clutch issues

[Ace B]

Hello,
After I put my 92 model 100 cc engine back together, activating the clutch handle wouldn't disengage the crankshaft from the gears. I put the bike on a stand, pulled off the clutch cover and depressed the clutch with my hands while my son spun the rear wheel while it was in gear to confirm my first result and still the crankshaft was activated by the spinning rear wheel. The clutch was engaging fine before I took the engine apart and I never dismantled the clutch. I only removed it from the engine and replaced it. What could I have done wrong?

[Pep]

Hi Ace - so did you have the bike running when you tried this?
Sometimes those plates can be a little sticky after a tear-down - there are tips on this forum for addressing that. A "dry" test is not always indicative of failure.
Also, do you have proper free-play at the clutch cover lever (without the cable attached)?
There are a couple of thrust washers (thick inner and thin outer) that run along the pinion and rotor gears - see parts diagram - just to make sure all is in place...

[Ace B]

Hi Ace - so did you have the bike running when you tried this?
Sometimes those plates can be a little sticky after a tear-down - there are tips on this forum for addressing that. A "dry" test is not always indicative of failure.
Also, do you have proper free-play at the clutch cover lever (without the cable attached)?
There are a couple of thrust washers (thick inner and thin outer) that run along the pinion and rotor gears - see parts diagram - just to make sure all is in place...

Thanks for the tips, Pep. I know now what I did wrong. I put regular synthetic oil in after reassembly without knowing that wet clutches require a special kind of synthetic oil made specifically for wet clutches. The regular oil must have frozen the discs. Lesson learned.

[Ace B]

Thinking I needed new clutch discs, I ordered some but I got the wrong size. The 4 existing ones were about 0.078" thick and the new ones were 0.10" thick. I had already soaked the new ones in oil and installed them before I figured out they were the wrong size. Then I decided to take one of the new ones out and see how it worked since 3 of the new ones would be about the same thickness as 4 of the old ones. What I found puzzles me--with the 3 new discs, if I don't tighten the clutch down to the recommended 250 torque pounds, I can put it in gear, squeeze the clutch and roll the bike back and forth very easily, showing me the clutch is engaged; however, with the clutch engaged like this and when it is still in gear, if I kick down on the starter, it will thrust the bike forward as if the clutch is not engaged. I don't know why that would be. Do you?

Also, once I torque the nut to 250 pounds and try to roll the bike back and forth while it is in gear and while squeezing the clutch, the bike will not roll and behaves as if the clutch was not engaged. Incidentally, I did check to see that the thrust washers were in place. Thank you for any help on this.

[MWL]

The model 92 does not have primary kick. It needs to be in neutral to kick start it. Also, it is 250 inch pounds on the clutch nut. That is about 21 foot pounds.
Mike

[Ace B]

The model 92 does not have primary kick. It needs to be in neutral to kick start it. Also, it is 250 inch pounds on the clutch nut. That is about 21 foot pounds.
Mike

Thanks for the reply. I didn't know the 92 doesn't have a primary kick. I meant inch pounds in my post. Sorry for the typo.

[Zyx]

Specifications for the 100B show that the friction disc thickness when new is supposed to be 0.10" or 2.54mm, so you got the right ones. There should be four in the stack. Everything you have described so far is quite normal for a wet clutch. The reason the clutch allows free wheeling when you use only three discs is because it is slipping. If you built it that way and tried to ride it you would find the clutch action very light and it would slip, probably so badly it wouldn't pull itself up a hill. Properly assembled, with the clutch pulled in and in first gear and the engine not running, it will be very difficult to push the bike. On loose terrain or mud, the wheel will just skid. Overall ratio in first gear with trail sprockets is around 42.4 to 1. Driving the transmission backwards, as when pushing the bike in gear with the clutch pulled, you are trying to spin the primary gears 42 times for every revolution of the rear wheel. Wet clutches drag normally. It is extremely difficult to drive a Hodaka transmission in gear engine off clutch pulled unless you are in fourth or fifth gear where the ratio is more in your favor. In fifth, it is one to one, which is doable.

I think you are expecting something that isn't there normally, that is, a free wheeling clutch. The clutch only releases enough for the engine to overcome the drag when running, not enough to allow you to push the bike in low gear or turn the gears manually. Try putting it together with the correct count of the new discs and give it a ride, see if it doesn't work.

[BrianZ]

There seems to be some confusion here. Just for clarification, the model 92 has the thinner .078" friction clutch plates and the model 92B has the thicker .010" friction clutch plates.

Brian

[Ace B]

There seems to be some confusion here. Just for clarification, the model 92 has the thinner .078" friction clutch plates and the model 92B has the thicker .010" friction clutch plates.

Brian

Thanks, Brian. Yes, my 92 has the thinner .078" plates.

[Ace B]

Specifications for the 100B show that the friction disc thickness when new is supposed to be 0.10" or 2.54mm, so you got the right ones. There should be four in the stack. Everything you have described so far is quite normal for a wet clutch. The reason the clutch allows free wheeling when you use only three discs is because it is slipping. If you built it that way and tried to ride it you would find the clutch action very light and it would slip, probably so badly it wouldn't pull itself up a hill. Properly assembled, with the clutch pulled in and in first gear and the engine not running, it will be very difficult to push the bike. On loose terrain or mud, the wheel will just skid. Overall ratio in first gear with trail sprockets is around 42.4 to 1. Driving the transmission backwards, as when pushing the bike in gear with the clutch pulled, you are trying to spin the primary gears 42 times for every revolution of the rear wheel. Wet clutches drag normally. It is extremely difficult to drive a Hodaka transmission in gear engine off clutch pulled unless you are in fourth or fifth gear where the ratio is more in your favor. In fifth, it is one to one, which is doable.

I think you are expecting something that isn't there normally, that is, a free wheeling clutch. The clutch only releases enough for the engine to overcome the drag when running, not enough to allow you to push the bike in low gear or turn the gears manually. Try putting it together with the correct count of the new discs and give it a ride, see if it doesn't work.

Thank you, Arizona Shorty. I will keep this in mind after I put in the new discs. The old ones were 0.078" so that's what I need to replace them with. What happened before was that when the bike was running with the clutch pulled in, it would jump into gear and stall as if the clutch was not engaged. Perhaps the new correct discs will fix that problem.

[taber hodaka]

I pull in the clutch lever and kick the engine over if that does not break the clutch plates free try a hill in hi gear. I break the clutch plates free before I put it in gear. -----------Clarence

[Zyx]

You are right, I was looking at 92B.

Everything else I believe is correct. Pulling the clutch counteracts the springs enough to release the clamp load but does not result in a freewheel clutch.