds the shift drum stopper had backed out and was almost rubbing on the main gear. If that is indicitive of what lies underneath the main gear, then my gearbox has other issues. The Lifan looks like the best way more and more all the time.

I will say that I have a clone CT70 and have put a couple hundered mountain miles on it without incident. It is a perfect little machine.

I have done some reading here but I find the forums are too general for sucsessful searches on a given topic. The only negative things I have read is carbs and intakes not fitting beneath gas tanks. What am I missing about these Chinese motors that is so terrible?

-Todd

What I would do if I was you is go ahead and get the Lifan motor and go ride. BUT keep the honda engine and at some point either make it a project and rebuild or at least have it available so if you intend to sell it, the next guy like me, could put it back to original.

Originally Posted by XSIVE

........ or at least have it available so if you intend to sell it, the next guy like me, could put it back to original.

I'm a gear head, not a purist

This project is going to be a super clean, Nano Thumper. I wish it could be all Honda but it looks like that is just not in the cards for this little basket case.

Like you suggested, the original motor will be redone at some point. My expendible income is not as liquid these days.......

-Todd

My expendible income is not as liquid these days.......

Not sure if any Red blooded American income is as liquid these last few days of Uncle George's regime.

I'm in luck!

This just appeared last night and it's in my town!

Pit bike parts

Does anyone know if this lower end is the same size as a 50?

-Todd

I bought it. I'm happy. Super nice engine. The purists wont be happy because it is far from original but at least it is not Chinese.

-Todd