Clutch Plate Falling OFF! Threads look Mismatched.

[stinky]

Hello,
I got my clutch cable on and set it. I noticed there was no feeling
of engagement in the clutch lever on engine. And the clutch was locked even though the lever was in and set to freewheel.

I opened up the cover and loosened the Flower nut. I was getting it where
it seemed perfect. Lever in freewheel, out it grabbed. I was playin with
it rolling back and forth, I had the set screw in. and the whole damn
clutch friction plate fell off!!! It is your standard 66cc chinagirl motor. 2011 issue.

I looked at the threads on the shaft and they were very small. they almost look like a variable twist. Fine at the start and then coarser farther in. Perhaps the machinist varied his hand cranked cutting speed?

The flower nut threads looked totally mashed and worn. The threads look far larger than the shaft threads.

So now what? Fabricate a new flower nut out of proper threaded nut?

Anyone else have this problem??

I did notice that the threads did seem to catch when I screwed the flower nut in without the plate on, but I am unsure if I can compress it that far with it on. I will go try pushing on harder with a 19mm wrench to see if it will catch, while I wait for answers etc....

 

[stinky]

I pulled the clutch lever in, letting the screw come out a little more.

I put on the flower nut, it got semi tight, but at a certain point did
not seem to tighten anymore. Tapped the outer plate 3 times, and the
cover and spring came flying off!!!

Not confidence inspiring......

 

[crassius]

you might save what's left of the threads with a new flower nut

 

[maniac57]

Replacement seems like the best option. You will never get a stripped nut to hold in this application.

 

[stinky]

Ok fine, I have kinda familiarized myself with the uninstall process, trouble is what part do I need?

Here is the exploded view of the Clutch Assembly,
http://www.pistonbikes.com/category-s/7.htm

I am guessing I need part number 18, the mandrel?? It looks like that part is
pinned inside the Main Drive Shaft. Everything else is new. I will need a new
Butterfly Nut as well, as threads are shot to ****.

Also I have to remove 10, the nut. And on other side 10 and 23?
I just want to know what I need to remove before I start hammering
the crap out of it!!

It's kind of confusing, a lot of the posts are about pulling the smaller drive
wheel. I read Normans post, but the process description is vague.

Any definitive instructions??

Gonna need a puller too.....

 

[stinky]

Look at the weird threads!!! Nowhere's near close to standard sized pitch on bolt. Not even close to the Flower nut threads, which are 6 -1.0(i think) threads.



Someone in the know just reaffirm the parts i need before I order them, would be much appreciated.

Read further into Normans posts and I see mostly how to do it. Best part is I will re-grease the
inner bearings with some top quality PTFE lube. Not the brown Hog Grease Drippings that were on
there!!!

 

[crassius]

I think that I would first try just a flower nut, and maybe tighten the inner spring to expose more rod and maybe file off a bit of the end of the rod to get to a better part of the threads.

Failing that, I'd just get a used shaft as a whole unit.

I salvage a lot of parts out of dead engines, but rarely even bother to save the shafts as they almost never go bad, so I just toss them rather than store a crapload of them. Someone near you may have a lot of them.

 

[stinky]

I actually did try that. It reaches a point where it does not thread any further.
Then with two taps on clutch plate...they dont have a animation of a bike falling apart, but put that image here, the Clutch plate flys off!!

The threads are grossly mismatched. I cannot see them ever holding under use.

Engine is brand new, so I just want to replace what I need on the unit.
Not really interested in putting someones beat on part into my bike.

The grease on the gears looked sooo sub par. What is on the inner ones??

And another point is, bearings quality. I am sure they are using the worse quality bearing. I may even go get a good Class Abec 3 bearing with ABMA 10 quality
ball bearings. Better made tolerances. Just don't slap anything in there.

Anyone know the bearing size as well? I go look.... ok say itsa a 6202, tons of them on Ebay.

like this one....http://www.ebay.com/itm/6202-ZZ-Pre...=BI_Heavy_Equipment_Parts&hash=item5af34e5ab3

and its local, they get here in no time!

Oh wait here is for 2 of them...which I think you need http://www.ebay.com/itm/2-6202-ZZ-P...=BI_Heavy_Equipment_Parts&hash=item5ae9d75dac

Or only one of them....lol dammit someone who knows this crap just type in you need x quan of these, x quan of these and for hub bearing x quant of these!!!! C'mon you fence sitters!!!

 

[stinky]

Ok after looking I found this!!

http://motorbicycling.com/showthread.php?t=36334

BUT! Read the whole thing!! Don't use unsealed bearings!!!

Read it or suffer the consequences. I am already
suffering the consequences of poor tolerances!!!

http://www.trdspecialties.com/grade.asp

http://www.nationalprecision.com/miniature-bearings/technical-data/abec_tolerance.php

 

[stinky]

Found this link about breaking down bearing and photo picture essay on teardown.

http://www.motoredbikes.com/showthread.php?38738-Removing-Clutch-Shaft

http://s982.photobucket.com/user/Ron-Becker/library/Chinese HT breakdown?sort=6&page=1

 

[Will122391]

Are you sure you have your bucking bar and ball bearing are in? They fall out sometimes when the arm cover is taken off as seen below (there should be a bar sticking out of the hole).

 

[Jeckler]

The bucking bar and ball bearing do not set the mandrel length that sticks out the clutch side.
Neither does tightening or loosening the inner spring. That sets tension. Part 21 in the OP dictates where the mandrel sits in relation to the shaft. Mandrels can be different lengths, though maybe not on purpose.
I went through a similar experience a month or so ago, so it's still somewhat fresh.

 

[crassius]

as the inner spring is tightened, it becomes shorter exposing more rod - seen it many times (tho sometimes the extra length first shows up at the bucking bar side, but is then pushed thru to the clutch side when the drive cover is tightened)

 

[stinky]

The bucky bar and the ball bearing is in there. The mandrel insert into the clutch shaft is the problem. Took me awhile to figure out the diaphragm, i mean diagram.

Oh and when the clutch assembly(big gear) is pulled, I see no way to remove the chain sprocket on the same shaft. The threads on the bolt on the Chain sprocket side seem to be far
larger than the inner diameter of the chain sprocket. I see absolutely no way of doing like Norman says and driving the bearing out from the chain sprocket side! Or hitting the chain sprocket side and making it come out the clutch side!!!!

Perhaps if the bearings come out as well with the shaft?

I will and have been making a video of my install. The part with the engine will be called
Installing a Motorized bike kit with Tourette's syndrome sufferer, as man I was cursing lol!!
100 degrees and humidity...... blah Everything went perfect, man my
hub gear went on perfectly straight first shot. Then right as I was goin to get the two cycle oil, BAM!! off falls the Clutch cover. Also my lower back had a pinched nerve, so lol, I was cussin!!

From what I have read, actually good luck because I got new bearings, and can regrease the open bearings with good grease, as the Chinese Brown Hog Dripping Grease looks sub par!!!

I ordered 1 flower nut, 1 mandrel post clutch bolt, and two bearings.
Hope thats all I need. Oh and a puller.

 

[Jeckler]

I'll have to disagree with you crassius.
Stinky,
The puller works for both the clutch hub and sprocket. Once both are removed along with the woodruff keys , the clutch shaft can be driven out from the sprocket side. Use a rubber mallet and thread the sprocket nut back on to protect the threads. The clutch side bearing will come out with the shaft.

 

[stinky]

Yep ure right!! I got some "real lighting" on the hub, was trying to read the
bearing rating. And yep, its a very fine line, but it IS LARGER than the threads on the shaft, the chain sprocket. Sorry to spread lies and disinformation..... im gettin old!! Eyes ain't what they used to be!!

Oh and before i fudpuckk my shaft, where are the woodruff keys? Woodrow Wilsons's keys have not been seen in awhile..... How do I take them out before I drift the shaft? Thanks, I'll go look at the diaphragm..... What's it called on here?.......http://www.pistonbikes.com/category-s/7.htm No woodchuck keys i see mentioned.... Chuck Keys's in love....remember that song???

 

[stinky]

Ok all the parts came, and the puller. Now the key way is covered by a nice heavy
spring!!! So how do I get the spring uninstalled/ reinstalled? A vise?? I'll go search forums. Woodruf keys were easy.

Looking at the shaft of the clutch, on the sprocket side I can see where it was
eaten up by a vise. The other side the threaded nut is on, on the spring.

I just wonder if I can get it unscrewed if I can ever recompress the spring to get the
thread started.

Anyone know the shop trick???

 

[stinky]

Ok put the shaft in the vise, and was able to remove the nut no problem. Thread go far
enough out that the spring has no tension when it comes loose.

I put in the new center mandrel torque bolt and pinned it. After I sucessfully reinstalled
everything, I put the bucky bar in, and it stuck out more than before. I uninstalled everything and noticed that the original mandrel's pin hole had a somewhat oval pin keyway, so it could move forward and backwards a little. A little free play. Still it seems that when I tapped on the bucky bar, it was frozen. It did not move inwards any. Perhaps I needed to screw in the flower nut more to draw in the center spring, and pull the ball bearing in further to get the desired clearance.

So now I don't have any idea what to do......... and the bucky bar had gone missin in action, looked half hour for it, nowheres to be seen. So weeks wait for a new part, or I'm toying with cutting the old mandrel up and using that for the bucky bar.

This is gettin to be a royal PIA.

 

[crassius]

that bar won't move until you have all the leverage of the clutch arm pushing it, and how tightly the inner spring is adjusted will have an effect on its movement too

I must have about a dozen balls & bars under benches & cabinets in the shop. They seem to hide well : )

5/16 is close to 8mm if you have a rod you can cut to length

 

[stinky]

Ok cool thanks. I found the Bucking bar. I had it greased really well. And when i cleaned off the spring, i must have thrown down the rag and got it stuck to it. It was in the garbage. Similarly as I started to reassemble, I found the clutch cable retaining pin in the expansion cut near my garage door!!!

Sorry for all the panikey retarded posts. The temperature index was 106 degrees lol!! I get near heat stroke stupid. My hands get oily and sweaty and I can't get a hold of anything!!! After a week I had forgotten that the chain cover partially compresses the
pin in. When I reset the clutch and took the cover back off to pack Bar hole with grease the Bar was in the correct position, in a little further.

For god sakes I shoulda put it together in the winter!!

I want to get started on it again, but my back is killing me from yesterday!!!
So anyways, just settin up electrical connections, gas line, and clutch is all that's left, oh and the guide roller. Almost done! Oh gap the pug durrrrr!!!

I put grease on the ball bearings on the clutch, but right after I run it for first time I'm gonna have to open it up and look to see if it flew all over clutch pads.

I will post links to my video once I have all the cuts compressed and reappended. Gonna have to play with deblocking filters to make it look better. At least video processing I understand!!!!