Rocker arm differences

[TiZiK]

Hey all! Happy new year and all that. 
 

Swapped out the cams and rockers on the gsxr 1100g from the spares I had tucked away. Was in the process of setting valve lash (0.005”) and while turning the engine over, intake valves touched the piston. 
Double checked the clearance and was spot on. Increased to (0.006”) and valves still touching. 
Measured cam lobes and base circle and on all 4 sets I have here, they measured the same.  28mm base circle and roughly 34mm height. 
Now I’m scratching my head like wtf???

Checked the rockers and the screw adjusters. All the screw adjusters are the same. I did notice a difference in shape tho as outlined in the attached pics. 
 

One style is relatively flat between the two adjusters. 
The other style has a different casting shape. 
I never noticed this before. Upon noticing, there are 2 cylinders which have the different casting shape and with valve lash adjusted to spec, they don’t touch the piston even though the cam lobes are the same measurements. 
 

Can anyone shed some light on this? What am I missing?

Do the different style rockers have a different angle which opens the valve more even with the correct clearance?

Engine was running fine with no clearance issues. Had an oil pressure issue which took out the old cams. 
 

Edit: I did strip a dot head and put cams and rockers in with my spares Didn’t notice the difference until now  

Edited January 10, 2022 by TiZiK

[Upshotknothole]

They use the same part number for all of the tappet rockers in the oil cooled bikes from 86-06. Sure the cams are aligned correctly? Also if the rockers show any signs of wearing through the hard surface coating, they're garbage unless you get them resurfaced. Curious if that top one was already resurfaced at some point. Do you have enough matching rockers to put together a matching set? Verify the sprockets are the same as the old cams and that they're lined up the same?

 

I checked APE's website and they only mention repairing the rockers, no mention of them ever being any different ones for the tappet heads. Webcams only lists two different styles, standard and high lift. Guessing some of them were repaired in the past. Just try and match up 8 of them and double check the cam sprockets.

Edited January 10, 2022 by Upshotknothole
More info

[TiZiK]

Cams are lined up properly. I mean, they really only go in one way unless forced. Lol

I swapped the sprockets as they’re slotted. 
I picked the best of the bunch from the spares I had. A couple are on the iffy side. I’m wanting to confirm my oiling issue is resolved and I am planning to send out a set for hard welding. Bloody expensive tho. 70$ usd each rocker from A.P.E. 
 

Just baffled as to why the valves are touching now. 
 

I’ll give it a day to see if anyone has come across this then I’ll swap the rockers for the flatter looking style. 

[TiZiK]

Wait a sec. If you mean lines up properly as in timed correctly then yes. Intake was set 22 pins from the exhaust. At TDC, cam positions look correct. 
Maybe I’ll pull out the degree wheel tomorrow and verify. 
 

[Upshotknothole]

2 minutes ago, TiZiK said:

Wait a sec. If you mean lines up properly as in timed correctly then yes. Intake was set 22 pins from the exhaust. At TDC, cam positions look correct. 
Maybe I’ll pull out the degree wheel tomorrow and verify. 
 

Yeah, thinking the cam sprockets aren't lined up properly with the slotting and need to be checked. Even with the tappets backed all the way out, are you still getting interference when turning the engine over by hand? I've accidentally put the cams in 180 degrees off before and the engine still turned over fine, was just sucking instead of blowing at the exhaust.

[TiZiK]

Yes. With tappets fully backed off, no issues. Also, no issues on the exhaust side even with lash set to .005” 
I just went and had a look and the sprockets seem to be in the same spot. At tdc, the lines look correct and the lines on the right side end of the cams are lined up as well. 
I threw in the towel for the night so I’ll get at it again tomorrow. I’ve swapped cams so many times with no issues. It’s possible I over looked something. 
 

So even though the rockers look different, the dimensions should be the same?
 

[Upshotknothole]

I’ve never mixed up rockers before so I have no idea. If you’ve been working on it all evening the best thing to do is probably leave it for the night. Try matching up 4 rockers that are in similar shape and throw them on the intake side and see what happens. Are you here in the states?

[TiZiK]

I’m in Canada. Just north of Toronto. And ya, I’m leaving it for the night. I’ll check it tomorrow after work. See what’s what. 

[TiZiK]

Sorted. Apparently the operator was the error. Bike is EFI and I’m using a 36-1 trigger wheel. I was using the missing tooth as TDC when it should have been 90* from that. Maybe the fumes from the propane heater in the garage got to my head. Lol. It’s -20c or so here right now. 
 

Anyhow, all sorted now. Degreed the cams tonight. Onwards and upwards…

Edited January 12, 2022 by TiZiK

[Upshotknothole]

Sounded like a timing issue. Glad you got it sorted. It’s a hell of a lot warmer here in the PNW, but I’m still avoiding my garage until it gets warmer.