Just another 2056 build, Misc Questions Options

[stugray]

I checked each one so I could measure for each rod and cut them to exact length individually.

I measured them all and found the average and cut them all to that length.
I didnt want to have to keep rods with certain valves.

And regarding the rocker ratio: If you know the cam lobe lift and now measure the valve lift, you can calculate the ratio.
If you felt like measuring it now, measure how much vertical motion you have on the pushrod with a second dial indicator while measuring the valve lift:

(IMG:http://www.914world.com/bbs2/uploads_offsite/i366.photobucket.com-10819-1355972519.3.jpg)

I used a tiny clamp on the pushrod

When I did this the first time I was given the lift at the cam and had to determine that the valve lift was within the 5% of predicted, but then you need to know the rocker ratio to at least two decimal places....

[sdoolin]

So while I am waiting on my 12" Vernier Calipers to arrive (so's I can accurately measure for pushrod length) I decided to go all creative on the oil fill tube block off plate with some custom engraving...



This engine is officially "one of one".

[sdoolin]

I've gone over the top again. I didn't like the way the swivel foot adjusters were lining up on the valve stems. First pic shows how the #1 intake swivel foot is not even covering the entire valve stem...



Pretty much all of the valves were like this, with the intakes being farther "off" than the exhausts. Back to the lathe to make each of the rocker shaft clamps slightly oval allowing them to move the rocker(s) over on the shaft...



Each clamp was cut in the neighborhood of .5mm, one set was cut .75mm. This got the swivel foot adjusters nicely aligned with the valve stems (picture in next post). Note they are still slightly off center which may allow for the swivel foot to spin the valve, but I'm not sure that spinning the valve even happens with the swivel foot adjusters?

[sdoolin]

After the clamps were "ovaled"...

[Montreal914]

Isn't that mis alignment there so that the valve is actually rotated over time as it is being opened? (IMG:style_emoticons/default/confused24.gif)

[sdoolin]

Isn't that mis alignment there so that the valve is actually rotated over time as it is being opened? (IMG:style_emoticons/default/confused24.gif)

Yes I believe that is the reason for the "mis-alignment", and why I left them somewhat mis-aligned. Though I don't see how the swivel foot adjuster is going to be successful rotating the valve. Maybe it does, I just don't know...

[jcd914]

Isn't that mis alignment there so that the valve is actually rotated over time as it is being opened? (IMG:style_emoticons/default/confused24.gif)

Yes I believe that is the reason for the "mis-alignment", and why I left them somewhat mis-aligned. Though I don't see how the swivel foot adjuster is going to be successful rotating the valve. Maybe it does, I just don't know...

Yes the off set of the rocker is by design not a manufacturing error.

The rocker pushing off center causes the valve to rotate slightly each time it is opened, this helps keep the valve and valve seat clean.

Jim

[sdoolin]

Life has gotten in the way of this project for a few weeks, traveling for work and all. I believe I have finally arrived at a happy place with respect to pushrod length.

Cyl IN Lift EX Lift
1 0.449 0.427
2 0.451 0.426
3 0.452 0.416
4 0.450 0.423

Note 1: All with thickest rocker shaft spacer
Note 2: All with 10.754" pushrod

All of those lift numbers are within the +- 5% range suggested by Raby. Also all adjusters nicely aligned with the valve stem at half of measured lift. I still plan to measure valve - piston clearance before final assembly.

It does seem like the swivel foot adjusters may contact the valve covers, I still need to measure that.

[sdoolin]

Clayed the heads this weekend to ensure no piston/cylinder contact. Looks like I will be fine. Measures right around 2mm...

[Dave_Darling]

How about with the valves opening? Or am I jumping ahead too far?

--DD

[sdoolin]

How about with the valves opening? Or am I jumping ahead too far?

--DD

That _is_ with the valves opening. You can see indentations from the valves in each of the clay strips. Why would one clay the heads except with valves operating?

[stugray]

Did you measure cam lobe lift before you installed the cam?
Just curious.

And the valve clearance seems a little close @ 2mm.
That is ~.080.
I seem to recall someone telling me they liked no less than .120, but I would have to check my notes, so don't quote me yet.

And my final length on pushrods was 269.5mm (10.61 in.)

[draganc]

sorry for the OT request: can you post a pic of your Ducati frontend setup. i'm curious what you did to the caliper mount(s). I tried to zoom into the pics but it's either covered or blurry.

[barefoot]

Did you measure cam lobe lift before you installed the cam?
Just curious.

And the valve clearance seems a little close @ 2mm.
That is ~.080.
I seem to recall someone telling me they liked no less than .120, but I would have to check my notes, so don't quote me yet.

And my final length on pushrods was 269.5mm (10.61 in.)

Just got my WebCam #494 and measured lobe lift at .345".
WEB card says valve lift is .465" so they assume a rocker ratio of 1.347

[HAM Inc]

In most of my experiences degreeing T4 cams and setting geometry the intake ratio came in around 1.33 and the exhaust around 1.29.

For years most cam manufacturer used a factor of 1.3 for intake and exhaust.

When we prep heads we set valve spring coil bind limits for any given cam based on my findings.

[stugray]

In most of my experiences degreeing T4 cams and setting geometry the intake ratio came in around 1.33 and the exhaust around 1.29.

For years most cam manufacturer used a factor of 1.3 for intake and exhaust.

When we prep heads we set valve spring coil bind limits for any given cam based on my findings.

Thank you!

You might recall my thread about rocker ratios.
I got my ass chewed by people telling me "Just use 1.3 like everyone else!" (IMG:style_emoticons/default/shades.gif)

They must not understand that to get within the 5% valve lift that Jake advertises that you MUST achieve (that is 0.05) you need more than TWO significant figures!

So there is a big difference between 1.29 & 1.33 when trying to calculate valve lift to THREE significant figures.

And my webcam 86b has an advertised valve lift of 0.500/0.500
I measured the cam lobe lift before installation and got 0.365/0.365
So for them to make a cam with 0.365 lobe lift and advertise 0.500 valve lift (.500/.365 = 1.37) they used 1.37 for their rocker ratio.

I installed the cam and measured .504/.475 so the rocker ratio in my engine is closer to 1.38 I/1.30 E.

[sdoolin]

sorry for the OT request: can you post a pic of your Ducati frontend setup. i'm curious what you did to the caliper mount(s). I tried to zoom into the pics but it's either covered or blurry.

Happy to post Duc pics. I made the Brembo mounts such that I could go back to the APs if ever needed, keeps value in the bike. The forks were not modified at all. I think they are kinda fugly, but they sure do work. Note that the pads don't sweep the entire rotor so there is some rust that develops on the inside "ring" of the rotor. Scotchbrite was invented to fix that. Pic...

[sdoolin]

Powder coating finally done. I think it all turned out pretty nicely. Still gonna be awhile till it runs. I still need a dizzy, going to ceramic coat the header/muffler (Bursch), and the dual Dells need to have the CB update kits installed along with complete rebuild.

[RoadGlue]

Dear God, that's one awesome bike!

(IMG:style_emoticons/default/pray.gif)

[sdoolin]

More PC pics...