Planet Minis

HaiSpeedZ50R

Is it possible to install the shift drum incorrectly and get the wrong shift pattern? I was wrenching my butt off all late last night and this afternoon in frustration only to find out the shift pattern on my supposed '85 ATC70 4-speed is all down. I was under the impression the 85' is all up. If I had known this I would've been finished yesterday instead of diagnosing a problem that never existed. This is why I hate buying from "bulk part out" sellers on ebay. Sometimes they label stuff wrong and it ends up giving people(like me) headaches and a looot of stress. This being my first case split/tranny job there's no way I would known it by just looking at it. So am I right to vent or did I install it wrong? Oh yeah, to top it off the used carb I bought has a pissing problem. There's no cracks in the float and the valve needle looks intact. What else can I look for?

SlowSeth

Shift drums can't be installed in a way that give you the "wrong" pattern. It takes a shift drum with opposite pattern.

In road-racing we swap shift drums all the time, to give the 1 up 5 down pattern (known as GP shift) so we can upshift while leaned into left hand corners.

As far as the carb goes: if the float height is too high, the needle is stuck, or the needle and seat are messed up. Make sure the overflow tube isn't loose in the bowl either, I've seen them come loose and leak.

HaiSpeedZ50R

Yeah..that's what I figured. I was just informed by a fellow PM member that the early 85's had a down pattern so I guess no one is to blame for my frustration except me. I was working on the bottom end till like 5am last night. Sometimes you just gotta take a break and think things through huh? Well the carb is still having a "bladder problem"..I took off the float bowl like 10 times already and I can't visibly see anything wrong with it. My guess would be the needle or the seat. I think I've lost about a gallon of gas testing this thing so far.

ducatilover

Could be a bad o-ring on the bowl's drain screw (I think that's what you call it). Where is it leaking from?

HaiSpeedZ50R

Everywhere. Overflow tube, intake outlet(when i'm testing it off the manifold).. It's coming out the air filter too. It just seems to fill very quickly then tries to find a way out of the carb.

50rider340

it is definitly something to do with the float needle. Try going over board and push up the center peace to see if you could get it to stop. Does your tank have a on and off valve? If it does. Take the carb off the motor if it isnt already. Take the bowl off but leave the floats on it. Then turn the fuel on very little So you dont have fuel pissing everywhere. Then see if by pushing the floats upward as they are supose to do if the fuel stops. If it doesnt then you know it is something wrong with the needle. If it does stop then you can trial and error everything else.

Heres a good link to go by Id go over kill with the float settings to see if you can get it to stop pissing out. If you cant then your prolly missing something in there.

http://ep.yimg.com/ca/I/dratv_2077_54522429

mexicanyella

They can act up from wear/damage that is very hard to see. You sure your float still floats? I've never had a sunk float on a bike, but I've had it happen on non-bike small engines a time or two.

HaiSpeedZ50R

It's probably the needle then. I tested it like 50rider said but used my finger to press the "nipple" of the needle and the gas still comes rushing down. Can someone explain how it shuts off the fuel when the needle is in use? The tip of it is just a pointed piece of rubber. I don't see how the nipple comes into play.

mexicanyella

The nipple's just a little spring-loaded doodad to make the shutting action of the needle/seat gentler and more gradual, I think. It is not really a valve or anything. You've got the leverage of the float arm multiplying the up-force, or bouyancy, of the float to force a very small sealing surface together, so a tiny float can hold back a gallon or so of gas with a foot or so of head above the carb. If that needle tip or seat is nicked or worn or deformed or crustified, it can't seal the flow.

HaiSpeedZ50R

Gotcha! thank youuuu

HaiSpeedZ50R

Welp..I think I fixed the problem. Turns out the guy(thanks Greg) before me didn't know what he was doing when it comes to carbs and put the breather tube on the fuel inlet. Since it came that way I only assumed the other inlet was for the fuel. You can imagine how much gas I've lost with this mishap. Coupled with me not knowing how the float/needle work I didn't pick it up right away but hey, better late then never.

mexicanyella

Well, there's one to add to the troubleshooting memory banks. Never heard of that one before. So canya ride the thing now?

HaiSpeedZ50R

Yah mon..finally get to enjoy this thing. It's been apart for about 3 months in pieces waiting for the funds to come in. Minis is definitely not a poor man's hobby.

mexicanyella

Are there photos?

HaiSpeedZ50R

oh it's just a stock looking 1999 Z50R. I have some pics of it when I first got it. It had good compression but smoked like a chimney.



Right now it's got a crf70 top end, atc70 4 speed, low hour crf50 crank(old one had some up and down play), new DID cam chain, and a cut stock stator cover. I also have a new Takegawa econo clutch kit and a new Dratv 88cc bbk but I'm gonna hold off on that for now. I kinda like the auto clutch and not having to wheelie all the time in 1st. Future plans are: xr75 swingarm, Red or Chrome Kitaco 265mm shocks, Snow hawg tires, and maybe a klx 110 forks if it isn't too complicated. That's it for the "dirt" bike. I wanna buy a monkey for the street but don't have any money for it right now

mexicanyella

Sounds like a good all-around combination to me. Nice-looking bike.