Posts
318
Joined
6/19/2014
Location
Denver, CO
US
I have owned a few dozen bikes and every one of them drags the clutch a little when the clutch is pulled in. Doesn't matter if the bike is off road, dual sport or road. Doesn't matter how far the clutch pulls. Doesn't matter how old or new the bike is. Every one of them drags the clutch a little when the lever is pulled in. Should be noted I always run dinosaur oil in my trannys.
I am wondering what the deal is. Do clutches a always drag a little due to oil viscosity and rpms creating enough friction even if the clutch plates are separate?
Would synthetic oil slip better to overcome the drag when the clutch is pulled in?
Been thinking to maybe try tranny fluid instead of oil in my dirt bike if it offered more slip with the clutch pulled in and still protected the tranny same as oil. I have heard its OK to run tranny fluid but don't know if this is for only for Sunday rider putt putters or hard ripping riders too. Would running tranny fluid actually help the drag issue? Is tranny fluid really OK to run in a hard driven dirt bike engine?
I am wondering what the deal is. Do clutches a always drag a little due to oil viscosity and rpms creating enough friction even if the clutch plates are separate?
Would synthetic oil slip better to overcome the drag when the clutch is pulled in?
Been thinking to maybe try tranny fluid instead of oil in my dirt bike if it offered more slip with the clutch pulled in and still protected the tranny same as oil. I have heard its OK to run tranny fluid but don't know if this is for only for Sunday rider putt putters or hard ripping riders too. Would running tranny fluid actually help the drag issue? Is tranny fluid really OK to run in a hard driven dirt bike engine?
The Shop
I don't want to open a can of worms here, but try Shell Rotella T6 as I have seen less clutch drag with it than any other oil.
Paw Paw
I have been running Rotella T 15-40 dinosaur oil. I think I will try the 5-40 T6 synthetic to see if there is a difference.
My clutch feels good on the track but when kicking into gear for the first time of the day, it hits pretty hard. I've gotten Bel-Ray 80w gear oil ( I have honda split engine/trans oils ) to reduce this quite a bit, but it's still there.
I think I have grooves in my clutch basket, Only one way to fix that.
-My 97 rm250 had a creeping clutch, plus it was weak and acted soft when hot.
-I drilled two TINY holes on the clutch hub where the metal clutch plate spines ride. Every single spline channel, staggering the holes.
-I drilled 4 6mm holes in the main basket, on the back where the gear rides.
-i drilled one 6mm hole on every basket ear, and chamfered all holes.
After this work, I could put my bike into any gear with the engine no running, and the bike would roll as freely as if it were in neutral. Totally fixed my mushy clutch action as well.
The moral to the story is that the plates won't separate cleanly if they're not getting enough oil. I plan o doing this to my new 08 rm250 as well. It totally fixes clutch issues due to not enough lubrication. I did this same fix to my 2000 kx250, and a friends lt250, and it works every time.
Most Common:
Plates sticking together after bike sitting for weeks (temporary problem)
Basket notched
Inner hub (boss) notched
Plate(s) warped - steel or fiber
Pressure plate warped
Too much freeplay adjusted into cable/lever
Possible:
Stretching or flexing cable
Worn thrust washers (basket and/or hub wobble)
Worn basket needle bearing and/or spacer (basket wobble)
Thrust washers too thick (hub not spinning freely from basket)
Heavy/sticky oil
Basket came loose from gear (basket wobble)
Main shaft bearing bad
Not common, but still possible:
Main shaft bent
Actuating arm not moving through centerline parallel to push rod (or pull rod)
Excess slop in lever: Perch pivot and/or cable pocket
Coil binding of springs
Pressure plate hanging on springs
Clutch stack too thick
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