DaVinci856 Posted August 28, 2010 Posted August 28, 2010 Hi There. Well, now that I've gotten the 175 running fairly well, I have a relatively minor problem that just plain bugs me. From another thread you may know that I replaced the clutch basket after accidentally braking one of the ears off while removing the primary drive gear. Because of that, I used two of the existing metal clutch discs to make a removal tool and ordered two new ones as replacements. The new clutch holding took worked fine, and all of the other work went OK as well. However, after re-assembling everything, the first time I tried things, the clutch did not release at all no matter how the clutch lever or pushrod was adjusted. (Neutral was fine, but first gear was totally engaged no matter what.) I then removed the right side cover and stripped everything off of the new clutch basket. While stripping it, I noticed no issues at all - nothing was stuck together at any step. I then put everything back. I made sure that all of the rubber rings had the "open" end facing away from the center of the basket, and thought I put all of the metal and friction plates back in the same order. After complete re-assembly (including a check of the push rod and lever again) the clutch worked. However, there is a slight drag to it even when the lever is squeezed all the way in. By that I mean that if the clutch lever is squeezed all the way in, the bike is never quite all the way out of gear - it wants to move a little. Since I have no idea what I changed, I'm at a loss. The only thing I could think of was the pressure plate screws, but I checked them when I replaced the plate and put them in just barely snug to the metal as the manual describes. The spring height is perfect as far as I can measure. If I try to adjust he clutch lever to make the clutch release all the way, it appears to work, but I know doing that is wrong - there should be a small amount of play in the lever and the push rod should be adjusted until it seats and then backed out a tiny bit as per the manual. Both were adjusted exactly as per the shop manual. Does anyone have any ideas as to what in the world I might have done incorrectly in the clutch assembly? BTW, I'm using Yamalube for the crankcase oil, so it's not that. The clutch worked fine before the 2 plates were replaced, so I do have a good starting place. I will point out that the new plates (from Yamaha) did not look EXACTLY like the originals; they were not completely circular, but had small tabs sticking outside along the circumference of the circle them that the originals didn't have. The new basket is a NOS (New Old Stock) piece, so I know that's fine. Any guesses would help. Thanks.
Moderator Airhead Posted August 28, 2010 Moderator Posted August 28, 2010 it says in my Haynes manual that one possibility of this would be "Clutch assembly loose on mainshaft" ? I know the type of plain plate you mention they are designed to reduce clutch niose and because some of the plate is cut away then when in use centrifugal forces stop the things from rattling about. With a full set of them you would assemble with the tags at 60 degree intervals so it balances up and does the full 360 degrees with all plates used. As you have only two I guess you should assemble them with the tags 180 degrees (opposite) each other for balance. Also check oil level. Then there is clutch adjustment, not sure which yours is but some are a screw and locknut in the centre of the pressure plate, to adjust this type it is an oil drain job. slacken cable, screw in adjuster until contact is felt then back off a little, you should feel a little free play at the engine mounted lever. Then do your cable adjust. The later type is an adjuster and locknut near the sprocket, here is what my manual says about that one.
DaVinci856 Posted August 28, 2010 Author Posted August 28, 2010 Thanks OG. Somehow I suspected you'd be standing by somewhere and ready to help. My clutch adjustment is just the easy to do pushrod screw and locknut next to the sprocket and the lever adjust. However,what you say about the metal plate tab position makes a lot of sense and would explain the change. Unfortunately, I made a poor decision in 70's and got the Clymer manual which mentions nothing about the tabs. Since I've triple checked the oil level, I'll be pulling the right side cover off to check the tab position as soon as I get another cup of coffee this morning and check back in. It's supposed to be great weather here today and the hope is to spend a lot of it on two wheels.
DaVinci856 Posted August 28, 2010 Author Posted August 28, 2010 Problem Solved! I pulled off the right side cover and took a look at the orientation of the two replacement clutch discs Below are pics of two of the discs and one of the originals. As you can see, the two new discs had the tabs at about 11 and 12 o'clock positions. The old ones, of course, were completely round. I moved one of the two new disc's tabs down to the 6 o'clock position and I also tried something else - I know that a cardinal rule is never to change more than one thing at a time, but I was in a mood to break rules today. When I first took the basket apart after its 30 year nap, I could have sworn that it started with a rubber ring before the first metal disc. I thought it was odd, because all the CT3 diagrams I'd seen had the rubber ring after the first metal disc. But anyway, I left it as it was. Well, after looking at many different sources, I decided this time to also move the first rubber ring after the first metal disc because the function of the rings is supposed to be helping the clutch disengage (but everything I've read ALSO says that the rings are not required). In any case, I put things back together and everything works beautifully. I'm not positive which change fixed things, but It is, nonetheless, fixed. Thanks for the help. Steve.
Moderator Airhead Posted August 28, 2010 Moderator Posted August 28, 2010 When I first took the basket apart after its 30 year nap, I could have sworn that it started with a rubber ring before the first metal disc. I thought it was odd, because all the CT3 diagrams I'd seen had the rubber ring after the first metal disc. But anyway, I left it as it was. Well, after looking at many different sources, I decided this time to also move the first rubber ring after the first metal disc because the function of the rings is supposed to be helping the clutch disengage (but everything I've read ALSO says that the rings are not required). In any case, I put things back together and everything works beautifully. I'm not positive which change fixed things, but It is, nonetheless, fixed. Thanks for the help. Steve. Good stuff Steve, but I'm not sure what youre saying here. My DT175 is Pressure plate Friction plate Rubber ring plain plate Friction plate Rubber ring Plain plate etc etc ending in friction plate rubber ring Clutch centre is this yours?
DaVinci856 Posted August 29, 2010 Author Posted August 29, 2010 Understood. What you describe is pretty much as I believe mine was before I did anything (with the rubber cushion ring against the hub). The only real difference was that what you describe is from the outside in, and I described it from the center of the bike out. The friction plates' inside diameters are pretty much outside of the rubber rings if I remember this correctly, but the metal plain plates are always touching the rubber rings. The way I looked at it (from building it from a bare clutch basket and hub out): First I thought I saw: Empty clutch hub rubber ring plain metal plate friction plate metal plate rubber ring friction plate metal plate rubber ring etc, etc. I changed it to (building it from the inside out): empty hub metal plate rubber ring friction plate metal plate rubber ring friction plate etc, etc. The big difference, of course, is that I started with a metal plate against the metal of the clutch hub this time rather than a rubber ring against the clutch hub. This is as it is pictured in some, but not all of the clutch designs in my Clymer manual, but is exactly how it is listed in the parts lists of the web sites that I checked out for a CT3. You had me going there for a bit trying to figure out how your description was possible, but finally I figured it out while I was writing this. Yours is a later model, so after staring blankly at the computer screen for a while, I looked on line at a parts list. You have 5 metal plates, 6 friction plates, and 6 rubber rings. I only have 5 of each type of thing! You start from the pressure plate with a friction plate and end against the hub with a friction plate. Since I don't have as many, I have to end differently. I can see how the design of a DT175 is an improvement, but I have to work with what I have. Steve.
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