Planet Minis

1993z50r

can you tell me if its a points engine, and what mods i can do to it, how hard it it to tune. and help is appreciated. can i can use common parts like cylinders, heads, and internals.

Z50King

he wants to know if he can use common parts like cylinders, heads, and internals

guardian327

^^^hahaha, yeah...

why did you buy a '76 engine? and of couse it has points... its an 76.

turboglenn

well, as you now know it is points. most of the aftermarket things you can get for a modern CRF motor can be had for the older 81 and older short rod motors. since the head is different things like the cam and piston need to be made to fit it particularly. TUning is in the carb adn exhaust system changes so it tunes like any other fifty motor. the timing isn't too hard to set and that's about the main thing that's different.

that should cover what i can tell you..the rest you just have to read through the forums, use the search bar and you'll get pages of stuff to read through..

remember 81 and older have a shorter rod than the newer styles,This makes the piston have the wrist pin in a different spot, so th episton needs to be specifid to your motor ( as well as the head having a bigger combustion chamber so teh piston needs a higher dome) The cam is also different by the type of bearings on the ends. YOu might want to search by "short rod motor" or somehtin like that.. you can also look through parts vendors pages and read carefully and you'l come to learn what fits what just from that

fastbmw

I've got a brand new 72cc piston with rings for the short rod engine like the 76 for sale. PM if you're interested. i'll sell it cheap.

arlindsay1992

I got a lightly used 88cc bore kit for stock head that will fit that motor. About 2 hours on trails on the parts. I'll include all the top end gaskets except for the head gasket. All new. Let me know.

Thumpin90

arlindsay do you have any friends?

arlindsay1992

Funny, and yeah.

tmas

I remember the video on qwokes friend Amir, the dude who crashed his bicycle while riding it backwards into your brand new tank.... ouch.
Qwoke, is he still your friend?
tmas

vigcs

Less than that!! Maybe an hour of riding time on it, haha.

arlindsay1992

I rode it a bit after I bought it from you. Biggest motor I've ever ridden! And yeah me and Amer are still great friends. He rocks the MTB but he's got a much better bike than in that video. Yeah. Me and Amer are cool.

turboglenn

dude...what's up with all that carbon and build-up and oil on that thing... looks more like 2 years of use .. I"m not calling you a liar so don't take offense, maybe it was the condition of the rest of the motor that dirtied it all up. I was just looking at a top end i have with about 10 hours on it and you must have had insanely bad valve seals or something to accumulate that kind of build up in 2 hours of trail riding

here's a 10 hour top end..wiped dry with a paper towel, but other than that not cleaned up at all.

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arlindsay1992

I am not worth much when it comes to tuning carbs. But I'm sure it was not the valves. I replaced the seals and lapped the valves. So I think it's all in the carburetor. It used the stock carburetor and stock jets. And some of the oil is there because I dripped some into the cylinder and smeared it around to keep it from rusting when I put it in storage.

turboglenn

that makes sence.... you must have been running rich as hell

like i said i wasn't trying ot bust your chops or anything i was jsut amazed how dirty it was for only 2 hours use... but having a carb way out of tune on the rich side is WAY better than having it way out on th elean side... at least carbon cleans right off.. so that kit is for an old style big dome head? I actually know some one that might want it for his old Z