Tuesday, February 23, 2016

Minor work on Scarlett

You're probably saying, "oh oh, here we go again", something's wrong with Dom's URAL sidecar rig.

Fear not, it was a relatively minor thing and I believe already fixed.

Symptoms:  when the engine got during city driving, the clutch would not fully disengage when stopped at a stoplight and in gear.  I would have to kick the transmission lever into neutral to prevent the rig from trying to move forward and bogging down the engine.  The clutch, otherwise, behaved just fine while moving.

I got her home where she stalled while I waited, with the clutch lever pulled all the way in, while the garage door opened so I could get her parked to examine things.

Tried adjusting the clutch cable several times, but no matter how tight or loose I got it set, it would try to move forward after a few seconds and stall out.  Dammit.

I telephoned Randy, the dealer/owner of Unique Rides in Fort Collins and describe the symptoms. Along with removing the clutch cable to check its length against the spare cable I had on hand, he recommended checking the thrust ball bearing assembly which is part of the clutch actuating mechanism on Scarlett. (see diagram below)

So I loosened up the clutch cable in order to remove the clutch actuating lever and get at the thrust ball bearing assembly:  parts 4 through 7 in the diagram below.


Once I had removed the Clutch Release lever (12) and slider (9),  I extracted the thrust bearing assembly (14). It became immediately obvious that this was the problem.

Two Tip Aseemblies (14)
The one on the left is good:  Two washers sandwiching a ball bearing
race assembly(5).  The one on the right is missing the ball bearing race assembly
and half of the lower washer!

Another view of the broken washer

I did not find the missing pieces inside the cavity where the assembly is meant to be.  Randy is guessing that the pieces ended up at the bottom of the clutch housing (we hope).

I had an old tip assembly which had a slight wearing of the end where it contacts the clutch actuating rod:

Again, left one is the one with the good ball bearing assembly and washers but
its slightly worn down on the end of the clutch release rod  (1) as you can see.  \
The right one is the one with 
the missing ball bearing assembly and damaged washer.

So, I've asked URAL for a warranty replacement of this assembly, we'll see what they say.  In the meantime, I transferred the ball bearing assembly and washers from the one on the left above to the one on the right above.

Per Randy's advice, I used blue Loctite to secure the screw that holds the washers/ball bearing race in place on the rod tip.

I put everything back together, re-installed the clutch cable since it appears to be good.

I also discovered the spare clutch cable I've been carrying is 1.75 inches shorter than the existing cable, so its too short to use on the rig!  Randy is checking into this to see if there's a new part number.

I did a brief check of the clutch action and all seems OK right now.  A test ride to follow.

Fun times, the life of a URAL owner.

Update: 24FEB:  Took Scarlett out for a long test ride, the creeping behavior is still there once the engine gets hot.  Sigh.  Now debating whether to try and remove the clutch actuator rod to see if the failed thrust washer assembly aka throwout bearing, caused it some damage and is preventing it from pushing on the clutch plate fully in order to disengage it.

Weird part is that it only happens when its hot from say city driving.  Hmmmm.

6 comments:

RichardM said...

How does that little bearing get lubricated? Just from the initial assembly or is there some path for transmission oil to get there? I was planning on replacing the throwout bearing and I'm guessing that it is the subassembly in your photo.

Charlie6 said...

There is apparently an oil channel from gearbox to the throwout bearing area, but it's believed by some to be "insufficient " by some, especially after a new install it turns out. The parts catalog calls it tip assembly so that's the name I used btw. It's 14 in the pic.

I will be uninstalling it again to lube the bearing with some wheel grease before reinserting.

Note, it's rumored to be pricy, the previous version was $90! I'll ask Randy for sure.

i will forward u some info from a soviet steeds member.

Spat said...

Glad it that's all it was, ride on bro.
I found out recently that my spare clutch cable is about 1.75 too long. Imagine that and imagine that me off all people carry a spare.

Charlie6 said...

Spat, you carrying spares? What's up with that?

If your spare cable is 1.75" too long, we should get together and trade perhaps....

Richard James said...

That's the powerful post. I have Honda 850 CC. Sometimes I cross the meter of 150 in local roads. Anyways I really enjoy it. Thanks

Charlie6 said...

Richard James....not sure what you meant but thanks for commenting.