125-200cc Clutch slip on 165

Right on guys. As always I say do what you believe in and what has been working for you. I have learned over the (more recent) years that my view of "correct" may not fit everyone's situation or use, that the same materials and designs produce different results for different people. We sure do use our machines in vastly different conditions and ways!!

I have personally proved the loss of clutchpack pressure myself. Back when I was one of the "top dogs" locally in 125A and 250A(that alone dates it, now 250A and 450A!!) , my 125 starting slipping bad in practice. I had fresh OEM springs (Honda CR125) but no plates. Threw the springs in and got through the raceday with no more slipping. Replaced the pack later and it was beat.

Some interesting info on the very real occurance of both spring fatigue and spring relaxation, both of which affect clutchpack pressure:

http://www.rockfordspring.com/relaxationofsprings.asp

http://www.rockfordspring.com/springfatigue.asp

I feel that in this bike IN PARTICULAR, it has very little wiggle-room for the springs, as they are just barely adequate when new, for the way I ride. Again, disregard if you never have the problem, but I mention all this because the OP IS having a problem! The springs are cheap compared to the clutchpack, so it makes economical sense to replace them.

Marc, I agree with the "theory" of what you're talking about, and maybe if you're right on the edge it can happen. However, as shown in those links, the amount of relaxation we're talking about is only 1-5%. On the fatigue, it's impossible to say if we have an issue unless we have a bunch of engineering data about the springs. Also, note that the number of cycles to failure is on the order of 1 million; even at 1000 clutch actuations per ride (every 7 seconds of a 2-hour hare scramble!), it would take 1,000 rides (maybe 30,000 miles?) to get a spring to fail. Unlikely anybody here rides a 2-stroke this much!

So there is no notching on the basket
I have nt really ever smelt burning and the plates aren't blue -would that be when hot?

I am not sure if the worn friction plates are really worn too much or if issue is related to the asv lever

Any thoughts on wear and pics?

As i said I will also do a flush and try best quality oil.
If springs are cheap enough will get new ones with plates if i need them

Good convo guys!

RD if your measurements were accurate and you are below min spec on the frictions then by all means replace the pack and springs, it is probably the problem. Remember, as the pack wears it gets thinner, which effectively is reducing preload on the springs also. I would definitely go back to a stock perch/lever with stock freeplay, at least until you establish a baseline to work with on the new clutch. That info, combined with all that people have shared here, will give you the knowledge to make an educated decision on wether the ASV is going to work for you properly. Kelly's tip on oil is huge, only use an oil without friction modifiers. If you are unsure what to use, ask here or only use a 2t gearbox-specific oil. If it says "energy conserving" it most certainly has friction modifiers and is the enemy of clutches. Even if it only got used once, it compromises the clutch for ever. Perhaps this happened in the distant past?

Yes I think my oil choice has been without that knowledge in the past
The wear would have been over the last few years as a 125 then 144 and I guess the torque of the 165 is showing the issue up

Cleaned up the plates with some emery cloth and put in some new quality gearbox oil
Changed clutch lever which allowed me to reduce middle cable barrel about 10mm
Clutch seems to work perfectly now
Message - dont use ASV. levers.

These clutches are pretty indestructible if you ask me
I had with my last overhaul notches in the basket which I filed out
I have a new basket on the shelf now but still don't see the need to replace it

I do use the bike where it is made for and do respect the oil changes and so, but its amazing how much this little engine is taking the load

Robert-Jan

Yep.
Re measured the friction plates and they were all 2.9mm so only 1mm of wear in 100 hrs or so
Went on a big ride in the wet and she is going real well. Impressed a few people with its grunt
Mind you another guy on a new wr125 was there and rode his bike up hills better than most on 300s

No issues on mine with ASV lever. I get full release and full engagement. No matter though as I have my hydro clutch on the bench waiting to be installed!