Rocker Face Pitting

[umrll]

I'm building a R100/7 from a stripped bottom end and recently purchased these rockers with refinished faces, however one of them has a relatively deep pit. A few of them need new needle bearings as-well despite being told they were all fine. I've attached pics below. The engine is completely stripped and getting all new bearings, seals, sprockets, conrod bearings etc so i'm hesitant to use the rocker as is but it's possible I'm over reacting. What are your thoughts? Edit: Both pics are of the same rocker arm tip

 

[20774]

Welcome to the forum! I would think that the imperfection could present a problem with where it contacts the valve stem. I'm not sure how much or what part of the rocker arm actually makes contact...could be that the pit is off to the side. One thing that I wonder about is how the surface of the rocker arm is treated. Some parts of the valve train have a special surface treatment that might be fairly thick like maybe 1mm. This treatment can't be ground down as it will defeat the purpose of the surface treatment. This might be more for something like the cam follower faces, but I just wonder about the rocker arm faces.

Hopefully someone like Anton will drop into the thread and offer his opinion.

 

[umrll]

Thanks for the welcome! Yes my main concern is it'll eat the valve face and i'll end up with metal where i don't want it. You can see by the discoloring on the tip they're heat treated

 

[barryg]

It’s bothering U. Ur there, change it out; install new or good used no pitted rockers. Peace of mind is what it’s all about.

 

[umrll]

It’s bothering U. Ur there, change it out; install new or good used no pitted rockers. Peace of mind is what it’s all about.

I hear you, its that i just bought these as refinished for $200 so i'd rather ask the gurus first before spending even more

 

[20774]

Can you complain to the people that refinished them?

 

[umrll]

Can you complain to the people that refinished them?

I can complain but likely they wont do anything. EDIT: Contacted the shop and he said he'll try reworking it.

 

[stevenrankin]

Wait a bit

If it were my situation, I would wait a bit before installing and contact someone like Anton or Tom Cutter, Ted Porter. Perhaps even Snowbum's site will have a document as to how these are finished and what if any thing could cause them to become NG.

The guy who "finished" them the first time, may not have done the correct thing and "refinishing" them may lead to even bigger problems, why take the chance. I may be nasty but if someone gave me those parts in that condition as "finished" or "resurfaced" I would doubt them.

First of all, what did they look like be before finishing? You don't know, and that worries me, how much surface had to be removed to get them too look like this? No, I don't know of any specifications or tolerances off the top of my head, to tell you for sure they are Okay to use or not.

In the long run new ones at Max are pricy. Unfortunately, used ones unless bought from a trusted used parts house are suspect. Not all deals on used parts are good deals.

I think I would Bite My Wallet and buy new ones. I only say that because if I took the time to put a bike together to ride, I don't want to be pulling it apart later for a failure of a part, I had doubts about. The bikes were not meant to be worked on but to be ridden. LOL, it is tough enough keeping a bike running well when you have had it from new but it can drive you crazy to restore an unknown bike and find yourself working on it far more than you want spending more than budgeted or expected. I have been in both places with my two airheads.

Good luck with what ever you do and I do hope someone else comes online with data. St.

 

[robsryder]

Given the need for a hardened, smooth surface in this application I think that I would opt for new rockers if it were me. It is a bitter pill to have spent almost half the cost of new items, but the potential for damage to engine parts and having the piece of mine would push me to new.

From the MaxBMW fiche for a 77 R100RS (which would be my interest, should the need arise). Items #5 and #6 from the exploded diagram. Need 2 ea of NR1 (...713) and 2 ea NR2 (...715) -

 

[stevenrankin]

Valves

Yeah, $500 and some change is a bit but worth it in the long run.

There are some good reputable used parts places out there such as https://re-psycle.com. or I have dealt with https://www.motorworks.co.uk/vlive/Home/index.php. My favorite guy has retired from the used parts business or I would list him. Either of these two companies and (perhaps someone else in the forum has a list for reputable used parts), sure beat some of the mystery stuff sold by a lot of the Ebay people. That said, if you purchased through Ebay, have you looked into a refund? A refund would ease the cost of new parts.

Good luck, St.

 

[umrll]

Yeah, $500 and some change is a bit but worth it in the long run.

There are some good reputable used parts places out there such as https://re-psycle.com. or I have dealt with https://www.motorworks.co.uk/vlive/Home/index.php. My favorite guy has retired from the used parts business or I would list him. Either of these two companies and (perhaps someone else in the forum has a list for reputable used parts), sure beat some of the mystery stuff sold by a lot of the Ebay people. That said, if you purchased through Ebay, have you looked into a refund? A refund would ease the cost of new parts.

Good luck, St.

Tom Cutter replied in the airhead group last night that he "would't run them or resurface them", after that I picked up a set of rockers on ebay. They looked pretty decent and for $60 it's worth a shot over $500 new. We'll see

 

[stevenrankin]

thanks

Thanks for the update. Just out of curiosity did Tom give you any kind of way to check what condition the parts should be in? Did he give any specs or clues to look for to determine parts are good?

I do occasionally buy from Ebay but rarely and ONLY if I am 100% certain of what I am getting. I won't throw rocks at the honest guys selling used parts there but, like any used parts business, there are good guys and bad guys. One of the good things about Ebay is their policy for dispute. Luckily I have never had to use it but it is better than buying parts from a private individual.

Sadly, I do see a lot of high priced junk being sold on Ebay at times. Sorry, not to be a pain, just adding to the topic. I hope things work out well for you. St.

 

[umrll]

Thanks for the update. Just out of curiosity did Tom give you any kind of way to check what condition the parts should be in? Did he give any specs or clues to look for to determine parts are good?

I do occasionally buy from Ebay but rarely and ONLY if I am 100% certain of what I am getting. I won't throw rocks at the honest guys selling used parts there but, like any used parts business, there are good guys and bad guys. One of the good things about Ebay is their policy for dispute. Luckily I have never had to use it but it is better than buying parts from a private individual.

Sadly, I do see a lot of high priced junk being sold on Ebay at times. Sorry, not to be a pain, just adding to the topic. I hope things work out well for you. St.

His response was verbatim "I wouldn’t run those or whetstone them.", i didn't press further. It's possible the new incoming rockers can be junk but a $60 used set vs $500 new its worth taking a chance, and atleast i'll be able to return them if thats the case

 

[Omega Man]

It wouldn’t have occurred to me that it was possible to “refurbish” that part. Seems like a a good or bad item to me. I’m thinking that a new part has a particular surface hardening and finish.
It will be interesting to see how this works out.
OM

 

[brook.reams]

It wouldn’t have occurred to me that it was possible to “refurbish” that part. Seems like a a good or bad item to me. I’m thinking that a new part has a particular surface hardening and finish.
It will be interesting to see how this works out.
OM

I believe the tip is heat treated to harden it. So, any grinding to "refurbish" it will remove the hardened layer requiring heat treating again to harden the new exposed layer. Anyone doing that better know what they are doing.

Best.
Brook Reams.