Changing from long to short shaft? By jofos (Read 1,286 times)

[jofos]

(Originally posted in "GY6 50cc Engine Noise Problem (Again)" Moved to new thread in case anyone else needed to know how to change a shaft.)

Well, in case there is interest, my engine finally blew out. Was coming home from work and it was rattling and humming and BOOM! Shakalaka. Dead.

Fortunately I had already ordered a new engine, unfortunately it won't be here 'til Tuesday. Also I am not so sure it will fit easily. Scrappy said "the new engine may have the long-shaft for the dual rear shock bikes" and later: "Yeah, sorry. I was right, all of them are long shafted."

So. I am getting the shaft! (hehe) No, he said that I could switch out the shafts, but I really have no idea what he is talking about. He said this: "It's not a big deal, it just means taking the rear transmission off both engines and swapping out the shafts..."

Could someone please give me a little more info? I am hoping to get most of the removal and setup done so I can get the new engine in as quickly as possible and be able to get myself to work!

Thanks...

[sprocket]

Best to get a generic manual from the internet. You will need a bearing puller and probably a replacement final drive shaft seal.

you need to open the CVT
remove the complete clutch assembly
drain the gear oil and remove the transmission cover plate (3 bolts)
remove the transmission cover
remove the gasket and locating pin...
pull the final drive shaft and replace it with the old one...

You need to torque the transmission cover plate to 8-10 ft/lbs on reassembly...

Fill with gear oil

[jofos]

geez. Don't sound fun at all... Thanks for the info! I think I will wait til the whole thing gets here to sort it out. That is a bummer... Wish I would have thought first before buying, but it just seemed to indicate, on the website by the pic and description, that it would fit with no problems.

Disappointing to say the least.

[robb]

Could you just tac on a new shock mount on the frame?

[jofos]

well. Got the engine, and started working on it... Removed the old engine, exhaust, carb/filter, rear wheel, and disconnected anything still attached. Paid attention to the wires, on the new one there were only two main wires, one assembly and one hot, and I made note of where they went. I then took out the short rod that the rear wheel mounts on to. (As posted above, did all that.)

Bolted on the new one, changed out the intake because the new one was missing a vacuum that I believe my fuel system needs, installed the carb/filter, hooked up the wires, did a valve adjustment, and then took apart the black area where the kickstand is (cvt?). Took off the clutch assembly, removed all the bolts to get the transmission off, and took it off. Removed the rod, replaced with the new one, and reassembled. Lost very small amount of gear oil, so added a little. Checked oil, added some oil. Put on rear tire, and then exhaust...

Tried to start it, no starter at all, and the battery seemed weak. So. Kick started. There was a weird kickback from the starter arm every so often. Never happened to me before. After a few tries it did start, but just a few huffs and puffs. It would start to make a screeching noise, like a starter grinding on the teeth... and cut off. Tried a couple more times and it started again and then the kick starter arm suddenly swung up counterclockwise, from about 3 o'clock to 11:30.

Took off the cover and the little bit of metal that restricts the counterclockwise movement of the kick starter assy was broken off, and the metal wheel on the outside of the front part that holds the belt was a bit (very small bit) wobbly... Reassembled, after taking off belt and putting it back on, and making sure the part wasn't wobbling any more and tried again. The kick starter wouldn't move.

So I took the old cover and put it on. Tried to kick it again and it made the same kinda noise. So I gave up, not wanting to cause any (more) damage.

Worked on it for 5 hours, after working all day, and nothing. I am VERY disappointed with scrappy dog due to their lack of a complete description and then shipping the damn thing while we were in the midst of discussing whether or not it would fit... "Oh it'll be fine! No Problem!" BS

I really think I could have had the thing up and running if they had sent me the correct engine assy. (I do realize I am partially to blame for not checking further, but if you look at the site and description it looks like it will work fine.)

So. Sorry for the rant, but I wanted to have all the details...

Any advice on my problem?

[iceman]

Where's this noise coming from? I wonder if your starter bendix is missing the bushing---to keep it from wobbling? Take your cover back off and see. Maybe that's the sound you hear??

Also, with the cover off, when you turn the variator(front pulley) by hand, do you hear that sound still?

I'd also check the valves to make sure they are set properly. Got oil in it?(just saying... )

[jofos]

hey thanks for the replies! Unfortunately the starter wasn't working at all, as I mentioned, so scrapping the kick starter wasn't an option... And I don't have an air box (uni-filter). It was getting gas, as it did crank a bit and run for a second or two. I was just trying to get it started and worry about the starter later.

I will check the things as advised after work today, and try to get the starter working... Thanks again and wish me luck!

[iceman]

Apr 13, 2011 4:16:40 GMT -6 jofos said:

hey thanks for the replies! Unfortunately the starter wasn't working at all, as I mentioned, so scrapping the kick starter wasn't an option... And I don't have an air box (uni-filter). It was getting gas, as it did crank a bit and run for a second or two. I was just trying to get it started and worry about the starter later.

I will check the things as advised after work today, and try to get the starter working... Thanks again and wish me luck!

Good luck buddy!

[jofos]

Well, I got it started... Took out the starter gear from the cvt, and kick started it. It will start and idle, very roughly, but will not take any gas at all without sputtering out and sending a waft of smoke out through the carb... The spark plug came out all blackened when I changed it to see if that would help. Tried adjusting the vales to .002, .004, and .006. Drilled holes in the exhaust. I am at a loss! (Adjusting the valves out seemed to improve the tempo a bit as I increased the distances, as did adjusting the idle. I could get it to idle relatively smoothly, but nothing else!) HELP! (please...)

(BTW I bought a gy6 80 engine assembly and put it on a stock 50. Main jet was upgraded, and I put on a uni filter. Upgraded the cdi. Has a new ignition coil and spark plug)

[iceman]

Blue or black smoke, I'm guessing blackish?

Hmmm. What size main jet do you have in there---the 88 range approximately?

Have you tried taking the intake manifold off, and checking the condition of the little spacer in/underneath there, and even the o-ring? Is that the piece (intake manifold) that you changed out-- when you stated that you "changed the intake, because the new one didn't have the vaccuum that your scoot needs"??

[jofos]

I have started a new thread to try and get help with my new problem... Thanks!