Page 1 of 1
Bit of a clutch problem
Posted: Mon Nov 15, 2010 5:42 pm
by RAW1
Hi - I picked up a project bile at the weekend that has been sat for 5 years but was apparently reunning fine when stored. I have bled the clutch today as there was no pressure. The sprocket cover was detached at the majority of the bolts missing. I have managed to secure for the moment and the pressure at the lever is good (I can hear the push rod moving).
the problem is that the clutch is not dis- engaging properly and neutal is where 4th should be ?. any thoughts ?
cheers
Re: Bit of a clutch problem
Posted: Mon Nov 15, 2010 7:47 pm
by kiki231
ahhh-- that'd be a false neutral there, RAW -- usually caused by a deflected shift fork , or a damaged gear (severely). I am assuming your normal neutral still exists? If not, then there is a tear down in store for you ....... a lot of work, but all fun, and not terribly difficult.
I would bet the prior owner experienced the same, attempted a repair, then gave up.
THe clutch is an easier fix. Usually, after sitting for a long time, the fibre and metal plates stick to one another, even though you release the spring pressure by pressing the rod (disengaging the clutch). Raise the rear wheel, have someone hold the clutch lever all the way in (or tie it back with a string), shift it into a low gear, and, using drive line slack, start banging the wheel against the tranny (do this gently) -- you are trying to "unstick" the plates on the clutch. the stickiness is a problem up here in eastern canada, where the humidity causes the oil to foam microscopically around the clutch plates, making a layer of film that holds them together -- so as you pull the lever, you push the rod, which presses the springs away from the mulit-layered sandwich that is the clutch, allowing the alternating layers to spin autonomously from their adjacent components. When they stick, its like lifting the top off a sub sandwich, and all the layers stick to the top as you lift.
For us up here, when you haven't ridden your bike in a while, you pull the clutch and hit the starter, the bike jumps a bit event though the clutch is not engaged. Or if you start the bike in neutral, then hit the shift lever and the bike pops forward a bit-- all sticky plates.
TO work on the tranny to fix the neutral (after you fix your clutch-- because, God willing, it might go away when all is corrected), you will need to access it from the bottom of the case. You will need a service manual. And you should do some research first to make sure you are really clear on how the tranny works. It is very simple when you see it in person , and when you open the bottom, usually you can see if there is a prob with the gears themselves. The shift forks are very precise, so it is difficult sometimes to "see " a bent one. Sometimes you need to place them on a flat surface.
Re: Bit of a clutch problem
Posted: Tue Nov 16, 2010 2:03 am
by RAW1
thanks for this - I will take a clser look today. The normal neutral is not there either which is odd. You can sometimes find it but then you can heear something click into place in the box then its back in gear ! could this be anything to do with the clutch housing, spacers incorrect fixtures (all were missing), master or slave cylinder ?
Dont suppose anybody has an exploded diagram of the clutch mechanism ? My manual is in the post and another week away
cheers
Re: Bit of a clutch problem
Posted: Tue Nov 16, 2010 4:58 am
by kiki231
from what you say, i would guess the most likely culprit is one or more bent forks. There are 3 shift forks, left , right, and middle. So you may want to tackle that prob right away-- (ie-- fixed clutch wont fix it)
As far as the shifting problem being caused by the clutch, the answer is no. The clutch may have contributed to it (for example a missed "power shift" is really tough on the tranny-- in particular the forks.), but right now, the funny things it is doing are not related to the clutch not disengaging. You should be able to turn the wheel slowly by hand and shift thru the gears as you do it. The tranny is always attached to the wheel, so the turning wheel is what allows the gears to engage laterally.
As far as the clutch components, there may be a few photos kicking around here somewhere. And regarding the tranny, you will probably just need to remove the shift drum and fork/fork shaft.
chris
Re: Bit of a clutch problem
Posted: Tue Nov 16, 2010 9:14 am
by McFizzer
Yeah sounds like the shift forks for sure.. You're M/C is good(check), Slave is good (check).. Have you taken the pushrod out and inspect it?(under the front sprocket cover where the slave pushes in), the plates would un freeze with an hour of normal riding and an oil change. You can inspect the forks by removing the clutch and flywheel but you can't inspect the trans. You would think Mr. Yamaha could make it simple on us and just let us drop the motor, flip it, and split the botom case...NOPE. you have to take the head off and completely tear down the motor as there are I believe 3 bolts that are under the head..
Have you ridden it like this? When your manual comes in, take the time and pull the clutch out and inspect the shift forks for damage. if its problems with your actual trans and the gears then even fixing the shift forks wont help.. maybe for a little but it'll just fook the forks again and your in the same boat. Hey maybe you got lucky and the PO replaced the shift forks in the wrong order? Im not sure if that can effect it but while in there it doesn't hurt to check, as Chris said, theres Left, Middle, and Right.
Let us know how it goes
Re: Bit of a clutch problem
Posted: Tue Nov 16, 2010 9:34 am
by kiki231
McFizzer wrote: You would think Mr. Yamaha could make it simple on us and just let us drop the motor, flip it, and split the botom case...NOPE. you have to take the head off and completely tear down the motor as there are I believe 3 bolts that are under the head..
ouch!! Sorry RAW, i thought you could access it from below.
Just the same, still a rewarding process.
Re: Bit of a clutch problem
Posted: Thu Nov 18, 2010 6:25 am
by RAW1
Oh man - If the box is spannerd I might just be inclined to drop another engine in. I would be comfortable enough with that but I dont fancy stripping the motor - I will let you know how it goes. cheers
Re: Bit of a clutch problem
Posted: Wed Nov 24, 2010 4:07 pm
by RAW1
result - soaked the clutch plates that were stuck together - all working weel .The problem with the gearchange was the selector lever - the spigot marks were not lined up - rotated it through 90 degrees and hey presto !! niceeeee. the kinda fix me likes
Re: Bit of a clutch problem
Posted: Wed Nov 24, 2010 8:16 pm
by kiki231
Now THAT is good news!
I love it when a plan comes together!
Easy fix-- that is great.
So you are good to go?