How Do You Degree In Cams

[Der2z]

Ok I talked to WEB CAM and they gave me some information on a set of webs that would work good for my bike, but I have to degree them in. I bought adjustable cam sprockets but I dont have a clue on how to degree them in beside finding top dead center and using a degree wheel

[CFM-Z440]

Derek, PM me your number and I can try to explain it... Its a very long process and it is dificult to put down in text... This may help though...

First you need to find your true Top Dead Center on the compression stroke...

Finding TDC

You mount the degree wheel to the crank shaft and line up 0 some where near where it should be. Then you make a pointer out of a stiff piece of wire.

Then you take the spark plug out, move the piston away from top dead center and install a positive stop (which is kind of hard to find in the 10mm size that fits the Z)


Then you rotate the engine carefully untill you come up against the positive stop with the piston, note the degree reading, then rotate the other direction untill you come up against the stop again, note the reading.

Adjust the pointer untill you hit the same number of degrees from 0 each way.

Then after all of that, 0 on your degree wheel is exactly at top dead center






I copied this from Tony Tice somewhere and it describes it better than anything else I have read...


Finding Lobe center line angle Quoted from Ticeman (the guy who designed hot cams)


Lobe centerline is the relationship of the camshaft to the crankshaft at any given crank angle when the valve is off the seat using equal opening and closing lifts of the valve. The lobe centerline can then be figured in degrees of crankshaft rotation by finding out how far the crank has been rotated and how long the valve has been open during that time.

Since we already know that the duration of these cams are 243 deg we can figure out what the opening and closing should be with the valve lash set at ZERO. We could work this backwards but it won't give you the corrct perspective of what's actually happening. We know that the intakes are going to open before bottom dead center and close after top dead center. Using a degree wheel on the crankshaft and finding ABSOLUTE TDC with a positive stop so that we KNOW where TDC is actually at, you rotate the crank clockwise until the valve is lifted off the seat .050" measured with a dial gauge that is set-up to the correct valve actuation angle. If the lash is zero it will lift at 49.5 deg BBDC and it will be at 13.5 deg ATDC when it closes. I'll short cut the math for you using a 90 deg wheel. 49.5 - 13.5 = 36. 36/2 = 18. 18 + 90 = 108

These cams are symetrical and means that the exhaust is figured the same way as the intake. It'll open the exhaust valve at 13.5 deg BTDC and close at 49.5 deg ABDC. Same math applies.

You have to keep in mind that it's VERY important to make sure all your readings are consistent. Do this a couple three times to make sure it reads the same each time. If it doesn't, something is set-up wrong.

[NormalZ]

Here's a step-by-step of all the steps you need to take to degree cams, but you'll have to research how to do each step on your own.

Tools needed:

• All the common tools to take down/rebuilt the topend on your motor...
• Degree wheel, with pointer
• Positive stop
• Dial Indicator with stand, either magnetic (less desirable) or a screw in base that you can mount to the cylinder head (more desirable).

The process, in steps:

• Step 1 - Remove left side cover from the engine.
• Step 2 - Set your motor at TDCC.
• Step 3 - Mount the Degree Wheel and pointer, pretty close to TDCC.
• Step 4 - Remove sparkplug, install Positive Stop.
• Step 5 - SLOWLY rotate the motor over by hand until the piston lightly contacts the Positive Stop.
• Step 6 - Annotate the degrees of Crankshaft rotation at this contact position.
• Step 7 - SLOWLY rotate the motor over by hand in the other direction, until the piston lightly contacts the Positive Stop.
• Step 8 - Annotate the degrees of Crankshaft rotation at this contact position.
• Step 9 - Do the math on the degrees of contact (BTDC and ATDC, and set True TDC on the Degree Wheel - "zero" the Degree Wheel (That whole process above is just to find True TDC).
• Step 10 - Remove the Positive Stop.
• Step 11 - Verify that "Zero Degrees" on the Degree Wheel is actually where the "TDC marks" in the flywheel and engine case line up, and that the piston is actually at TDC.
• Step 12 - Rotate the motor over by hand and determine where the Intake cam opens and closes (usually at 0.040" of lift is where you measure "opening" and "closing" on most motorcycle engines). Annotate the results.
• Step 13 - Rotate the motor over by hand and determine where the Exhaust cam opens and closes.
• Step 14 - Annotate the results.
• Step 15 - Determine the Lobe Centers of the cams you have based upon the numbers.
• Step 16 - Set the cam you want to adjust to it's Lobe Center (so valve spring pressure holds it open, at max lift).
• Step 17 - Loosen it's adjustable sprocket bolts.
• Step 18 - Rotate the motor over by hand until you've adjusted the Degree Wheel "xx" degrees - your new Lobe Center.
• Step 19 - Tighten the adjustable sprocket bolts.
• Step 20 - Rotate the motor over by hand to verify the new Lobe Center, and that the opening and closing degrees shifted the amount of degrees you were trying to change (either advance or retard). Sometimes this process takes two or three times to get it right, until you get the hang of the motor you're working on - very seldom will you nail it the first time you work on a motor you haven't timed cams on before.
• Step 21 - Repeat this process for the other camshaft.
• Step 22 - Put the motor back together...

[quadlt250]

this should be pinned

[sprinterx]

Nice work, I hope you had those "cut & pasted" from some where. They should be pinned.

[NormalZ]

QUOTE (SprinterX @ Apr 8 2008, 06:32 AM)

Nice work, I hope you had those "cut & pasted" from some where. They should be pinned.[/b]

No, brother - in my mellon! The only place I've written that so far is right up there ^^^. I did copy Chuck's stuff, though!

[advantagecycle]

The only suggestion I would have is to make sure that when you are refrenceing the lobe centers, you also note the lift at which "open", and "closing" are. Normal Z is right, most times its 0.040", but I've seen a few 0.020", and 0.060" too.

Paul

[NormalZ]

Good point, Paul! I think Hotcams lists their tech numbers at 0.050", too (duration and lift). Depends on the manufacturer (Web, MegaCycle, Hotcams), if you're trying to compare data. I have no idea what lift those others list their data at.

[N.J.C.]

QUOTE (NormalZ @ Apr 19 2008, 01:07 AM)

Good point, Paul! I think Hotcams lists their tech numbers at 0.050", too (duration and lift). Depends on the manufacturer (Web, MegaCycle, Hotcams), if you're trying to compare data. I have no idea what lift those others list their data at.[/b]

I'm thinking Web measures them at 0.039". They say MM on their site but I thought it converted to 39 thousandths.

[NormalZ]

QUOTE (N.J.C. @ Apr 19 2008, 01:33 PM)

I'm thinking Web measures them at 0.039". They say MM on their site but I thought it converted to 39 thousandths.[/b]

The Webs are listed at 0.050" - from their LTZ webpage:

Suzuki LTZ 400 (02-07) DOHC 4v - DURATION @ 0.050"

[ltz470 monster]

what does this do to your quad. degree ing your cams?

[matt133229]

I am about to degree mine in in a few days and have been researching the process, thought this was a very good read on lobe centers and thought it might be worthy of posting here for reference: http://www.muzzys.com/articles/lobe_centers.html

[kmkcummins]

like said, what does this do and when is it needed? With hotcams i thought you just put them in and adjust the valve bucket shims...im about to buy a set of used hotcams, am i going to have to degree them in?

[cataway]

from the factory i would say no. from a +5 stroked motor yes as its been said send them to hot cams and they will do it for you for just the shipping both ways . my self i have never done that so you do want to call them to confirm whats been said about the price

[spize909]

Originally Posted by kmkcummins

like said, what does this do and when is it needed? With hotcams i thought you just put them in and adjust the valve bucket shims...im about to buy a set of used hotcams, am i going to have to degree them in?

I bought a set of used Hot Cams and when I got them it was obvious by just looking at them sitting on a table that they were off by a long shot.
The good news is that if you send them to Hot Cams they will do it for you for free