Broken rocker arm

[uberranger]

So I posted a while ago that I thought I bent a valve when I ran the bike with messed up timing.  Well, I didn't; I instead broke a rocker arm. 

I need some opinions:
     -actually try to replace all the broken pieces (at least one rocker arm)
     -buy a used head
     -?

help!!!

If replacing the entire head is the choice option, where might I get one?  I don't see many on ebay...

[uberranger]

Also, which cylinder heads cross-fit? 

I believe the 800SS will (being the SAME engine)

What about others?

[motoxmann]

do you have the head off?
are you absolutely sure none of the valves got bent?

if the valves and valve seats are ok, I'd just replace the broken bits

[uberranger]

I got the head partially off and took the head covers off to get a good look.  The valves and guides look okay, though I'll likely check them again soon after it stops raining. 

So I guess no, I'm not entirely sure the valves aren't bent... 
The cylinder doesn't have any obvious imperfections either, so I may be okay there.


If anybody has any leads on a horizontal cylinder head...


SOOOOOOOOOOOO FRUSTRATINGGGG GYAAAHHHH


Sorry...

[chris1044]

If this were my bike, I'd pull the head and do a full disassembly.  It's the only way to be sure nothing is bent. 

Valves need to come out, be put into v-blocks with a dial indicator on the end of the stem or something similar.  If the force was enough to break a rocker arm, I'd guess it was enough to tweak a valve.  A little bend will do a lot of damage to the guide over a few hundred miles...

That said, before I pulled the heads I'd do a cylinder leakage test on both cylinders.  This will help you ensure the pistons aren't cracked if the valves did infact hit them - otherwise the magnaflux type crack-finding is in order for the pistons.

[uberranger]

Does anyone know what heads are compatible with the S2R 800?  I am pretty sure the SS 800 heads work, and am looking for everything else that might.  I think the 620 heads bolt up, but have smaller valves or something.  Any info is greatly appreciated. 

[Howie]

A cylinder leakage test will tell you all you need to know.

[lazylightnin717]

If it were me, I'd replace the head with a used one

Check the valves first, slap it on and ride

I picked up a pair of 748 heads for $300... not bad

[He Man]

i feel your pain. I cant know for sure, but i suspect at least 1 or 2 bent valves from my recent debacle. Buying a head is nice and dandy, but you can get all 4 valves repalced with kibble whties and guides for around $600 bucks and get a better running engine.

[Speeddog]

IME, if you've broken a rocker arm due to valve/piston conflict, your chance of no bent valves is zero.

A bent valve usually cracks the guide.

Pull that head off to assess the damage in the head, and also what condition the piston is in.

695 and 800 have the same valves and cams.
Not 100% sure the heads are identical, but I suspect so.

[Cloner]

Also, 800s are one of the engines built with both 8mm and, later, 7mm valve guides.  What year is your 800?  Make sure you buy the right stuff!

[uberranger]

It's a 2006 S2R 800. 

Are the KW valves good? I looked at them but have read mixed reviews.  If they're adequate, I may just redo the valvetrain and jump on it.  I can get the rocker arm(s) for ~125/pop.

Darn...just when I was beginning to think an S4 engine was the only viable option...XD

[He Man]

They are better than stock, but there are better options. Theres a shop if i can find their name, that makes custom guides matched to valves so you get the best fitting possible, and if u just cut the seat good you should get a great seal and itll be better than stock for sure.

[uberranger]

Found a full set of rocker arms (8 pcs) on ebay for ~$150, so I was all over that.  I'm going with KW valves in the next few days unless someone has a suggestion otherwise!

I don't know for sure if any but the one rocker arm I saw is bent, but I figure having a whole set for about the price of one won't hurt anything.

I may also just buy both valves/guides because I got this set so darn cheap.

So, any FHE with KibbleWhite valves/guides?

And for those who know:  If I get used rockers, new valves/guides, can I just lap the valves in, set the clearances/etc and call it good?  Is that about how it goes?  Or is there some other voodoo involved?

[Speeddog]

If you get new guides put in, the seats must be re-cut to match the new guide position.