Clutch problems - 1976 250 MC5

[Lloyd Boland]

Slowly but surely, the clutch pull has been getting harder and harder.  I have had to tighten the adjuster on the pirch every once in away.  No kinks in cable.  Pulled cable off and it moves very smoothly.  If I pull real hard now, I can get the clutch to work but very little play.  It feel like I am at the end of the pull and it just barely engages.  I had a Yamaha once that had an internal actuating rod that the end flattened out and it had the same feel.  Is this a similar problem with the MC-5?
I looked at the parts manual and it looks like there were 2 different types of actuating rods; one system with 2 rods and a ball bearing in the middle, and one system with one long single rod.  If these flatten out, is this what I should feel and how do I know which system I would have?  Thanks in advance.
Lloyd Boland

[tmc3c]

Hi Lloyd,
I have a 74 250 motor and I had the same problem. I had to grind a bit off of my push rod to obtain the distance at 0 clearance illustrated on page 6 of "Instructions for the Penton sports motorcycle 175-250-400. Do you have this book?



Thomas Carmichael


1970 125 Six Day
1976 250 Hare Scrambler

[Lloyd Boland]

I have the parts manual and the repair manual from Al Buehner.  I am at work right now.  When I get home I will look to see if this is the book you are referencing.
Thanks.
Lloyd

[gooddirt]

My 74.5 250 did the same ; come to find that the rods had fused to the ball . The rods also would not slide all the way in their slot; as they had fused to side walls at some time past. Take the off the actuating cover and tilt the bike or motor and the rod and or rods and ball should slide out ; if not maybe fused [xx(] .  LG

[gooddirt]

quote:Originally posted by gooddirt

My 74.5 250 did the same ; come to find that the rods had fused to the ball . The rods also would not slide all the way in their slot; as they had fused to side walls at some time past. Take the off the actuating cover and tilt the bike or motor and the rod and or rods and ball should slide out ; if not maybe fused [xx(] .  LG

[Lloyd Boland]

Thanks guys.

Thomas, yes I have the book and will try to take apart this weekend.  Thanks.

LG, thanks for the "Heads-up" on the possiblity of fusion.

Is there a way of telling before taking the actuator off to find out if I have the older model with the 2 rods and ball bearing, or the "newer" model with the long rod?

I understand the logic of adding an additional ball bearing between the 2 rods and grinding down the rod to get the right length.  What is the fix if it is the single rod type?

Thanks for all the help.
Lloyd

[tomale]

It seems resonable to me that if the actuating rods are dirty and does not move freely then it can cause the clutch to feel alot stiffer than it should. and I know that you have taken off the clutch cable to see if the cable moves freely but just because it moves freely when there is no tension on it does not mean it is not dirty.. and in need of service..I have had several bikes that acted just like you described and it turned out to be the cable... even a brand new cable needs to be oil throughly to work its very best. and a cable that has been used for awhile collects dirt way up inside of it. the solution is pretty easy.. take the cable off and flush it out with some kind of cleaner.. carb cleaner or something along that line, once clean allow it to dry and then oil it. make sure you use something light. I personally use Tri flow but it tends to get dirty pretty fast... Maybe some of the other guys have a better product...

Thom Green,Still crazy after all these years!
76' 250 MC5 (orginal owner)74'
250 hare scrambler (project bike)
72'sixday (project bike)

[Rocket]

Lloyd
If you have the (2) piece assembly, you will be able to pull out the clutch rod from the actuator side, if it is the one piece, it has to be removed from the clutch side.
Rod

[gooddirt]

The one piece rod actuator looks like a big backwards  letter C and has a clip on chain protector both one and two piece rods come out on the actuator side; as the one piece rod  has a bearing cup on the end of it so there is no way to pull it through . I'll bet you have the two piece. I do have some NOS two piece rods no balls. LG

[Steve Minor]

We used to service our cables (as routine maintenance) with solvent to clean them and then Dri Slide. I suppose it's still available.
 
Here is a paragraph I Googled:

"Dri-Slide® is applied wet. Gravity distributes the lubricant within the cable sleeve thoroughly and evenly over the entire cable, penetrating even the smallest spaces, and leaves a dry lubricant bonded to the cable surfaces after the carrier evaporates. Because Dri-Slide® is a dry lubricant, it does not attract dirt, sand, or dust, thereby promoting smooth operation of controls and longer intervals between servicing."

I got the above paragraph from: https://www.russack.com/




Steve Minor
Wilmington, NC

[Lloyd Boland]

Thanks for all the suggestions.

Thom, I went back and looked at the cable again, and it is in pretty good condition, but could be replaced.  

When I pulled the clutch actuating mechanism off the right side case and the bearing fell out of the cage.  Obviously I have the single rod application.  Unfortunately I didn't get a close look at which way the bearings sit in the cage.  The bearings have 2 different sides, one side has a small washer type surface like a bearing race, the other side is the surface of exposed ball bearings.  After turning it back and forth a couple of times, I think the ball bearing surfaces go into the cup and the flat side that has the flat washer type surface faces outward toward the actuator mechanism.  Does anyone know for sure?

I pulled the rod out and it did not appear to have any deformation or shortening.  And before taking it apart, it looked like there was plenty of distance for the external actuating rod to move (it did not hit the case when fulling engaged with distance to spare before it would hit the case).  I then looked at the actuating mechanism itself.  It was still very difficult to move the actuating arm even after I had removed it from the bike. That was the problem.  Over the years plenty of GUNK and some corrosion had occured on the internal parts of the actuating mechanism.  I pulled them apart, cleaned them well and put a light coat of grease on the inside.  They move very easily now.  

Before I put everything back together, I was hoping for an expert advice on the position of the bearings in the cup.  Was I correct, that the bearings face into the cup and the flat washer surface faces out?  I would hate to put it back together and bend or tweek something by making a stupid error.

Thanks again for all the suggetions, it truly is motivating to have all this help.

Lloyd

[Young Ted]

Lloyd - You are OK with your thinking on the bearing, as the pin will be the ID part. As for the actuator arm binding, I'd check as to why it did not get oil from the engine.