lifespan of engines


New Member
May 11, 2008
Santa Cruiz, CA
Nearly finished with my first kit, an 80cc one that has a rather low quality feel to everything, so I'm worried about the lifespan of it. I was hoping to communte to work for 5 months of nice weather. 20 miles one way, 200 miles a week. Can this really last for almost 5000 miles? Assuming synthetic oil at proper ratio (16:1 break-in, 20:1 afterwards).

Is there something typical that goes out first, second, etc?

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
up north now
Yes, they can last quite awhile if taken care of properly.

I'd mix the fuel at 24:1 after break in unless you want to do a lot of plug changing and de-carboning.

Common wear items include rings (cheap, easy) chain/sprocket, also cheap and easy and maybe after 5-6000 miles a wrist pin bushing or bearing, depending on your engine. No biggie.


Master Bike Builder & Forum Sponsor
Dec 28, 2007
Duvall, WA PNW
Oh you should get more 5000 miles, If you take decent care of it. They are rough, but in some ways that means they will keep on going. Respond to the odd noise, change the plug, watch your chain or bag the nasty chain altogether.

Yes a good synthetic oil will help…..but even 20:1 seems really strong. You could go 30:1 easy with something like Saber.


Mar 8, 2008
I typically rering an engine every 12 months of use. It is cheap and easy. If a bushing bearing looks like it is wearing, it gets replaced. So far never had a bushing bearing wearout cuz I use Maxima 927oil which has 20%castoroil in it.

Jemma Hawtrey

New Member
Dec 29, 2007
Essex, UK
Its the same with everything - take care of it and it will (generally) take care of you.

Personally I would swear by the GEBE kits because they are fit and forget - mostly. The problem with them is where they mount and also that you are stuck with a single ratio - there is no way of putting the output through a gearbox.

I have done probably over 450 miles on mine and all I have done is checks and put fuel in it when it needs it. I check the spark plug very rarely and the thing on my bike that has needed most attention is the front suspension..

I think for the distances you are talking about decent suspension and brakes are a must - lights as well if you are going to be riding darkside :)

Its actually beginning to be a bug bear with me the number of people who dont ride with lights - not even LED's - and expect motorists to see them... you can guess who will get the blame.. and its not the person on the bike..

Jemma xx


New Member
May 11, 2008
Santa Cruiz, CA
YAY!!! Took maiden voyage last night! Vibration transfer up to handlebar and seatpost may get tiring. 80cc 44t too slow on the flats, barely goes uphill unless pedaling.

The bike I'm using is my baby. Personally handbuilt high-end mountain bike with very stout components wheels, and suspension. I used to night ride a lot, so already had dual 12w lamps, one spot, one flood. Will get another flashing red taillight, as well as those reflectorized velcro bands for my pantlegs, to keep them from hanging up, as well as provide a visual wobbling notice for cars from the side as well as rear.