Topic: Rocker Arm Hardened Surface Wear

[stikman]

How concerned should I be about areas wearing through the hardened mating surface of my rocker arms?

I'm installing a brand new cam, so it seems only reasonable to install new rockers as well.  But looking for confirmation if this is necessary or not.

Also, if I do need new rocker arms, where would you recommend getting them?

It looks like Webcam does a hardweld on your old rockers.  Anyone gone that route? 

Cheers for any help fellahs!

[Sam Green Racing]

http://forums.sohc4.net/index.php?topic=134702.msg1535056#msg1535056

[PeWe]

My local tuner told me to check if chrome is OK, no flakes on the surface against the cam.
I have bought 2 complete sets of CB750 valve train this year, eBay has some for sale. Cam towers, rocker arms with shafts. Last buy included a K7-78 cam with sprocket, low mile.

All rocker arms look good, better than my old, especially the shafts since my original have almost 100.000km's, 30.000-35.000 of them with hotter cam. Cheaper when living in US with less shipping and customs, VAT...

[stikman]

That's just a link to a thread I started about camshafts, Sam.  Doesn't have any info on rocker arms.  Wrong link maybe?

I'll take some shots of my rocker arm mating surfaces and post them up.

[Tintop]

Should always use new, or refaced (hard weld) rockers with a new cam.  You can get old rockers hard welded through - MikeR, CycleX, Web, and Megacycle.

[Jerry E.]

Hard welding the rockers is expensive. I tried the performance coatings that Cycle X have for rockers, piston skirts, etc. They claim it is a high performance, high pressure coating that ingrains into the metal surface. They also use it on their racing bikes, and claim no problems. You can send them your worn rockers, and they will send back coated parts,that have been inspected for excess wear before coating. Is also supposed to lower friction/heat in the motor. So they say-I haven't ran it yet.

[bwaller]

I've seen disastrous results using existing rockers on new hardweld cams, don't do it. It is expensive but I'll always use welded rocker pads. After several race seasons they still look like new. Some have used new rockers. I wouldn't even consider those coatings....tell him Tintop!

[Tintop]

I've seen disastrous results using existing rockers on new hardweld cams, don't do it. It is expensive but I'll always use welded rocker pads. After several race seasons they still look like new. Some have used new rockers. I wouldn't even consider those coatings....tell him Tintop!

I'm not a fan of the coatings, they didn't stand up in the sidecar motor.  I am trying a different coating on the pistons, but it's NASCAR level stuff, and not cheap.  No way I would just coat used rockers (especially ones showing wear), on a new cam. 

[Jerry E.]

Don't know for sure about hard welded cams. My Megacycle cam is a "billet" cam ( not welded up and reground). The coated rockers I used were smooth, with no wear marks/grooves on them. I figured smooth rockers, with the coated surface, would work well. You can't buy new rockers anymore, and rewelding them was too pricey. Will find out when I start it soon-ready to start after I finish a little more wiring.

[Tintop]

The rocker coating is at best a friction reducer.  Having used rockers hard welded is cheap insurance vs wrecking a new cam & the rockers.

Just saying.

[azuredesign]

The rocker coating is at best a friction reducer.  Having used rockers hard welded is cheap insurance vs wrecking a new cam & the rockers.

Just saying.

That, and making sure there's good lubrication while all that hard stuff is beating on each other. Please don't ask me how I know this!

[Retro Rocket]

Why, with all the amazing stuff being made for our bikes has no one looked into making roller rockers...?  is there a reason i'm not seeing..?

[Jerry E.]

Having hard welded rockers, and a hardwelded camshaft promotes excess wear, or so I was told. Hondaman told me that one of the two need to be a "softer" material, so that one will wear evenly. This is also how it's done in car engines, he said. Using a billet (non welded) cam, with hard rockers wears better, or so he said. Or, a hardened cam, with "softer" rockers. One or the other, not both. The rockers are already factory hardened, I just added a slicker wear surface to it. Even if it wears off, I still have the hard, smooth rocker surface hitting the cam surface. At least, thats my theory. With Hondaman's input, when I did this to my motor.

[bwaller]

Having hard welded rockers, and a hardwelded camshaft promotes excess wear,

Sorry Jerry, I don't buy it in the case of lubricated parts. 

[Tintop]

Having hard welded rockers, and a hardwelded camshaft promotes excess wear,

Sorry Jerry, I don't buy it in the case of lubricated parts. 

+1  If that was the case you would think the cam manufacturers would have that in big bold type.

[Big Jay]

Having hard welded rockers, and a hardwelded camshaft promotes excess wear, or so I was told. Hondaman told me that one of the two need to be a "softer" material, so that one will wear evenly. This is also how it's done in car engines, he said. Using a billet (non welded) cam, with hard rockers wears better, or so he said. Or, a hardened cam, with "softer" rockers. One or the other, not both. The rockers are already factory hardened, I just added a slicker wear surface to it. Even if it wears off, I still have the hard, smooth rocker surface hitting the cam surface. At least, thats my theory. With Hondaman's input, when I did this to my motor.

Not true. We have been doing it for years in the GS Suzukis

[POPS 911]

Use a ZINC BASE OIL !!!!!  Oil companies worn out many cam when they took the zinc out of their oils...... Got many studies about this OIL PROBLEM in UNDERHOOD MAGAZINE.  Joe Gibb  NASCAR OIL has a zinc product in their for sale oil....

[MCRider]

If you do a Google search on "cryogenic rocker arms" you'll retrieve lots of testimonials and actual in use product (often referred to as "black ice") and such, mostly car guys: http://www.hughesengines.com/TechArticles/2cryogenicallytreatedrockerarms.php

Maybe the motorcycle guys are behind on this? Anyway its tough to allot the time and money to test and compare. Testimonials can be exagerated and misleading. But, its what I had done to my rockers, and virtually every other part in the engine and many in the suspension, brakes, lower legs. Mostly because its cheap.  Some say its snake oil. Could be. My project will never get the miles or abuse to know. So I'll never be the guy to make a claim one way or the other. Maybe someone else?

When I was doing it I got lots of feedback here from sports car guys doing it to their transmissions, (I did my CB750 as well) obtaining life and slicker shifts.  My cryogenics company was doing it for a few of the drag race top fuel guys based out of Indy, claiming 3x life of a top fuel block.

2 plusses: cheap v hardwelding, and; doesn't add anything to the piece that can come off or wear out. Its permenent.  Total cost <$600

PS: Last I looked I think Ken at CycleX is offereing it as well. Maybe he'll get some real world test results.