Metal Tapping Sound from Engine

[jbfla]

Originally Posted by detours

I wonder if there was a miscommunication about CSC finding a shop. ....

Thanks Detours.

There was a miscommunication as you suggested.

CSC has clarified the issue about assisting in finding a repair shop:


"CSC policy is to help you , if needed, to find you a local shop.

You have the liberty to go where you want.

If you don't know of any shops, then of course CSC will do its best to provide options."


I have edited and amended my above post to reflect the clarification.

jb

[SpudRider]

Thanks for posting the clarification, and editing your previous post.

[jbfla]

I contacted CSC again this morning, and was assured that they will do whatever is

necessary for me to be a 100% satisfied customer.

That is good news.

As of now, the RX3 is going to CA at my expense.

Regardless whether or not a local shop can be found, I feel that CSC is the best choice to diagnose and fix the problem.

jb

[Lee R]

Jbla, I'm glad they are pledging support. Hopefully you get it back in perfect shape!

[jbfla]

TheRX3 was picked up and loaded for shipment last week.



Tied down to palette and strapped to side wall of truck:




From here it went to the shipping terminal, then was transferred to a semi truck for the cross country trip, where it was transferred once again to a smaller truck for delivery to CSC.


The engine was removed from from the bike, where it was found that the surfaces of the exhaust cam lobes were severely eroded/damaged.

The cam shaft and associated parts were replaced.

Gerry, said he has not seen this condition before, and an exact cause has not yet been determined.

This reinforces my decision to bear the expense, and have the bike shipped to CSC, where they have to expertise to find and repair the problem.

jb

[Weldangrind]

That was certainly the right move.

[Lee R]

Thats strange, do you have pics? I wonder if a small bit of sealant from break in clogged part of the oil lubrication system.
Good decision to have it shipped!

[SpudRider]

Thanks for posting the update, JB. X3 on the decision to ship the bike to CSC.

It sounds like a defective camshaft to me. Is CSC doing the repairs under warranty coverage?

[CSaddict]

Certainly sounds like a warranty issue.

[jbfla]

Originally Posted by SpudRider

Thanks for posting the update, JB. X3 on the decision to ship the bike to CSC.

It sounds like a defective camshaft to me. Is CSC doing the repairs under warranty coverage?

Yes, Gerry said the warranty would cover the repair....

It sounded like a defective part to me, or a lack of oil supply, as Lee suggested.

However, at this point, that's just speculation.

jb

[detours]

I'm glad they found the issue and covered the repair under warranty. Hope you get it back soon!

[SpudRider]

Originally Posted by detours

I'm glad they found the issue and covered the repair under warranty. Hope you get it back soon!

X2 on all points.

[jbfla]

Metal tapping noise, part 2

My RX3 has returned from its 3 week California vacation.

What could be better than uncrating your RX3 twice?.......maybe not having to uncrate it twice.

The cardboard and reinforced pallet were in perfect condition:





The verdict is in and.......

I'm guilty, ..........

and no, it's not covered by the warranty......

What caused the metal tapping noise?

“The problem was:

Exhaust valve had no or too little valve lash

Scored / stressed the exhaust lobe base circle

which also operates the compression release mechanism which made the noise.”


The parts that were replaced:

Camshaft with bearings
Roller rockers
Cam chain
All gaskets for top end

Repair costs would be in the neighborhood of $500, parts and 4 hours labor.

My shipping cost was $635. from Florida to California.

Return shipping was around $500, plus there is usually a $150 crating charge.


This could have been a financial disaster...



But remember the part where CSC told me (by phone call) that I would be 100% satisfied.....



The full repair bill and the return shipping and crating charge were all covered by CSC's Goodwill Policy. As approved by CEO Steve Seidner.



Needless to say, I am extremely grateful for this decision.

All you CSC cheerleaders can stand up and do your happy dance....as will I.

Am I 100% satisfied?

Would you settle for 99.5%?

If not, I'll give them the 100%.

I would have liked to see the damaged camshaft or a photo of it.

I was told the camshaft would be returned to me with the bike...but perhaps that's nitpickin'.



There are still some lingering questions concerning exactly what happened, and if this is an isolated occurrence or not.

I know the simple answer....too little valve clearance on the exhaust valves caused damage to the cam lobe.

Head mechanic Gerry Edwards explained it to me on the phone and in an email but I'm still not sure how the decompression mechanism was involved.






About the valve clearances:

They were set to .003 inch during the setup by CSC.

At 850 miles I checked the valve clearances, and both intake and exhaust were still at the .003”

At 3,500 miles (2,650 miles later) the clearances were:

Intake increased to .005”

Exhaust decreased to .001”

The valve check was done on a totally cold engine.

Somewhere between 850 miles and 3,500 miles that .001" on a cold engine became zero clearance on a hot engine.



Consider this from Joe Berk's book, 5,000 miles at 8,000 RPM:

“...we made the decision not to do any valve adjustments during the ride unless the motorcycles started exhibiting symptoms consistent with the valves being too tight.

Valve gaps always tighten when valves and valve seats wear.

The symptoms can include hard starting, low power, or the engine stops running and starts making clanging sounds when things break inside.

…when we returned to Azusa, and based on our findings we subsequently increased the valve gap inspection and adjustment interval to 5,000 miles...”


In my case there were no warning signs.

The engine started with the first push of the starter button.

The engine had good power.

And by the time I could hear any “clanging sounds”, the damage had already been done.


On my TW 200, I had a valve adjustment lock nut loosen, and come completely off.

There was the hard starting, and extreme loss of power, but I was able to ride the short distance home.

When I removed the top end of the engine, there was no damage to any parts.





I'm still pondering these questions:

How much did the decompression mechanism contribute to the damage?

Does a 250 cc, electric start engine, even need a decompression mechanism?



The prescription by head mechanic Gerry Edwards was to:

Check / adjust valves at 500 miles.

Check adjust valves again at 2500 miles and every 2500 thereafter or sooner if start / idle problems.

Use 20w50 motor oil.


At this point, I am a happy RX3 owner.

It was an expensive lesson for me and for CSC.

I had to pay the $635. for shipping (IMO, still the right thing to do).

Since this repair was not considered a warranty issue, I do not believe CSC will be reimbursed by Zongshen.

But for the Goodwill of Steve Seidner and the folks at CSC, it could have turned out much worse.

And..............like it or not,....

....check your valve clearances.

jb

[Eco Mouse]

So let that be a lesson to all you out there who is considering buying a bike, sight unseen on the internet... you are responsible for your valve clearances! And if you don't know what that is, then you should by another bike.

It's awesome that CSC did their best to make you happy and get your bike back to you. Now get out there and ride!

Actually, your tale woe, has me pondering my clearances, and perhaps, I'll get into the shop this weekend, and do that!

[BlackBike]

Wow,